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Food traceability and authenticity Helena Čížková, Michal Voldřich and Petr Pipek PREFACE This manuscript has been prepared as the provisional textbook for the students of the Subject: Food traceability and authenticity guaranteed by Department of Food Preservation and Meat Technology of ICT Prague. The text is the compilation of general information, the scientific articles, legislative requirements and the own publication and academic observation of the authors. It provides an assessment of relevant legislative, analytical techniques and methodologies of authentication and examples of particular food and beverage products adulteration and the ways how to detect them. The syllabus of the subject: 1 Introduction..................................................................................................................................3

1.I The issues.............................................................................................................................3 1.II History of adulteration ........................................................................................................4 1.III Melamine case......................................................................................................................5

2 EU and national legislative background, responsible bodies.......................................................5 2.I European food authenticity legislation ...............................................................................6 2.II Consumer organizations and associations of producer ........................................................7

3 Methodology for food authentication ..........................................................................................8 3.I Methods................................................................................................................................8 3.II Data evaluation ....................................................................................................................9

4 Traceability, food labeling, fraudulent imitations of products and false declarations of geographic origin ...............................................................................................................................12

4.I Terms .................................................................................................................................12 4.II Sudan I crisis......................................................................................................................13 4.III Geographical indications and traditional specialities.........................................................13 4.IV Tracing the geographical origin .........................................................................................14

5 Fruit juices..................................................................................................................................15 5.I An example of the fruit juices authenticity development in the Czech Republic..............15 5.II An example of the confirmation of Aroma Restoration into the Reconstituted Orange and Apple Juices ...................................................................................................................................17

6 Fruit and vegetable products .....................................................................................................18 6.I Fruit purees and jams .........................................................................................................18 6.II Ketchups and tomato products...........................................................................................19

7 Milk and dairy products .............................................................................................................21 7.I The cases of milk and dairy product authenticity issues...................................................21 7.II Reference method for the determination of milk fat purity ...............................................23

8 Fats and vegetable oils ...............................................................................................................24 8.I The cases of vegetable oil authenticity issues :..................................................................25 8.II Olive oil..............................................................................................................................26

9 Meat and meat products .............................................................................................................28 9.I Adulteration of meat ..........................................................................................................28 9.II Adulteration of meat products............................................................................................30

10 Tea and coffee........................................................................................................................32 10.I Tea and tea based products ................................................................................................32 10.II Methods of tea authenticity testing ....................................................................................32 10.III The content of tea in tea-based products........................................................................33 10.IV Coffee.............................................................................................................................34 10.V Methods of coffee authenticity testing...............................................................................35 10.VI Differentiation of coffee varieties according to their sterolic profile ............................36

11 Honey.....................................................................................................................................37

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10.I Methods of authenticity testing..........................................................................................38 10.II Identification of artificial enzyme addition........................................................................40

12 Eggs and egg products ...........................................................................................................41 12.I The quality of technological liquid egg yolks....................................................................41 12.II Egg based products (pasta, egg liquers, mayonnaises) ......................................................42

13 Another cases of food adulteration ........................................................................................44 13.I Adulteration Of Whisky – historical view .........................................................................44 13.II Spices and flavourings .......................................................................................................45 13.III Detection of addition of artificial aroma into wine........................................................47

14 Recent issues and projects, practical examples......................................................................49 14.I Recent issues and current projects .....................................................................................49 14.II Practical examples for the evaluation of food authenticity according to provided data ....50

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1 Introduction

1.I The issues Food authenticity can be defined as whether the food purchased by the consumer matches its description. Misdescription can occur in many forms, from the undeclared addition of water or other cheaper materials, or the wrong declaration of the amount of a particular ingredient in the product, to making false statements about the source of ingredients i.e. their geographic, plant or animal origin. The criteria that define the authenticity or genuineness of food products are numerous and vary from one commodity to another. However the objective in all types of food adulteration is to profit by: 1. substitution of an expensive constituent with a cheaper one ( e.g. species or variety) 2. lowering the content of valuable constituent, dilution 3. use of different (cheaper) technology than is declared, mismatch of conventional to organic product 4. mislabeling, incorrect or insufficient description 5. false declarations of geographic origin, year of production 6. fraudulent imitations of products The ability to trace and authenticate a food product should be of major concern for both the food industry and official bodies. As it can be seen from the Table 1 all kinds of foodstuffs can be subjected to the adulteration both the most expensive ones and the cheap but sold in the high quantities. The names under which foodstuffs are sold should be based on objective considerations of product definition upon to:

• Definition in the FAO/WHO Codex Alimentarius • The rules and regulation of member States • The composition or method of manufacture of product • Reference in any community acts, including tariff nomenclature used in implementing the

Common Customs Tariff1 Table 1: The ratio of different adulterated foodstuff mentioned in FSTA (1999-2009) and the examples of adulteration Foodstuff % Examples

vegetable oils and fats

31 detection of adulteration of olive oil with other cheaper oils (e.g. hazelnut oil) or replacement of grades of olive oil of different prices. T

milk and dairy products

24 confirmation of spices (using caw milk rather than buffalos’ to make mozzarella), detection of the addition of lipids, lactose or casein, check flavorings (e.g. fruit, vanilla)

fruit beverages and products

12 detection of addition of sugar, water, colourings, aromas or other undeclared additives, determination of fruit kind and content

meat and meat products, fish

9 confirmation of the animal species; confirmation of adding excessive water to meat without declared it and substituting of meat with cheaper product in ham, confirmation of the species and of origin (wild farmed fish);

wine 8 detection of chaptalisation, sugaring, dilution or addition of glycerol, checking the process used in sparkling products, conformity to the isotopic profile;

spices and aromas

7 checking whether a flavour is natural (vanilla, aniseed, bitter almond, cinnamon, linalool, etc.);

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honey 5 detection of sugar addition

coffee, tea 2 checking for natural or synthetic sources in tea, coffee or guarana-containing drinks; detection of adulterating highly valuated Arabica beans with cheaper Robusta

spirits 2 control of the botanical origin of the alcohol, detection of addition of water, sugars or flavours (according to current regulations and/or product specifications);

cereals 1 confirmation of variety in cereals, quantification of the amount of basmati rice present in the rice.

chocolate and confectionary

1 evaluation of cocoa solids and cocoa butter in products and it replacement by cheaper vegetable oils

1.II History of adulteration

Food commodities have always been vulnerable to fraudulent admixture or adulteration with cheaper inferior materials. Such practices are revealed within countries when food materials are transported from the countryside to the urban centres. In international trade, such practices were noted in the eighteenth century when the UK and other European nations were importing spices, oils, oilseeds, honey, tea, coffee and such other materials from their colonies. Adulteration included black pepper with gravel, leaves, twigs, paper dust, linseed meal, pea flour, sago, rice flour; cayenne pepper with vermillion (mercury sulphide), ochre (earthy mixture of metallic oxides and clay), turmeric; essential oil with oil of turpentine, other oils, alcohol; vinegar and lime juice with sulphuric acid; coffee with roasted grains, occasionally roasted carrots or scorched beans and peas,

baked horse liver. A similar situation existed in other countries as well. At times, the adulterants were toxic as in the cases of mercuric sulphide, ochre, sulphuric acid mentioned above or the presence of lead chromate in turmeric and dimethylamino azobenzene or butter yellow, a hepatocarcinogen, in butter2. Many people ingested these and other substances and died. The cartoon is a contemporary comment on this.

LITTLE GIRL: "If you please, Sir, Mother says, will you let her have a quarter of a pound of your best tea to kill the rats with, and a ounce of chocolate as would get rid of the black beetles?"3

Table 2: Common food adulterants in England in the middle of 19th century4 Product Adulterants for bulk, weight Adulterants for colour, taste , smell Pudding powders

Wheat, potato and rice flour Lead chromate, turmeric to enhance the yellow colour

Coffee Chicory, roasted wheat, rye and potato flour, roasted beans,

Burnt sugar (black jack) as a darkener

Tea Used tea leaves, dried leaves of other plants, starch, sand china clay, French chalk

Plumbago, gum, indigo, Prussian blue for black tea, turmeric, copper salts for green tea

Cocoa and chocolate

Arrowroot, wheat, Indian corn, sago, potato, tapioca flour, chicory

Venetian red, red ochre, iron compounds

Cayenne pepper

Ground rice, mustard seed husks, sawdust, salt

Red lead, vermilion, Venetian red, turmeric

Pickles Copper salts for greening

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Gin Water Cayenne, cassia, cinnamon, sugar, alum, salt of tartar

Porter & stout

Water Brown sugar, capsicum, ginger, wormwood, coriander and caraway seeds, liquorice, honey, cream of tartar,

1.III Melamine case Even now, the situation may not be any better in certain countries. The adulterators are quite innovative although unscrupulous. The case of melamine can be given as an example. Melamine is an organic base and a trimer of cyanamide, with a 1,3,5-triazine skeleton that contains 66% nitrogen by mass. It is broadly used for the production of countertops, dry erase boards, fabrics, glues, housewares and flame retardants. Due to the high concentration of nitrogen in molecule it can be used as an adulterant to increase the total amount of nitrogen in milk, dried milk and milk products as the determination of nitrogen (protein content) is one of the basic method for the evaluation of their quality. The scandal raised in Chine in the middle of 2008 involving milk and milk based infant formulas (and other milk containing foodstuff consequently), which had been adulterated with melamine, leading to kidney stones and other renal failure, especially among young children. Within 2008 nearly 300,000 people had become ill, with six infant deaths. Global impact of the case can be illustrated on the situation in EU, where 84 RASFF calls and 101 notifications dealing with the melamine in foodstuff were registered. Member States of the European Union are required under Commission Decision 2008/757/EC to ensure that all composite products containing at least 15 % of milk product, originating from China, are systematically tested before import into the Community and that all such products which are shown to contain melamine in excess of 2.5 mg/kg are immediately destroyed5.

2 EU and national legislative background, responsible bodies The wide prevalence of deceitful practices in the trade of food articles with respect to their quality firstly attracted the attention of the customs officess during the early eighteenth century when statutes were introduced for tea and coffee and which linked the tariff with the alcohol content of beer, wine and other alcoholic beverages with the sole objective of protecting the revenue. However, the possible health implications of the adulteration and indiscriminate use of chemicals as preservatives, colourants and improvers for food products prompted at the end of 19th century responsible bodies of European countries to set up new legislative rules for food and drink quality. In modern history , in 1962, the Codex Alimentarius Commission was established for implementation of the Joint FAO/WHO standards programme. The aims of Codex Alimentarius include protecting the health of the consumer, ensuring fair practices in the food trade, coordination of all food standards work, publishing regional and world standards, recommending international standards for individual foods and making provision with respect to food hygiene, contaminants, additives, labelling and so on. The Codex recommendations are often used by bodies like the European Union (EU) to formulate their standards. According to the pure food legislation in many countries, food is considered adulterated when the food article: consists of any filthy, putrid, decomposed or diseased animal or vegetable material; is insect infested or unfit for human consumption; is prepared, packed or stored under insanitary conditions; contains any poisonous ingredients; has been substituted by any inferior or cheaper substance; has had any constituent abstracted; is packed in a container of any poisonous or deleterious substance; has any unpermitted additive or has a permitted additive present

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in an amount exceeding the prescribed limit; consists of a quality falling below the prescribed standard; or is not as purported or claimed2. Food authenticity bases and responsible bodies: • national and EU legislation • official controls performed to ensure the verification of compliance with feed and food law • associations of producers • consumer organizations

2.I European food authenticity legislation EU Food low is based on the Regulation (EC) No 178/2002 of the European Parliament and of the Council of 28 January 2002 laying down the general principles and requirements of food law, establishing the European Food Safety Authority and laying down procedures in matters of food safety. In Article 8 it specifies the protection of consumers' interests: Food law shall aim at the protection of the interests of consumers and shall provide a basis for consumers to make informed choices in relation to the foods they consume. It shall aim at the prevention of: (a) fraudulent or deceptive practices; (b) the adulteration of food; and (c) any other practices which may mislead the consumer. Food law shall pursue one or more of the general objectives of a high level of protection of human life and health and the protection of consumers' interests, including fair practices in food trade, taking account of, where appropriate, the protection of animal health and welfare, plant health and the environment. The importance of commodity, the impact of producers associations and the existence of international standards is taken into the consideration in the case of regulation of particular foodstuff, when all of them are subjected to the general law requirements (e.g. labeling), some are restricted by directives relating to their quality and authenticity and some are more over specified by the methods for the analysis of quality evaluation (Table 3). Table 3: Examples of EU legislative relating food authenticity General Directive 2000/13/EC on the approximation of the laws of the Member States relating to

the labelling, presentation and advertising of foodstuffs Directive 90/496/EC on nutritional labelling for foodstuffs Products Directive 2001/112/EC relating to fruit juices and certain similar products intended for

human consumption Directive 2001/110 EC relating to honey Methods Commission Regulation (EC) No 273/2008 on methods for the analysis and quality

evaluation of milk and milk products Commission Regulation (EC) No 640/2008 on the characteristics of olive oil and olive-

residue oil and on the relevant methods of analysis EU legislation web pages and the examples of official web pages dealing with the food authenticity and traceability: http://eur-lex.europa.eu/ http://www.food.gov.uk/science/research/researchinfo/choiceandstandardsresearch/authenticityresearch/ http://ec.europa.eu/research/growth/gcc/projects/food-fraud.html http://ec.europa.eu/food/index_en.htm http://www.trace.eu.org

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2.II Consumer organizations and associations of producer Ensuring authentic food for all is a critical element of the consumer organizations agenda all over the Europe. Since their establishment, various consumer organizations have worked with its members to achieve this goal, campaigning on a wide range of food issues including:

• food quality • food adulteration • food labeling • biotechnology, irradiation and GMO

They have also run programmes on food quality and authenticity including research, training, capacity building, lobbying, campaigning and education. As an example of the role of producers associations the European juice and nectars producers associations can be taken. The quality and adulteration of fruit juices is a common problem in Europe, but during the years the volume of adulterated juices and nectars decreases due to the activities of the national fruit juice industries and their federation. Mislabeling and dilution of juices has been prevented in the EU, where the Association of the Industry of Juices and Nectars from Fruits and Vegetables of the EEC (AIJN) was established. The aims of the association are:

• Legal investigations and approaches • To assure free and fair competition. • To protect the image of the products and the industry. • To develop control systems in countries where these not yet exist and to harmonise existing

systems. • To harmonise and to create consensus regarding the interpretation of analysis results. • To create an early warning system for detection of falsification. • To establish a European data bank with authentic data on raw materials and consumer

products. One of the principle activities of the AIJN was the development of reference guidelines that were prepared on the basis of already existing information (RSK and AFNOR standards), such as national standards as well as literature and experience. The guidelines The Code of Practice of the AIJN, the first version was issued and approved by the European industry in 1990 and now consists of 19 reference guidelines: orange, grapefruit, apple, grape, pineapple, lemon, passion fruit, pear, apricot, tomato, black currant, sour cherry, raspberry, strawberry, peach, mango, guava, banana and mandarin. Each of the 19 reference guidelines of the Code of Practice contains general explanatory notes, basic (obligatory) quality requirements such as min. relative density and corresponding Brix values, isotopes, biogenic acids, ethanol, arsenic and heavy metals and the essential parameters and their characteristic value or range for the evaluation of identity and authenticity as well as some recommended quality criteria for juices, e.g. acids, minerals, sugars, amino acids, flavonoids, etc. Figure: Web pages of European fruit juice associations

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Relevant web pages: http://www.consumersinternational.org/ http://www.beuc.eu/ http://www.sgf.org/index.php?id=101&L=1

3 Methodology for food authentication Fraud is becoming more and more sophisticated and increasingly difficult to detect by basic analyses since it is often designed to get round the tests in use. It is therefore necessary to resort to advanced analytical techniques to detect the non-compliant products. Only a considerable investment in research and development enables laboratories to apply the most suitable methods to each specific case when evaluating the authenticity of a product6. Valuable research work must be carried out by laboratories to investigate the problem of dulteration, to lay down standard specifications and to devise analytical methods to detect and quantitate adulteration.

3.I Methods Conventional chemical approaches to food authentication have generally involved measuring the various constituents, physical or chemical parameters, of a particular product, or are based on single “ideal marker” of either the authenticity or adulterant presence. Determination of “fingerprints” of for example flavour compounds, oligosaccharides or near infrared spectrum by selected chromatographic and spectroscopic techniques have also shown considerable potential as rapid, non-destructive, screening methods. The relatively simple and time-efficient but valuable approach is organoleptic testing. Namely in the case of more expensive foodstuffs such as wine, spirits and olive oil, for which unbiased estimation if the product look, smell and taste as the standard product should and consumer would expect is crucial. Due to the fact that the considerable amount of data is usually generated the way of data collection, handling and interpretation is very important. Multivariate chemometric techniques and the reference base of non-adulterated, authentic samples are generally needed to extract the important information. Whereas for some food stuffs these data are generally available (Codex Alimentarius, USDA, AIJN Code of Practice) some sample groups requires deep scientific literature search or private databases to come over all potential variation within the geographical origin, variety of type of product, the year or type of production. Analytical tools to control product authenticity (Figure 1) are:

• large number of classic physical, chemical and biological methods: liquid or gas chromatography, spectroscopy (atomic absorption, ultraviolet)

• the use of isotopic techniques and in particular a method of reference in authentication -SNIF-NMR® ( Site Specific Natural Isotope Fractionation Studied by Nuclear Magnetic Resonance ).

• biochemical techniques and DNA profiling Figure 1: Analytical tools to control product authenticity

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Biology and biochemical methods• Electro-migration methods (proteins)• ELISA (Enzyme Linked Immunosorbent Assay) – soya, milk

proteins, allergens, meat species• Molecular biology methods - PCR (Polymerase Chain

Reaction), identification of DNA; GMO (“Roundup Ready”soybeans, “Maximizer” maize)

Classical methods • refractometry, titration, gravimetry• GC (sterols, TAGs, FA, terpens), HPLC (organic acids., flavonoids, sugars, AA), • Spectroscopy - UV/VIS (chlorophyll, proline), AAS (Ca, Mg, K, Na), NIR - fingerprints

Isotopes ratioIR-MS (Stable IsotopeRatio MS) 13C/ 13 C SNIF-NMR (Site-specific Natural Isotope Fractionation NMR), ratio D/H,

Methods

3.II Data evaluation • For databases the uncertainty is taken into account statistically • Variability is assessed via the authenticity calibration graph • Multi-analyte data –applied individually • Or combined e.g. as ratios, or through multivariate statistics

Figure: UNCERTAINTY OR DEGREE OF CONFIDENCE

The examples of standard composition data sources:

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• USDA National Nutrient Database for Standard Reference (http://www.nal.usda.gov/fnic/foodcomp/Data/SR15/sr15.html)7: The Nutrient Data Laboratory (NDL) has been compiling and developing food composition databases for over a century. Current version of the database is Standard Reference, Release 22. Find links to NDL resources, including online nutrient search, lists of individual nutrients, PDA downloads and more.

• Nutrition tables – e.g. Siegfried W. Souci • W. Fachmann • Heinrich Kraut: Food

Composition and Nutrition Tables, Stuttgart 2000, CRC Press8, The seventh edition builds on the strong base of the previous editions by incorporating discussions on select new foods, investigations in bioactive compounds, as well as additional and revised data on more than 800 foods and 300 constituents. Concentration of Food Constituents* Subdivided as follows: Main constituents (water, protein, fat, available carbohydrates and organic acids, total dietary fibers, and minerals), individual minerals and essential trace elements, vitamins, amino acids, fatty acids, individual carbohydrates (mono-, oligo-, and polysaccharides), hydroxycarboxylic acids (fruit acids and phenolic acids), sterines, biogenic amines, purines, phospholipides, and other consituents. The tables contain the nutrient amounts per 100 g edible portion (average and variation) and the nutrient density (nutrient content/energy value). For protein-rich food products, the amino acid composition is additionally given in mole percent.

• Juice standards - The A.I.J.N. Code of Practice for the Evaluation of Fruit and Vegetable

Juice (http://www.aijn.org/)9, is accepted and used by the National Fruit Juice Associations within the EU, by national food inspections as well as by fruit processors and traders all around the world. It is also acknowledged by the EU Commission. Furthermore the acceptance of the Code of Practice is a mandatory requirement for all participants in the European industrial self-control organisation (EQCS) and also for the members of the International Raw Material Assurance Organisation (SGF/IRMA).

The Code contains: 3 Preface including the general operation of the Code 3 Comments, general and detailed, on the reference guidelines 3 Individual reference guidelines for 20 different juice varieties, which include Brix, acids,

sugars, 3 flavonoids, mineral contents and isotopic parameters 3 Provisional Brix and relative density for an additional 32 fruit varieties 3 Analytical reference methods 3 Copy of the EU Fruit Juice Directive 3 List of additives allowed in juices and nectars 3 Overview of fruit names in 10 EU languages Figure: Standard composition data sources: USDA National Nutrient Database for Standard Reference record for Apple juice, canned or bottled, unsweetened, without added ascorbic acid NDB No: 09016 (Nutrient values and weights are for edible portion)

Nutrient Unit /100 g No. SD Water g 88.24 45 0.091 Energy kcal 46 0 0 Energy kJ 191 0 0 Protein g 0.10 3 0.008 Total lipid (fat) g 0.13 4 0.013

Ash g 0.23 4 0.027 Carbohydrate, by difference g 11.30 0 0

Fiber, total dietary g 0.2 3 0.106

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Sugars, total g 9.62 4 0.128 Sucrose g 1.26 4 0.023 Glucose (dextrose) g 2.63 4 0.035

Fructose g 5.73 4 0.089 Calcium, Ca mg 8 57 0.464 Iron, Fe mg 0.12 56 0.006 Magnesium, Mg mg 5 58 0.074

Phosphorus, P mg 7 59 0.162 Potassium, K mg 101 58 1.077 Vitamin C mg 0.9 8 0.179

Figure: Standard composition data sources: Nutrition tables - Siegfried W. Souci • W. Fachmann • Heinrich Kraut: Food Composition and Nutrition Tables, Stuttgart 2000, CRC Press

Figure: The A.I.J.N. Code of Practice for the Evaluation of Fruit and Vegetable Juice, Apple juice Reference

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4 Traceability, food labeling, fraudulent imitations of products and false declarations of geographic origin

4.I Terms Traceability refers to the completeness of the information about every step in a process chain. The formal definition is: Traceability is ability to chronologically interrelate the uniquely identifiable entities in a way that is verifiable. In food processing (meat processing, fresh produce processing), the term traceability refers to the recording through means of barcodes or RFID tags & other tracking media, all movement of product and steps within the production process. One of the key reasons this is such a critical point is in instances where an issue of contamination arises, and a recall is required. Where traceability has been closely adhered to, it is possible to identify, by precise date/time & exact location which goods must be recalled, and which are safe, potentially saving millions of dollars in the recall process. Traceability within the food processing industry is also utilised to identify key high production & quality areas of a business, versus those of low return, and where points in the production process may be improved. The European Union's General Food Law came into force in 2002, making traceability compulsory for food and feed operators and requiring those businesses to implement traceability systems. The EU introduced its Trade Control and Expert System, or TRACES, in April 2004. The system provides a central database to track movement of animals within the EU and from third countries.10 The EU project TRACE aims to improve the health and well-being of European citizens by delivering improved traceability of food products11. The several subproject are included into the scheme:

• A review of state-of-the-art with respect to traceability systems and technologies for batch identification, data carrying, and information loss in generic food chains: key issues addressed will be respective merits of barcode, RF-ID tags (active or passive), cost/benefit of 'real' unique identification as opposed to current practice, EAN128 vs. EPC.

• Draft XML-based generic ‘request-response’ scheme deals with, and helps solve one of the biggest obstacles to cheap and efficient dissemination of traceability data in that with a multitude of systems, software and formats, there is currently no standard way of electronically coding and transmitting traceability data.

• The 'Good Traceability Practice' will provide a much-needed guide for the food industry and address key issues such as batch identification, identification of generic 'Critical Traceability Points’.

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• Demonstration activities are planned to demonstrate the developed traceability infrastructure in several food sectors.

4.II Sudan I crisis Sudan I (also commonly known as CI Solvent Yellow 14 and Solvent Orange R), is a lysochrome, an diazo-conjugate dye with a chemical formula of 1-phenylazo-2-naphthol. Sudan I is a powdered substance with an orange-red appearance. The additive is mainly used to colour waxes, oils, petrol, solvents and polishes. Sudan I has also been adopted for colouring various foodstuffs, including particular brands of curry powder and chili powder, although the use of Sudan I in foods is now banned in many countries because Sudan I, Sudan III, and Sudan IV have been classified as category 3 carcinogens by the International Agency for Research on Cancer. In February 2005, Sudan I became a prominent news topic, particularly in the United Kingdom. A Worcestershire sauce produced by Premier Foods was found to be contaminated by the carcinogenic dye. The origin was traced to adulterated chili powder. The sauce was used in hundreds of supermarket products such as pizzas and ready-made meals, and the contamination led to over 400 products being taken off the shelves Due to the failure of traceability of system:

• Huge withdrawal and recall of samples (with delay)

• Yet more than 600 products finally identified as Sudan I positive after 8 month

• The total price for food industry £100-200 milion

• 1395 news in media within first 3 weeks

4.III Geographical indications and traditional specialities The following EU schemes encourage diverse agricultural production, protect product names from misuse and imitation and help consumers by giving them information concerning the specific character of the products12: PDO (protected designation of origin) and - covers agricultural products and foodstuffs which are produced, processed and prepared in a given geographical area using recognised know-how. PGI (protected geographical indication – covers agricultural products and foodstuffs closely linked to the geographical area. At least one of the stages of production,

processing or preparation takes place in the area. TSG (traditional speciality guaranteed) - highlights traditional character, either in the composition or means of production Fig. DOOR - Database of Origin and Registration12

The traceability break down

Sudan I

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4.IV Tracing the geographical origin There are a number of driving forces for reliable analytical methods to verify the provenance of the food we eat. The UK Food Standards Agency (FSA) has consulted the public on a number of key issues relating to food labelling. The FSA's findings clearly demonstrated that ‘country of origin labelling’ was ‘high on the consumers list of demands for change’. There is growing enthusiasm among consumers for high quality food with a clear regional identity. The reasons for this vary from (a) patriotism; (b) specific culinary, organoleptic qualities, or purported health benefits associated with regional products; (c) a decreased confidence in the quality and safety of foods produced outside their local region, country or the EU or (d) concern about animal welfare and ‘environmentally friendly’ production methods. Food scares such as BSE, Foot and Mouth disease, chicken influenza and the malpractices of some international food producers have added to public sensitivity regarding the validity of food origin labelling. As well as heightened consumer awareness there are a number of important legislative driving forces for reliable analytical techniques to verify food provenance. The European Union Protected Food Names Schemes came into force in 1992 (Council Regulation (EEC) No 2081/92, 1992 Council Regulation (EEC) No 2081/92, On the protection of geographical indications and designations of origin for agricultural products and foodstuffs).Council Regulation (EEC) No 2081/92, 1992) and offers an independent inspection and labelling system for the protection of food names on a geographical basis, comparable to the French system ‘Appellation d'Origine Contrôleé (AOC)’ used for wine. There are three schemes; Protected Designation of Origin (PDO), Protected Geographical Indication (PGI) and Certificate of Specific Character (CSC) (also known as Traditional Speciality Guaranteed). PDO is the term used to describe foodstuffs, with a strong regional identity, that are produced, processed and prepared in a specific geographical area using prescribed techniques that may be unique to that region, e.g. Camembert de Normandie, Orkney beef and Umbrian olive oil. Foods with PGI status must have a geographical link in at least one of the stages of production, processing or preparation, e.g. Clare Island Salmon, Sorrento Lemons and Nürnberger Bratwürste. A CSC does not refer to a specific geographical origin, but defines traditional character, either in terms of production techniques or composition.

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Manufacturers of Protected foods usually charge a premium for their produce due to increased production costs and consequently economic incentives exist to replace genuine articles with inferior ones for financial gain. A growing number of research articles have been published in the last 5 years detailing the use of natural abundance isotope variation and elemental concentrations as geographic ‘tracers’ to determine the provenance of food. These investigations exploit the systematic global variations of stable hydrogen and oxygen isotope ratios in combination with elemental concentrations, including heavy isotope variations (e.g. strontium-87) and other biogeochemical indicators. Overview of the way in which the relative proportions of the natural abundance of isotope ratios are affected (or fractionated) in the environment and how this can be exploited for food provenance determinations is given in the table13. Table: The gain of isotopic analyses 13 Isotope ratio

Fractionation Information

2H/1H Evaporation, condensation, precipitation Geographical 13C/12C C3 and C4 plants Diet (geographical proxy) 15N/14N Trophic level, marine and terrestrial plants, agricultural

practice Diet (geographical proxy)

18O/16O Evaporation, condensation, precipitation Geographical 34S/32S Bacterial Geographical (marine) 87Sr/86Sr Age of the rock and Rb/Sr ratio Underlying geology,

geographical

5 Fruit juices Fruit juices and nectars represent a food commodity that is very often subjected to adulteration. The development of adulteration procedures corresponded with increase in the volumes of production. The main cases of the adulteration are: 1 Lowering the fruit (solids) content (dilution and addition of sugar and citric acid) 2 The pulpwash addition (for citrus juices) 3 Extension with less expensive varieties (apple, pear, grape) 4 Special cases (undeclared sugar addition, aroma recovery, water quality) Besides the financial gain of the producer the factors affecting the authenticity and quality of fruit juices are:

• continuing economic recession, • not very clear competition in the market of juices, • pressure of distribution chains, import of juices of lower quality ( e.g. some EU producers

often produce “special” products for the Czech market not complying with AIJN), • ongoing development of the market.

In the Czech market there is a relatively high number of adulterated or non-authentic fruit juices declared as 100% fruit juices. The main deviations are: lowering of fruit content (addition of sugars, acids, artificial mixtures), unlabelled sugar addition (usually without lowering of fruit content), pulp wash addition (including pure pulp wash juices), lower refractive index, low quality of water used for reconstitution and others.

5.I An example of the fruit juices authenticity development in the Czech Republic

The aim of the presented paper is to summarize the development of authenticity of orange juices in the Czech market in the last years. The results of analyses obtained throughout the years allow to evaluate the development of methods of adulteration of the commodity. While at the beginning of

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the project in 1996 more cases of “primitive” adulteration were discovered, recently more sophisticated and “technological” (pulp wash addition) adulteration has been found. In 1996 the most common methods of adulteration were:lower refractive index, significant lowering of fruit content, synthetic mixtures, undeclared addition of sugar and unsuitable water used for reconstitution. The general situation was better in 2000; more than 40% of samples complied with the AIJN. The most frequent examples of adulteration were: pulp wash addition (“no names”, discount products), lower refractive index (including the imported juices), undeclared sugar addition and unsuitable water for reconstitution (higher Ca content). The examples of results of two orange juices sold under different names are given in Table. The limited number of selected markers does not allow to evaluate the fruit content in juices; both samples have lower content of potassium, lower content of flavonoids and lower formol number. The fruit content in sample 1 could be about 60–70%, sample 2 is worse with estimated fruit content of about 30–40%. Sugar (sucrose) was added to both samples. Table Results of analyses of selected markers of two “100%” orange juice samples from the Czech market at the end of 2001

Figure: Cluster analysis representing the groups of orange samples analyzed in the Czech Republic in 1996 and 1999/2000

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5.II An example of the confirmation of Aroma Restoration into the Reconstituted Orange and Apple Juices

According to the requirement of the EC-Fruit Juice Directive fruit juice from concentrate must display organoleptic and analytical characteristic at least equivalent to those of an average type of direct juice. In the manufacture of fruit juices, evaporation in the juice concentration process and thermal treatment in the pasteurizing process are critical factors that may contribute to flavor loose or deterioration. For fruit juice manufactured exclusively from one or two kinds of concentrated fruit juice/puree the restoration of aroma is of concentrated fruit juice/puree the restoration of aroma is obligatory (e.g. orange and grapefruit juices from concentrate e.g. orange and grapefruit juices from concentrate). In a mixture of three or more juices/purees the aroma must be present or restored to at least one of the components e.g. apple and grape juices from concentrate and raspberry purée. Balance: Juice production from 1000 kg of oranges: 500 l juice (or 100 l of concentrate) + 1 kg water phase (volatile esters)) + 0.23 kg oil phase (volatile esters and monoterpens) The aim was to propose a simple method for aroma analysis and to select individual volatiles and their typical characteristic to confirm the aroma restoration. A simple, efficient and sensitive method of solid-phase microextraction (SPME) and gas chromatography-mass spectrometry (GC-MS) has been used for the evaluation of volatile compound profile and quantification of individual alcohols, esters and monoterpens in the samples. According to literature search the analyses was focused on the aroma compounds which are believed to make a positive contribution to apple and orange flavor and represent both hodrophilic (esters e.g. butyl acetate and hexyl acetate and alcohols e.g. 1-hexanol) and hydrophobic (limonene) phase (Figure x y ). Conclusions: Orange and apple juices from concentrates has in many cases lower values of esters and terpenes than is mentioned in the literature or would correspond to the proper concentrates dilution and whole aroma recovery Possible reasons are: 1) no or insufficient restoration of juices from concentrates 2) low quality of aromas used for restoration (low or no content of hydrophilic phase) Figure: Chromatogram of orange juice aroma spectrum (main components of orange juice flavor. alpha- pinene, Beta – myrcene, 3- careen, limonene, gama-terpinene, terpinolen, linalool, decanal, valencene) and chromatogram of apple juice aroma spectrum (main components of apple juice flavor: butyl acetate, ethyl-2-metylbutyrate, 1-hexanol, 3-methylbutyl acetate, hexyl acetate, limonene)

Figure: Target aroma compounds content

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6 Fruit and vegetable products

6.I Fruit purees and jams Commercial fruit baby food is a preserved fruit product usually made with fruit purees, sugar, water and variable additives (thickening agents, antioxidants etc.). As the foodstuffs intended for particular nutritional uses, baby foods for infants and young children conforms to a set of strict guidelines e.g. maximum levels for pesticide residues, microbiological contamination, addition of additives, labeling etc. However, being an important supplement to children diet and/or for their progressive adaptation to ordinary food, the nutritional quality of commercial fruit baby food is very important. The aim of this work was to compare declared and real (measured) values of selected nutritive parameters to asses potential adulteration and/or differences between brands of fruit baby foods. The analyses were focuses on the determination of authentic fruit content, identification of sugar and other additives addition, evaluation of the processing on the main quality indices, namely, contents of antioxidant (ascorbic acid, polyphenols, total antioxidant activity by DPPH assay) and time –temperature effort indicators (hydroxymethylfurfural and furfural) . Table: Samples - declared composition of 10 fruit baby foods, According to ingredients lists, in addition to a certain amount of fruit (usually the most expensive part of raw material), majority of these products consist also of sugars, organic acids and artificial thickening agents Producer Fruit flavor Composition per 100g of product Declared fruit

content Hello strawberries fruit content 85g (apple puree, strawberry

puree 20 %), water, sugar, modified starch E 1442, ascorbic acid

85

Hello apples apple puree 85 %, %), water, sugar, modified starch E 1442, ascorbic acid;

85

Hamé bilberries bilberry puree (20 %), apple puree, water, sugar, corn modified starch E 1442, citric

acid, ascorbic acid

35

Hamé apples apple puree (60 %), water, sugar, corn modified starch E 1442, citric acid, ascorbic

acid

60

Hami bilberries apple puree (71 %), bilberry puree (20 %), 91

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apple concentrate, rice flour, ascorbic acid (min. 15 mg)

Hami apple apple puree, ascorbic acid (min. 15 mg) 100 Hipp pears pear puree (50 %), pear juice (46 %), rice

flour, rice starch, ascorbic acid 96

Hipp plum plums (50 %), water, sugar, rice flour, rice starch, ascorbic acid

50

Sunárek strawberries and peaches

apples (58 %), strawberries (20 %), peaches (16 %), apple concentrate (6 %)

100

Sunárek apples apples 100 Discussion on the composition of samples, real fruit content, evaluation of undeclared additives addition : 1) the differences between the estimates and declared values varied slightly (within the relative error of calculation 15 %) 2) only one (No. 8) of the analysed samples failed to contain the fruit content declared on the label 3) some of the samples contained undeclared additives (sweeteners in samples 1 and 6, citric acid in samples 2, 3, 4 and 6 and ascorbic acid in samples 6 and 7). 4) there are big differences in composition and quality of commercial fruit baby food, some samples contain only fruit, another products are diluted with significant amount of sugar, water and starchy fillers or enriched of declared or undeclared sweeteners and organic acids 5) the nutritive values closely correlates with the fruit content in baby food, the highest antioxidation capacity as well as the content of antioxidants was found in the samples with higher fruit content. Fig.: declared a according to AIJN calculated fruit content

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6.II Ketchups and tomato products Ketchup is a preserved vegetable product made with ripened tomatoes (tomato purees), vinegar, sugar, salt, spices and vegetable. The use of the word "ketchup" on product labels is allowed when the product conforms to a set of strict guidelines only. Czech food law (Decree No. 157/2003 of the law No. 110/1997) specifies the minimum of tomato content (as natural tomato soluble solids NTSS) in ketchup being 7 or 10 %, and 25 or 30 total refractive solid content for tomato ketchup and tomato ketchup labelled Prima, Extra, Special, respectively. Quality of ketchup is, similarly as in the case of other tomato products, derived from content and composition of used tomato purees. The aim of the work was to evaluate the procedure for the estimation of NTSS based on the determination of several chemical markers.

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The natural tomato soluble solid content in ketchup was estimated according to content of lycopene, pyroglutamic acid (PCA), glucose, fructose, sucrose, K, Ca, Mg, formol number, colour (L,a,b) and refractive index. Subsequent analyses were done: 1) evaluation of variability of markers 2) correlation of markers with natural tomato soluble solids

3) stability of markers within the processing 4) sensorial evaluation (Fig.) 5) Comparison of natural tomato soluble solids vs. price (Fig.) Table: Concentration of selected markers in 19 ketchups from the market Rf (°brix) Formol

number (ml 0.1M NaOH/100g)

K (mg/100g)

PCA (mg/100g)

Citric acid (mg/100g)

Malic acid (mg/100g)

K1 28.6 60 333 328 518 101 K2 32 48.5 338 316 669 77 K3 28 54.2 416 323 490 118 K4 29.5 27.4 200 142 391 30 K5 28.9 38.9 307 228 786 124 K6 29 45.6 348 256 664 128 K7 26.1 26.9 185 159 319 63 K8 30,8 59 446 374 697 140 K9 32.2 75.4 617 419 775 180 K10 30.2 44.2 314 209 377 41 K11 35 40.3 363 242 596 115 K12 25.8 29.3 180 151 322 48 K13 29.1 40.8 320 226 787 106 K14 26.4 37.4 167 180 292 49 K15 28.6 44.6 334 238 662 90 K16 29.3 49.9 341 274 562 80 K17 25.6 30.7 161 150 218 45 K18 26.8 32.2 209 184 442 77 K19 27.6 53.8 381 289 584 97 Fig. Sensorial analyses of ketchups (preference testing)

PCA K Ca Mg Na Malic acid NTSS 0.94 0.98 0.84 0.98 -0.05 0.89 Citric acid sucrose glucose fructose Total

sugars Formol number

NTSS 0.98 -0.86 0.06 0.31 -0.87 0.96

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Consumer prefers sweet, smooth taste to tomato content

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Fig.: Comparison of natural tomato soluble solids NTSS vs. price

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7 Milk and dairy products Adulteration in market milk implies addition of any substance to normal milk or removal of any of its constituents or both to deceive the consuming public and derive an extra profit from a given volume of milk. The forms of adulteration like addition of water, skimming or removal of fat and addition of fluid skim milk can be detected from specific gravity and fat content. Accidental adulterations in milk or unhygienic and insanitary practices result in the entrance of dirty water, alkalis from detergents, vegetable cells, hair, household dust and dirt, animal urine, dung feed etc. These are usually detected visually or on the basis of smell and taste2. There are several reasons why detection of the concentrations of cow, goat and ewe milk is of importance. Pure products of goat milk may be used as a supplement of milk for humans who are born with allergic reactions towards cow milk. Some mixed milk products are produced with regard to specifications which specify the mixture of milk from cow, goat and/or ewe. Professionals and consumers want to control the origin of milk in order to be sure that they get products following specifications and labelling. Farmers producing more than one type of milk might be tempted to add cow milk to goat or ewe milk as this would result in higher quantities of the better paid milk variants.

7.I The cases of milk and dairy product authenticity issues 1. Non compliance with legal requirements (product standards) such as:

• Max/min content of water, solid-non-fats and fat in cartain dairy products (butter, cheese, yoghurt)

• Geographical origin of the product 2. Wrongful addition of certain ingredients of dairy or non-dairy origin such as • Watering of milk • Milk of different species • Addition of non-diary protein • Addition of vegetable or animal fats to milk fat • Addition of reconstituted milk to fluid milk 3. Non-compliance regarding use of certain technological process • Heat treatment

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• Cheese ripening • Membrane technology

Legislative requirements:

• Council Regulation (EC) No 1255/1999 of 17 May 1999 on the common organisation of the market in milk and milk products

• Commission Regulation (EC) No 273/2008 of 5 March 2008 laying down detailed rules for

the application of Council Regulation (EC) No 1255/1999 as regards methods for the analysis and quality evaluation of milk and milk products

The examples of reference methods according to regulation dealing with the milk and milk product authenticity are: Detection of buttermilk, Determination of skimmed-milk powder content, Detection of starch, Determination of milk fat purity. Table: Analytes of indicative value for the detection of adulteration of milk and milk product Chyba!

Záložka není definována. Milk component

Source of adulteration Analyse (s)

Fat Non-dairy fat or milk Buttermilk added to milk

Fatty acids, triglycerides (TAG), phospholipids, sterols

Protein Non-dairy proteins Milk of a different species Whey added to milk Heat load

Caseins, whey proteins, denaturated proteins, glucomacropeptide

Lactose Water Heat load

Freezing point, furosin, lysinoalanine, HMF

Minerals Water Freezing point Milk fat in the form of butter or ghee is often extended by other fats and this is extensively discussed in the scientific literature . Large price difference between butter fat and substitutes prompts this adulteration. Vegetable oils, mainly cottonseed, and beef tallow are common substitutes for butter fat. The detections are generally based on composition and structure of triglycerides, fatty acids, composition of unsaponifiable matter, that is, sterols, sterol esters, hydrocarbons, tocopherols. Table: Average composition of authentic milk fat Fatty acid Average content

in authentic milk fat

TAG Average contetn in authentic milk fat (g/100g)

SD

C 4:0 8-11% C24 0.04 0.004 C 6:0 1-5% C26 0.26 0.007 C 8:0 1-3% C28 0.66 0.02 C 10:0 2-5% C30 1.31 0.023 C 12:0 3-6% C32 2.92 0.03 C 14:0 9-14% C34 6.73 0.053 C 18:0 8-14% C36 12.12 0.03 C 20:0 0-1% C38 12.92 0.054 C 18:1 17-26% C40 9.7 0.019 C 18:2 0.3-2.2% C42 7.62 0.02 C 18:3 0.1-0.8% C44 7.35 0.025 C 20:4 0.4-0.6% C46 7.91 0.029

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C48 9.09 0.048 C50 9.97 0.038 C52 7.76 0.042 C54 3.32 0.02

7.II Reference method for the determination of milk fat purity14 This standard specifies a reference method for the determination of milk fat purity using gas chromatographic analysis of triglycerides. Both vegetable fats and animal fats such as beef tallow and lard can be detected. Using defined triglyceride equations, the integrity of milk fat is determined. Basically, the method applies to bulk bovine milk, or products made thereof, irrespective of feeding, breed or lactation conditions. Only exceptionally high feeding of pure vegetable oils, such as rapeseed oil, can result in a false positive result. Milk products obtained from individual cows can also cause a false positive result. In particular, the method is applicable to fat extracted from milk products purporting to contain pure milk fat with unchanged composition, such as butter, cream, milk, and milk powder. Technological treatment of milk fat such as removal of cholesterol or fractionation can cause a false positive result. This is also true for milk fat obtained from skim milk or buttermilk. The method is not always applicable to fat extracted from cheese, because the ripening process can affect the fat composition so strongly that a false positive result is obtained. PRINCIPLE OF THE METHOD: The fat extracted from milk or milk products is analysed by gas chromatography using a packed or a short capillary column to determine the triglycerides (TGs), separated by total carbon numbers. By inserting the mass fraction, expressed as a percentage, of fat molecules of different sizes (C24 to C54, using even C numbers only) into suitable TG equations, S-values are calculated. If the S-values exceed the limits established with pure milk fat, the presence of foreign fat is detected.

Fig.: Example of TAG profile of authentic milk fat

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Fig.: Calculated the mass fraction of each TG (for i = C24, C26, C28, C30, C32, C34, C36, C38, C40, C42, C44, C46, C48, C50, C52, and C54) plus cholesterol, wi, expressed as a percentage, of the total TG content of the test sample. Calculate the S-values, expressed as a percentage, by inserting the calculated wi of the appropriate TG percentages. Use all equations irrespective of the kind of foreign fat suspected.

Fig. S limits for pure milk fat The official Italian methods of testing butter for adulteration are based on the ratio of fatty acids. The indices for unadulterated butter, along with their limits are2 C4/(C6+C8) 0,7 -1,7 C12/C10 0,9-1,3 C14/C12 > 2,7 C18 unsaturated/C18 saturated 2-3

8 Fats and vegetable oils The major vegetable oils used the world over for edible applications are derived from groundnut, soybean, sunflower, rapeseed, mustard, sesame and safflower seeds grown primarily as annual oil seed crops and oil palm, coconut and olive which are perennial trees. Cottonseed has of late been processed to exploit the oil for edible uses. Similarly corn germ and rice bran are valuable by

25

products of the staple cereals that yield edible oils, the former being a recognized quality oil of commerce. Cocoa butter and avocado fruit fat are speciality fruit fats of plant origin. Fats of animal origin emanate as by products of beef and pork processing in large quantities. Their refined forms are extensively used as edible fats. Milk fat in the form of cream, butter, butter oil and ghee is used worldwide in diverse food products. Marine oils, as such or after controlled hydrogenation find use in canning of fish types. These oils and fats, whether of animal or plant origin may be used in the mechanically extracted or solvent extracted forms or after further processing like deodorization, decolorization, refining, hydrogenation or fractionation such as winterization.

8.I The cases of vegetable oil authenticity issues : • Addition of less expensive oil into the more expensive • Non-compliance regarding use of certain technological process (cold pressed only by

mechanical mean, extracted, refined) • Mislabeling of olive oil origin

The price of vegetable oil (year 2004, according to United States Department of Agriculture www.usda.gov and International Olive Oil Council http://www.internationaloliveoil.org) Vegetable oil Price (US dolarů/kg) cottonseed 0.64 coconut 0.49 linen 0.67 olive 3.2 pomace olive 2 Extra virgin olive 3.6 palm 0.47 groudnut 1.32 rapeseed 0.62 sunflower 0.63 soya 0.6

The methods for the vegetable oil authenticity evaluation:

• Basic quality tests (iodine number, acidity number, free glycerole, colout, peroxine number, anidisine number, thiobarbituric number, spectrum in UV)

• Sterols • Fatty acids • Triacylglycerols • Natural isotopes ratio • Organoleptic evaluation

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Fig.: Fatty acids profile Spanish Toxic Oil Syndrome Epidemiological data clearly indicate an association between the consumption of industrial rapeseed oil adulterated with aniline and the subsequent development of acute pulmonary and chronic neuromuscular disorders in Spanish Toxic Oil Syndrome. It is estimated that about 50 000-100 000 people consumed the poisoned oil which affected over 20 000 people and has caused many deaths2.

8.II Olive oil Compared to other vegetable oils, olive oil is relatively expensive. In the EU, eights grades of olive oil exist of which four may be sold to consumers. The quality grade of an olive oil sample is lai down in Commission Regulation (EEC) No 2568/91 of 11 July 1991 on the characteristics of olive oil and olive-residue oil and on the relevant methods of analysis. Criteria: Markers of hydrolyses Markers of oxidation Organoleptic assessment Purity control (presence of refined oil, detection of foreign oils, presence of olive pomace oil

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Table: Regulation EC 1638/98 definitions of olive oils Methods of analyses:

• Determination of free fatty acids, cold method • Determination of the peroxide value • Determination of wax content by capillary column gas-liquid chromatography • Determination of the composition and content of sterols by capillary-column gas

chromatography • Determination of erythrodiol and uvaol • Determination of the percentage of 2-glyceryl monopalmitate • Determination of composition of trilinolein • Spectrophotometric investigation in the ultraviolet • Analysis by gas chromatography of methyl esters of fatty acids • Determination of the volatile halogenated solvents of olive oil • Organoleptic assessment of virgin olive oil • Method for determining aliphatic alcohol content • Oil content of olive residue • Determination of iodine value • Determination of stigmastadienes in vegetable oils • Method for determining the content of triglycerides with ECN42

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Figure: Decision tree to determine the quality and purity of extra virgin olive oil

9 Meat and meat products By Prof. Ing. Petr Pipek, CSc.

Meat is defined as all edible parts of animals suitable to human consumption including fishes and vertebrates. Following this definition we can see as meat also animal fats, blood, bones and meat products. In narrow sense, muscle tissue is seen to be meat. Meat intended to human consumption must be approved by veterinarian inspection.

In principle all species of animals can serve as source of meat, but only several animals are suitable in all aspects (sensory, nutritional, economical and ecological). Meat for human consumption can be provided on two ways: or by hunting or by breeding and slaughtering of domesticated animals, the second one is prevailing.

In the opposite different meat replacers of vegetable origin (soy proteins, saccharides, gums etc.), viscera and mechanically recovered meat can not be labelled as meat.

“Meat” as raw material for meat product and for the calculation of the “meat content” means only the muscle tissue including a limited ratio of the interstitial fat and connective tissue.

“Meat products” means a food containing as prevalent raw material meat. As adulteration can be seen different illegal and/or unmoral treatment, raw material

replacement and low quality masking including not objective information in advertising and incomplete labelling of meat and meat products. Different examples of the adulteration can be presented, such as animal species substitution/confusion, body parts confusion, replacement of meat by other raw materials illusion of freshness, substitution of fresh meat by frozen/defrosted one, colouring, etc.

Adulteration is of course also the retouch of date of expiration on the labels or extreme spicing of products with sensory markers of spoilage. In extreme fall the use the perished animals was observed.

It should be accented, that adulteration concern not only legislacy but also the ethics of producer to consumer the second item being more insidious.

9.I Adulteration of meat Adulteration of intact meat occurs during selling of carcasses, their parts, in the meat retail

in shops and supermarkets or during culinary preparation in restaurants and/or in eating places. An advantage is that the customer can see the appearance of such meat and estimate its quality. In opposite the problem arises at ground meat that can be modified and contain different additives.

Composition of meat

Meat contains in large range water, proteins, lipids, minerals and extractive compounds. Proteins in meat are mostly "full valuable", i.e. they contain all essential amino acids. Content of pure muscle protein (i.e. sarcoplasmic and myofibrillar) is a marker of meat content and important quality parameter. It is determined indirectly (total protein by Kjehldahl minus collagen content determined by hydroxyproline content) or direct method (content of 3-methylhistidine by chromatography).

In the case of retail meat the appearance, marbling (intramuscular fat) and colour are important parameters too. The freshness and safety of meat is obvious premise of the use of meat. Examples of meat adulteration 1) Animal species. The goal of replacement of one animal species by other one is to use cheaper meat, to compensate lack several species (e.g. game) etc. There is also a danger to eat the meat that is not acceptable from religious or ethical reasons and can cause psychical trauma to consumer although it is safe and nutritional valuable. The confusion of animal species can be caused wilfully

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or as a consequence of improper cleaning of the machines after processing another meat species. The animal species of the meat can be estimated visually by colour, shape and size. To exact detection different objective methods are used such as PCR, ELISA, electrophoresis of proteins (mostly haem pigments), histology etc. The following species confusions can be mentioned:

a. Use of pork for ethnics that refuse it - Jews and Muslims. (Orthodox Jews request “Kosher certificate”).

b. Replacement of horse by or beef contrariwise. Horse meat was seen in the past as less valuable (emergency slaughter) and it is not acceptable for some persons (ethical reason). In present it is used as raw materials for meat products; it is correct if adequately labelled.

c. Use of wall fish meat instead of beef. It was problem in the past when wall fish meat was a cheap off fall, today the hunting of wall fish is limited/prohibited.

d. Replacement of game (deer, venison, mouflon, wild pigs) by the cheaper similar meat of home animals (cattle, sheep, pig).

e. Confusion of liver of different animals (beef vs. pork vs. poultry) – mostly in meat products (see later).

f. Replacement or mixing of pork by turkey and/or chicken. g. Use of the meat of dogs, cats and monkeys instead of the meat of home animals. In such

case the enormous health danger and the psychical trauma threats to consumer. h. Replacement or mixing of isolated fats – typical is the addition of cheap beef tallow to pork

lard. Exact analytical methods (chromatography) or presence of carotenoids can discover such falsification.

2) Sex and age of animals. This confusion is frequent in the case of beef, as the quality is very different being lower at cows. There is the possible to use the meat of old cows’ (potentially a source of BSE) instead of meat of young bulls, steers or heifer. The detection of such confusion is possible using PCR. Boars are not suitable for pork because of boar off flavour caused by scatol and androstenon, although their production is more economical due to anabolic effect of male hormones. Thus female and castrated male are used for pork production. The boar off flavour can be detected by GLC.

3) Anatomical parts. The substitution of different anatomical parts can be hardly detected, mostly by anatomical shape and size, eventually using histology. Classical and popular example is the replacement of beef tenderloin (musculus psoas major) by other muscles, e.g. these from shoulder (musculus supraspinatus a trapezius), those received also the name “sham” or “Jewish tenderloin”.

4) Water addition to retail meat. Excessive injection of water can be seen as adulteration; in the contrary if correctly labelled, the brine (20 % water+E450) injection to meat can increase the meat tenderness and thus its common quality. The analysis is very simple, because the water content in meat is nearly 70 % and its relation to protein content (“Feder number”) is nearly 3.5 %. This meat tenderisation is a positive trend to quality under presumption of the adequate price and labelling.

5) Replacement of meat by other materials can be expected only in the case of ground meat. The problem is similar as at the meat products (see bellow).

6) Colouring of meat should evoke an impression that it is a fresh, optimally aged muscle tissue; in the case of ground meat it should imagine the higher lean meat content. Mostly the allowed colourants (cochineal, betalains) are used, but the addition of prohibited ones (e.g. erythrosine) was also detected. On this way it is also possible to mask the discolorations caused by haem pigment oxidation or the microbial spoilage of meat. The presence of colourant can be detected after adequate separation (extraction or chromatography) and measurement of its spectrum. Use of the suitable lighting of shelf in supermarkets can create an impression of better colour; it is not falsification in the true sense, but it influenced the customer psychic and he can pass over the worse quality.

7) MAP – packaging in the modified atmosphere. It is a special topic when the blooming of meat surface by oxygen creates an excellent bright red colour of oxymyoglobin or

30

oxyhemoglobin. This nice appearance is only contemporary and soon the discolorations happen due to the oxidation of lipids and haem pigments. The use of carbon monoxide forms the stable colour and prevents lipids oxidation; it is not allowed in EU because of suspected masking of the meat spoilage. It is a fact that carbon monoxide did not mask the discoloration but it prevents it. Carbon monoxide is allowed to use to MPA in USA, Japan and Norway. Detection is possible using the meat colour evaluation and by atmosphere analysis.

8) Mask of spoilage. Beside of colouring all treatment leading to the impression of false better quality or masking the starting spoilage can be seen as adulteration; in case of pathogen incidence it can have fatal consequences. An example is excessive flavouring (mostly sharp spices) or use of citric grass that evokes an impression of freshness.

9) Misuse of preservatives. Replacement of GMP and high level of hygiene by unnecessary addition of bacteriocins, organic salt etc. is another example of falsification. In the contrary they can be used to increase the production security.

9.II Adulteration of meat products. The main raw material for meat products is meat. The most frequent adulteration the

replacement of meat by other cheap components, they are often of vegetable origin. They can improve the technological, in some case even sensory properties; problem is that in most case the content of quality meat must be reduced. All meat replacers can be determined by special methods, such as chromatography, immunomethods, spectrophotometry of different markers, and by histology (combination with video image analysis) etc.

The composition of meat products can be evaluated by the water, fat and protein content. Pure muscle protein content seems to be most objective criterion to estimate meat content. Pure muscle proteins can be determined indirect as the difference total protein content (Kjehldahl method) minus collagen content (spectrophotometry method of hydroxyprolinu determination); unfortunately many other amino compounds, such as vegetable proteins, urea, and amines can be determined as virtual muscle proteins. New chromatographic direct method uses 3-methylhistidine (present only in myofibrillar proteins) content as marker of muscle proteins.

In EU states there is a special complicated algorithm to calculate the meat content in meat products. It supposes that meat contain less connective tissue as 25 % and fat content is les then 25 % at beef and 30 % at pork). Several meat products (especially traditionally ones) have to have a certain minimal meat content.

Special analyses are used at long-life sausages. Its long shelf-life is assured by drying, i.e. by the lowering of water activity. In this case the maximal fat content (Soxhlet method) and water activity are measured.

Meat products can be adulterated also by the same methods as mentioned above. A short survey of meat replacers and additives follows:

1. Proteins. Different vegetable and animal protein are added to improve technological properties and/or to replace meat and on this way to reduce material costs. As they are mostly white, the increase of the meat products lightness must be compensated by the colourants addition. Determination is possibly immunologically, by electrophoresis, chromatographically. Chemical methods of (soy) proteins are based also on analysis of tracer substances accompanying the proteins.

a. Soy proteins occur as concentrates or isolates. They have relative good properties, an acceptable amino acid composition; their handicap is “bean off flavor” and possible allergenic effect.

b. Pea proteins are similar to foregoing ones, less used. c. Mustard proteins d. Lupin (Lupinus) protein e. Milk proteins have been traditional raw material for meat products in different forms:

31

raw milk, dried skimmed milk, cream, casein (or caseinate), whey and coprecipitates. Their disadvantage is relative high price.

f. Blood proteins have been traditionally used for cooked meat products mostly as full blood; recently different fractions of blood are offered: plasma, erythrocytal fraction, and globin. They are (pork) sarcoplasmatic proteins, from this reason they need usually not be labelled and they are detected as “pork protein”. Haemoglobin can be used as colourant too.

g. Collagen preparatives originate mostly from pig skin. They have good technological properties, they are cheap, but they don’t contribute to “pure muscle proteins” content. Isolated collagen or swelled skins are used.

2. Mechanically separated meat - MSM (or mechanically recovered meat). The original idea

was to safe the rests of muscle on the bones and to avoid bones and other hard particles from fishes. Enormous production of MSM in poultry industry evoked its use into meat products. Different positives (WHC, glycoprotein’s content, low price) and negative (limited shelf-life, worse flavour, oxidation, bone particles) aspects can be discussed. MSM is not seen as “meat” and thus it must be properly labeled in the list of raw materials. An ethical problem is that most consumers don’t know what MSM is and they suppose that it is received by sophisticated robots in top hygiene. Use of MSM from cattle spinal column is not allowed because of BSE. Detection of MSM is possible using video image analysis of histological preparation after adequate colouring (e.g. alizarin). Chemical method uses determination of calcium content that is ten times higher at MSM opposite to normal meat.

3. Saccharides. The purpose of the use of saccharides is to modify technological properties (WBC, reduction of mass losses) and to reduce material costs. Polysaccharides are able to bound high amount of water. They are determined by adequate apparative or separation methods (chromatography) or calculated as the rest after the water, minerals, proteins and lipids determination. Starch (potatoes, wheat, maize, tapioca), carrageenans, fibre (cellulose and pectin from potatoes, citruses, apple, carrots etc.) and different gums are used

4. Other chemical additives can improve technological and sensory quality of meat products; this use is regulated by legislation and they must be exactly labeled. They are detected or determined mostly by separation techniques (chromatography) or spectrophotometry.

a. Phosphates (E450-2) increase WHC, reduce water losses and help to emulsify the lipids. The misuse, i.e. excessive addition, omit of labeling and addition in the meat products for children (e.g. “baby ham”) is real adulteration, although this additive can be positive in the quality.

b. Nitrites (E250) or nitrates (E252) are traditional additives to produce the pink colour of meat products. Their addition is regulated and consistently determined, mostly by spectrometry.

c. Glutamate (E621) is used to increase the meaty flavour. If properly labeled there are no legislative problems; the necessity to mask the lower meaty flavour, i.e. lower meat content is an offence against ethic.

d. Glukono-delta-lacton (E575) is used to accelerate the pH decline of fermented sausages during ripening. On this way cheaper fermented sausages of lower sensory quality can be produced.

Conclusion

Although many attempt of falsification of meat products have been noticed in the past, the strict regulations and consistent inspection assure the corresponding quality of products and avoid the falsification. As the main ethical problem is the reduction of meat content in cheap meat product; the customer must be aware that there are economical limits in the price reduction and it is impossible to produce the extreme cheap products with high meat content.

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10 Tea and coffee

10.I Tea and tea based products Due to its taste, together with its refreshing and mildly stimulant effect, tea, produced from the leaves of Camelia sinensis, is the most widely consumed beverage in the world. In addition, the positive health effects of tea have been recognized since ancient times. Tea consumption has been implicated in lowering the relative risk of stomach, esophageal and lung cancer, as well as in reducing the incidence of stroke, lowering the atherogenic index and improving liver functioning ). The main types of tea are distinguished by the type of fermentation processing they undergo; green tea is not fermented, black tea is almost completely fermented, and Oolong tea is only partially fermented. Tea leaves and prepared infusions usually vary greatly in quality, not only according to type, but also due to variety, geographic origin, processing technology used and other factors. The main cases of the adulteration are:

• The different origin of tea (declared from preferable origins e.g. Kenya, Assam, Darjeeling) • Exhausted tea leaves, different parts of tea plant or other leaves added (yerba mate, licorice,

chamomile, chestnut husk) • The different manufacturing procedure (Orthodox method or CTC – Crushing, Tearing,

Curling, the way of decaffeination) • The lowering of the content of tea in tea-based products

Requirements for the quality of tea leaves and tea-based beverages are determined by individual national standards and directives, some of which are summarised in Table . Table: Important qualitative parameters of tea and tea-based products according to various legislative requirements Product Parameter Cz Rep* Slovakia** Germany*** Austria****

Total ash (max., %) 8 8 1 ***** 1* Water extract (min., %) 25 25 x 32 Moisture (max., %) 10 10 8 8

Tea

Caffeine in decaffeinated tea (max.)

x 0.4 g / 100 g 0.4 % in dry matter

0.4 % in dry matter

Tea extract (dry matter) in beverage (min.)

x x 1.2 g/l 0.12 %

Caffeine in dry matter / beverage (min.)

x x 1.5 % / x 1.5 % / 40 mg/l

Tea-based products

Caffeine in decaffeinated tea extracts (max.)

x 1.2 g / 100 g 1.2 % 1.2 %

* Czech Food Code No. 110/1997 Col. and decree No. 330/1997 Col. as amended. ** The Food Code of the Slovak Republic, chapter 24 *** German Food Code, BAnz. No. 66a from 29.4.1999 **** Austria Food Code, decree B31 *****Insoluble in acid

10.II Methods of tea authenticity testing The quality of tea or tea extract can be characterized by basic chemical composition e.g. determination of total ash, moisture and water extract content. The presence of material other than that which is truly tea can be relatively simply examined by macroscopic and microscopic analyses. Authentication in terms of type and origin is more difficult. There is a multitude of specialize teas produces in specific areas, by particular processes or flavored in various ways which can be distinguished mainly by sensory analyses1:

33

• Assam - makes up the largest volume of tea and is mostly grown in the Assam region of Eastern India, the teas have a good depth of flavor and richness of color

• Darjeeling – tea form the north –east of India (Himalayas foothills), high-priced tea, considered as the finest speciality tae, produces a pale liquor and has a delicate muscatel-like flavor, adulteration and falsification are serious problems in the global tea trade; the amount of tea sold worldwide as Darjeeling every year greatly exceeds the annual tea production of Darjeeling, which is estimated at 11,000 tones.

• Kenyan teas are considered as being of good quality • Oolong a fine tea from China or Taiwan with peachy flavor and reddish liquor

Apart from sensory evaluation, chemical analysis is the most reliable method for evaluating the quality of tea and for confirming the presence of tea in infusions. Several studies have identified chemical markers that positively correlate with the quality of tea, the most important of these being the following: catechin content and compositioncaffeine content, theobromine content, , and free amino acid content and composition . The antioxidant activity of tea extracts is primarily attributed to the role of the catechins, which as the most abundant polyphenols in tea, constitute up to 25% of its dry weight. The major catechins in tea are catechin, epicatechin, epigallocatechin and epicatechin gallate, together with their fermentation products, the theaflavins and thearubigins. While dry green and black teas contain comparable amounts of polyphenols, in green tea these mainly consist of catechins; catechins in green tea being approximately 3.5 times higher than in black tea. As tea leaves are fermented, the amount of theaflavins and thearubigins increase, while catechins content decreases. Polyphenols are generally responsible for tea’s slightly bitter and astringent flavour, and theaflavins and thearubigins for the brownish colour of black tea infusions

10.III The content of tea in tea-based products In recent times tea-based products such as iced teas and instant teas have become more and more popular, combining the advantages of traditional leaf infusions, such as taste, refreshment, stimulation and a healthy effect, with the benefit of convenient preparation. In addition to a certain amount of tea extract, these products mainly consist of sugars, organic acids and artificial flavourings. However, as in the case of leaf tea, the quality of these tea-based beverages is likewise based on the content and composition of the tea extract used in their production. The aim of this study is to propose a method for estimating tea content in tea-based products. This methodology involves the following steps: 1. Selection of chemical markers of the quality and authenticity of tea and tea-based products. 2. Selection of the relevant analytical methods. 3. Determination of variation of type, origin and quality among green and black leaf teas, and evaluation of their possible markers. 4. Analyses of samples of tea-based drinks for their theobromine, caffeine, theanine and total polyphenol content. 5. Calculation of tea content according to both average literature data and the mean experimental data obtained for samples of leaf tea. Fig: Tea content in tea-based products

34

0,0

0,2

0,4

0,6

0,8

1,0

1,2

1,4

1,6

1,8

2,0

29 30 31 32 1N 2N 3N 4N 5N 6N 7N 8N 9N 10N 35 11N

12N

13N

14N

15N

16N

17N

18N

19N 33 34

Tea

con

tent

(%)

Tea content according to literature dataTea content according to experimental dataTea content declared by producer

The content of tea in tea-based beverages can be estimated according to the caffeine, theobromine, theanine and total polyphenols content of these products. Due to its stability and low variability within the analyzed set of samples (1.6 g/ 100g and 1.3 g/100g for green and black teas respectively), the amino acid theanine appears to be a particularly promising marker of tea quality and authenticity. However, to obtain an accurate estimation of tea content, the values of several analytes must be determined. The mean values used in the calculation of tea content often vary widely in the literature, but, based on our experiments, we propose use of the following averages for caffeine, theobromine, theanine and polyphenols: for black tea-based products 1909 mg/100g, 129 mg/100g, 1261 mg/100g and 9116 mg/100g respectively; for green tea-based products 1886 mg/100g, 161 mg/100g, 1652 mg/100g and 14663 mg/100g respectively. These data correspond with the published values, but would need to be verified at the time of use to take into account potential changes in the quality of teas used in the production of tea-based beverages. Approximately one third of the analysed samples failed to contain the tea extract levels required by German and Austrian legislation, while 10 % were not in compliance with the less demanding Czech legislative requirements.

10.IV Coffee The two species of economic significance in global coffee trade are Coffea arabica (arabica) and C. canephora (robusta). Arabicas command a higher price and are considered to be of better quality than robustas. However, what defines coffee quality is often subjective, and many commercial coffees are blends of the two species. Furthermore, coffees are processed, prepared, and consumed in a variety of ways according to local practices. Examples are "French" coffees that contain added chicory, or "Viennese" coffees containing fig. Green coffee quality, processing, the level of defects, roasting, and grinding influence the final product. Soluble (Instant) coffees are further subjected to an assortment of extraction, concentration, and drying processes15. Methods for detecting adulteration have focused on

• extraneous sugars from undeclared chicory, cereals, roasted beans, the dried root of wild endive, a plant of the dandelion family or other fillers

35

• geographical origin • quality measures such as the percentage of robusta in a blend, • the levels of defects (coffee parchment, husks, discolored beans) • undeclared manufacturing procedure (the way of decaffeination) • the similarly in the case of instant coffee

Requirements for the quality of coffee and coffee based products are determined by both individual national standards and EU directives (DIRECTIVE 1999/4/EC relating to coffee extracts and chicory extracts, International Coffee Organisation, ISO) some of which are summarised in Table Table: Important qualitative parameters of coffee

Product Specification Caffeine in DM (% )

Water extract in DM (min. %)

Moisture (max.

%)

Roasted coffee

green coffee roasted of any degree and includes ground coffee

min 0.6 22 5

Decaffeinated coffee

means green. roasted or soluble coffee for which caffeine has been extracted

max 0.1 19 5

Coffee extract

obtained by extraction from roasted coffee beans using only water as the medium of extraction and excluding any process of hydrolysis involving the addition of an acid or a base. Apart from those insoluble substances which it is technically impossible to remove. and insoluble oils derived from coffee. coffee extract must contain only the soluble and aromatic constituents of coffee.

min 2.5 - 5

Decaffeinated coffee extract

max 0.3 - 5

10.V Methods of coffee authenticity testing Possible ingredients that may be found in ground coffee or coffee extracts include chicory, malt, figs, cereals, caramel starch, maltodextrins and roasted coffee husks/parchment. . In the case of roasted and ground coffee the microscopy can help. The free and total carbohydrate profiles enable the detection of fraudulent addition of cheaper coffee substituents in commercial products, e.g. the code of practice for the soluble coffee industry in the UK specifies the maximum acceptance levels: total glucose 2,6 %, total xylose 0,6%, free fructose 1,0% for the coffee to be authentic. Table: Influence of the various substituent addition on the carbohydrate composition (%) Coffee fructose glucose Other carbohydrates authentic 0.1 0.51 Total xylose max. 0.4%. free mannitol

max.0.3% + 5.0% chicory 3.25 0.96 + 5.0% caramel 0.39 3.04 + 5.0% cereals <0.1 4.45 + 5.0% malting barley <0.1 4.39 + 5.0% cereals and chicory 0.70 2.86 coffee husks/parchment Increase of xylose above 0.58 and

36

addition mannitol above 0.47 % There are two main species of the coffee plant, Coffea arabica being the older one. While more susceptible to disease, its flavour is considered to be better than the other variety, Coffea canephora (robusta). Robusta, which contains about 40-50 % more caffeine, can be cultivated in environments where arabica will not thrive. This has led to its use as an inexpensive substitute for arabica in many commercial coffee blends. Compared to arabica, the robusta variety tends to be bitter and has little flavor, with a telltale "burnt rubber" or "wet cardboard" aroma and flavor. To distinguish between both varieties and to confirm the proportions of Arabica and Robusta in the blends is generally based on the analyses of lipidic fraction (table). Table: The approaches to the evaluation of the variety composition of coffee blends Analytical determination

Significant parameters for differentiation

Prediction error Chemometrics

Sterolic profile ∆5-avenasterol Prediction error: 1,1 % MLR, PCR, PCA

Unsaponifiable lipid fraction

Diterpenic alcohols profile

Limit of detection (robusta in arabica) 5-10 %

PCA

Diterpenic alcohols a sterols

Kahweol, cafestol, 16-O-methylcafestol, ∆5-avenasterol

none

Sterolic profile ∆5-avenasterol, sitostanol Coomans´weights: avenasterol -6.62, Sitostanol – 2.97

PCA

Tocopherols and TAG

β-tocopherol and γ-tocopherol

PCA and LDA

Fatty acids Fatty acids profile Arabica/robusta rec. ability: 100%

PCA and LDA

Aroma Volatile compounds profile

CA and PCA

Metal content P, Mn and Cu Prediction error: 7 % PCA Trace heavy metals Mn and Zn none

10.VI Differentiation of coffee varieties according to their sterolic profile The aim of the presented work was to differentiate between two important coffee varieties – arabica and robusta by means of chemical analyses of sterolic fraction of 27 roasted coffee samples. After the extraction of the coffee oil, the lipids have been saponified and sterols converted into trimethyl silyl derivatives and analysed by gas chromatography with MS detection. Several statistical approaches were used for the evaluation of authenticity of coffee samples:

1) multilinear regression (A (%) = 117 – 11.1 x ∆5-avenasterol (%)) 2) principal component analyses (Figure) 3) cluster analyses) (Figure)

Figure: Chromatogram of sterolic profile of authentic Arabica and robusta coffee: obtained results confirmed a relatively stable composition of coffee oil from arabica (14.1 %, 21.2 %, 52.2 %, 1.7 % and 9.5 % of campesterol, stigmasterol, sitosterol, ∆5-avenasterol and

37

stigmastenol) and from robusta (14.8 %, 19.3 %, 42.2 %, 9.5 % and 8.9 %) Fig.: Plot for the PCA loadings for the set of samples Fig.: Cluster analysis of the coffee samples

To validate the results obtained for the model samples by the statistical analyses (multilinear regression, principal component analyses a cluster analyses) a test set containing the real coffee samples purchased at the market was considered. Achieved results of all statistical approaches were in a good agreement; the coffees claimed to be of the arabica variety were proved to be authentic. Labeling and composition of all commercial roasted coffee samples fulfilled the requirements of recent Czech legislation. The analyses of sterolic profile of the oil of roasted coffee provide a very useful tool for the evaluation of coffee variety using ∆5-avenasterol as the main marker of arabica/robusta ratio in the sample. Prediction error of classifying the coffee samples according to the suggested correlation of arabica content with the percentage of ∆5-avenasterol is about 8 %.

11 Honey Honey is the natural sweet substance produced by Apis mellifera bees from the nectar of plants or from secretions of living parts of plants or excretions of plant-sucking insects on the living parts of plants, which the bees collect, transform by combining with specific substances of their own, deposit, dehydrate, store and leave in honeycombs to ripen and mature. The main types of honey are as follows (according to origin): 1 blossom honey or nectar honey, honey obtained from the nectar of plants; 2 honeydew honey, honey obtained mainly from excretions of plant sucking insects (Hemiptera) on the living part of plants or secretions of living parts of plants. Honey consists essentially of different sugars, predominantly fructose and glucose as well as other substances such as organic acids, enzymes and solid particles derived from honey collection. The colour of honey varies from nearly colourless to dark brown. The consistency can be fluid, viscous or partly to entirely crystallised. The flavour and aroma vary, but are derived from the plant origin. When placed on the market as honey or used in any product intended for human consumption, honey shall not have added to it any food ingredient, including food additives, nor shall any other additions be made other than honey. Honey must, as far as possible, be free from organic or inorganic matters foreign to its composition. The main cases of the adulteration are:

• Addition of sweet substances • Addition of water

38

• Artificial honey production • Misdescription of botanical source (e.g. misdewscription of blossom and honeydew honey,

of floral source, of geographical and topological source) Requirements for the quality of honey are determined by both individual national standards and EU directive(COUNCIL DIRECTIVE 2001/110/EC relating to honey) ) some of which are summarised in the table Table: Honey composition criteria blossom honey honeydew honey.

blends of honeydew honey with blossom honey

baker's honey

Fructose and glucose content (sum of both) (min)

60.0 45.0 -

Sucrose content (max) 5.01) 5.0 - Moisture content (max) 3) 20.0 20.0 23 Free acid (mekv/ kg max) 50.0 50.0 80 Hydroxymethylfurfural (mg/ kg max) 4)

40.0 40.0 -

Water-insoluble content (% max.)2) 0.10 0.10 - Electrical conductivity (mS/ m) 5) Max 80.0 Min 80.0 - Diastase activity (Schade scale) 6) 8.0 8.0 - 1) false acacia (Robinia pseudoacacia), alfalfa (Medicago sativa), Menzies Banksia (Banksia menziesii), French honeysuckle (Hedysarum), red gum (Eucalyptus camadulensis), leatherwood (Eucryphia lucida, Eucryphia milliganii), Citrus spp. not more than 10 g/100 g —lavender (Lavandula spp.), borage (Borago officinalis) not more than 15 g/100g 2) pressed honey not more than 0,5 g/100 g 3) heather (Calluna) an baker's honey in general not more than 23 % — baker's honey from heather (Calluna) not more than 25 % 4) honeys of declared origin from regions with tropical climate and blends of these honeys not more than 80 mg/kg 5) Vexceptions: strawberry tree (Arbutus unedo), bell heather (Erica), eucalyptus, lime (Tilia spp.), ling heather (Calluna vulgaris), manuka or jelly bush (leptospermum), tea tree (Melaleuca spp.) 6) honeys with low natural enzyme content (e.g. citrus honeys) and an HMF content of not more than 15 mg/kg not less than 3

10.I Methods of authenticity testing The compositional requirements under Honey Directive are more extensive than those of many other products. Limits are set for apparent reducing sugars, sucrose, water, ash, insoluble solids, diastase number and hydroxymethylfurfurlal and acidity. This seems to reflect an intention to ensure that the honey sold is not adulterated. However more highly sophisticated methods are needed as the cases occurred in which although the sample fulfill the Directive criteria they were known to be subjected to adulteration. Stable Isotope Ratio MS The carbon stable isotope ratio test is well established for detecting the presence of cane or corn syrup. Honey can be adulterated by foreign sugars for cost saving reasons. Such adulterations are easy to implement. Often starch hydrolizates, whose water content is adjusted to a viscosity similar to honey, are used. With the help of 13C isotope ratio mass spectrometry (IRMS), which is

39

established as AOAC Official Method 988.12 , honey blends containing C4 sugar products can be detected. Bees usually use C3 plants for honey production. Because the natural 13C/12C isotope ratios of C3 and C4 sugars are different , sugar admixtures of C4 plants to honeys can be detected when compared. Sugars of C3 plants can only be detected in large admixtures because the nectar sources for the bees belong to the same class of plants.

• C3 sugar Syrups –nectar producing plants, also includes sugar beet and rice: δ13C= –22 –33 ‰

• C4 Sugar syrups –maize and sugar cane from which invert sugar syrups are produced: δ13C = –10 až –20 ‰

• Honey with δ13C higher than –23,5 ‰ is suspicious from aduleteration • There are some exceptions: some honeys (citrus, acacia) belong to δ13C do transient zone –

23,5 až –21,5 ‰ • Then the determination of the internal standard (soluble protein natural to the honey)

overcomes this difficulty

Fig.: Detection of adulterated honey using EA-IRMS16 Pollen analyses Pollen analyses by microscopy is suitable for the identification of botanical and sometimes although geographical origin (Figure). The development of techniques based on the flavour and flavonoid profiles is promising but much work and databases development needs to me done. Figure: Pollen analyses (zoomed 400x)

40

false acacia common sunflower european daisy

10.II Identification of artificial enzyme addition Natural honey contains several enzymes, which are produced by bees (salivary secretion) and some are found in the nectar or pollen. The most important enzymes are amylases, invertases, glusidases, catalases, fosfatases and other. The activity of diastase (α-, β-, γ-amylase) is the important quality parameter of honey, according to the Directive 2001/110/CE the diastase activity (diastase number) must not be less than or equal to 8, for some kinds of honey also higher or equal to 3 (in these cases the HMF must not be higher than 15 mg/kg). Diastase is used as a marker to evaluate the freshness or the heat damage of honey. When honey is adulterated by addition of inverted sucrose or hydrolysed starch namely high fructose corn syrup (HFCS), than such dilution of honey leads to the reduction of diastase number. Such adulteration can be masked by addition of foreign amylases, e.g. bakery mould amylases. The objective of this short communication is to evaluate the factors which are affecting the results of diastase number determination. To detect the addition of foreign amylase the comparison of diastase number for different substrates can be used. In Figure XX there is the comparison of diastase activity determined by Schade and Phadebas assays for the one honey sample spiked with defined amounts of bakery mold amylase (Aspergillus oryzae, VERON® AX, AB Enzymes GmbH, Germany). With higher portions of added enzyme, the results of Schade test were more different from those obtained by Phadebas procedure. In our experiment the starch used for the Schade test probably matched more with substrate specificity of the added mould amylase comparing with substrate in Phadebas tablets. We used the described results to eliminate suspect honey samples and the falsification of those samples was confirmed by the analyses of the other markers, such as sucrose content, 5-furan-2-carbaldehyde (hydroxymethylfurfural) and minor oligosaccharides profiles. Fig.: The comparison of diastase activity determined (DN) by Schade and Phadebas procedure for the one honey sample spiked with defined amount of bakery mold amylase

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12 Eggs and egg products Bird eggs are a common food and one of the most versatile ingredients used in cooking. They are important in many branches of the modern food industry. The most commonly used bird eggs are those from the chicken. Duck and goose eggs, and smaller eggs such as quail eggs are occasionally used as a gourmet ingredient, as are the largest bird eggs, from ostriches. The eggs supply all essential amino acids for humans and provide several vitamins and minerals, including vitamin A, riboflavin, folic acid, vitamin B6, vitamin B12, choline, iron, calcium, phosphorus and potassium. They are also an inexpensive single-food source of protein. All of the egg's vitamin A, D and E is in the egg yolk. The egg is one of the few foods that naturally contain Vitamin D. A large egg yolk contains approximately 60 Calories (250 kilojoules); the egg white contains about 15 Calories (60 kilojoules). A large yolk contains more than two-thirds of the recommended daily intake of 300 mg of cholesterol (although one study indicates that the human body may not absorb much cholesterol from eggs). The yolk makes up about 33% of the liquid weight of the egg. It contains all of the fat, slightly less than half of the protein, and most of the other nutrients. The main cases of the adulteration are:

• Wrong labeling of eggs ( fresh eggs, preserved eggs, different species) • Undeclared technology used • Lowering the egg solids content (dilution, additives addition) in egg based products

12.I The quality of technological liquid egg yolks The composition of egg yolk samples was rather variable and generally lower than that mentioned in the literature. The concentration of phosphorus varied from 5439 to 3138 (average 3939) mg kg-1, of fat from 31.6 to 19.1 (average 22.4) %, of cholesterol from 17406 to 10411 (average 14164) mg kg-1 for all 11 unsweetened samples of yolks. To confirm the obtained results, subsequent analysis of dry matter (varied from 51.6 to 34.0%, average value 41.2%) and lysozyme (varied from 1487 to 100 mg kg-1, average value 724 mg kg-1) content were done. We estimated the real content of clear egg yolk matter as the average of phosphorus, fat, cholesterol and dry matter content (egg yolk markers) and lysozyme content (egg white marker). The correlation between the two mentioned ways of calculation was high enough (R2= 0.93), also correlation between the most easiest and inexpensive method, dry matter determination, and the other measured parameters was rather good (R2 varied from 0.72 to 0.97) so the method seems to be suitable for the fast checking of quality control of technological yolks. To estimate the egg yolk content, the obtained results were recalculated according to the tabulated values for single parameters . Samples no. 1 and 2 represent the samples fully separated, clear yolk and 90% yolk, respectively and the calculated egg yolk content corresponds to the tabulated value. Samples no. 3 to 11 are so-called ”technological yolks” (yolk obtained by industrial separators) and their real content of yolk varies from 64 to 95%. The last three samples (no. 12, 13, 14) contained (due to high sucrose concentration) only from 36 to 42% of yolks.

42

0

20

40

60

80

100

120

1 2 3 4 5 6 7 8 9 10 11 12 13 14Sample No.

Egg

yolk

con

tent

(%)

Estimated according to phosphorus, fat, cholesterol and dry matter contentEstimated according to lysozyme content

Fig.: Estimated content of clear egg yolk matter in analyzed egg yolk.

12.II Egg based products (pasta, egg liquers, mayonnaises) There are numerous published methods for determination (or estimation) of egg content of egg based product. As the basic marker of egg content cholesterol concentration is mentioned both in literature and legislative requirements of several countries. An important disadvantage of cholesterol-based calculations of egg contents is in the high variability of the raw material (from 840 to 1970 and from 170 to 550 mg per 100 g for yolk and edible part of egg, respectively). The egg product should than contain: mayonnaise 168 mg kg-1, egg pasta 197 mg kg-1, home made egg pasta 591 mg kg-1, egg liqueur 1069 mg kg-1 ad liqueurs with added eggs 534 mg kg-1 of cholesterol to fulfill the law requirement. The specification of egg pasta abroad is different, instead of required number of egg pieces per kg of flour; weight of egg solid or directly a minimal content of cholesterol is given. In USA Food Standard Regulations set a minimum of 5.5% by weight of egg solids or egg yolk in the total solids of egg noodle products. A minimum cholesterol content 198 mg 100 g-1 has been reported for noodles containing 5.56% yolk solids Argentine Food Code requires egg pasta to contain two egg yolks per kg of flour, semolina, or their mix and minimally 0.4 g cholesterol per 100 g of dry substance. EU regulations do not specify the minimum amount of eggs in egg products, but national legislations do, e.g. Italy set a minimum of 4 eggs (200 g) per kg of flour. Based on the specific composition of egg it is possible to choose some other characteristic chemical markers of egg solids: • Total phosphorus (mainly in the case of mayonnaises and dressings) or phospolipid (as phosphatidylcholine) content • Total content and composition of fatty acids • Total lipids content • Specific egg proteins to prove the presence of white (ovoalbumin, lysozyme, avidin) and yolk (lipovitelins, phosphatidin) The calculation of egg content in the final product according to selected chemical markers can be, similarly as for cholesterol, rather inaccurate and vary from 50% to 150% of real value. Table Example of Czech legislative requirement for the egg products Product Minimal content

of sucrose (g l-1) Minimal content

of yolks Minimal content of eggs / kg

flour Egg liqueur 150 140 g l-1 * Egg cream 250 140 g l-1 *

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Liqueur with eggs 100 70 g l-1 * Egg pasta * * 2 pc. Pasta, home made * * 6 pc. Egg bakery products * 180 g kg-1 of flour 64 g Mayonnaise * 2 % * *Not relevant

The recent Czech Food Law specifies the presence or minimum concentration of egg or egg yolk content in relevant food products (mayonnaises, egg pastas, egg liqueurs). However, the methods for the determination of egg and/or egg yolk content are not sufficiently specified. Three methods based on determination of cholesterol, lysozyme, fatty acids and lipid content were experimentally validated to evaluate egg content of egg pasta. Concentration of egg solid in the real egg pasta samples was calculated according to 1) average cholesterol content in analysed raw material 2) average lysozyme content in analysed raw material and 3) multiple regression equation for 21 model samples with known egg mass content. To compare the obtained data with the requirements of Czech legislation only 12 from 23 analyzed samples (52%) and 3 from 13 of Czech origin (27%) declared as egg pasta contained two or more eggs per 1 kg of flour. Fig.: Estimated (according to multiple regression of model samples, cholesterol content and lysozyme content) and declared content of eggs in real pasta samples

0

2

4

6

8

10

12

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25

No. of sample

Egg

con

tent

(pc/

kg fl

our)

Multiple regression of model samplesCholesterol contentLysozyme contentDeclared

The presented study deals with the development and evaluation of analytical methods for determination of egg yolk content of egg liqueurs. Due to the high variability of the egg composition and a possible effect of processing to the composition of the product several chemical markers were taken into the consideration: dry matter, phosphorus, fat, cholesterol, fatty acids and lysozyme concentration. The egg yolk content was estimated according to multiple regression analyses of the calibration set (model samples) and to the data obtained for raw materials and described in literature. In compliance with the determined egg yolk content only 6 from 10 analyzed samples of egg liqueurs obtained from the local market met the limit of 140 g l-1 (calculated with the 10% standard deviation error of estimation) required by the recent Czech legislation.

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Fig. Estimated content of egg yolks in real samples of egg liqueurs and creams.

0

20

40

60

80

100

120

140

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1 2 3 4 5 6 7 8 9 10Sample No.

Egg

yolk

con

tent

(g/k

g)

Estimated according to multiple regression equationsEstimated according to phosphorus (corr.), fat, cholesterol and fatty acids

13 Another cases of food adulteration

13.I Adulteration Of Whisky – historical view Genuine Scotch and Irish whisky are produced in accordance with strict manufacturing requirements to guarantee a drink of exceptional and consistent quality. As such they occupy an elite position in the liquor trade and consequently commands high prices. An unscrupulous manufacturers have developed alternative products which are marketed with names indicating a “required” origin, and labelled as whisky. These products, while visually resembling genuine sample, are of inferior quality and lack the flavor components associated with the original. This praxis similar to the situation referred in: Beverages And Their Adulteration Origin, Composition, Manufacture, Natural, Artificial, Fermented, Distilled, Alkaloidal And Fruit Juices written by Harvey W. Wiley in 1919: Adulteration Of Whisky17 The adulteration of distilled liquors in all parts of the world has been continuous and extensive. Perhaps there is no other country where adulteration has reached such proportions as in our own. The discussion of the adulteration of whisky is typical of that which takes place with other distilled liquors, namely, brandy, rum and gin. All of them may be considered as coming under one head, and the statements which are made of whisky may be applied with equal force to the other forms of distilled liquors. The principal types of adulteration are the following: First Selling raw spirits, that is, freshly distilled whiskies, under the guise of age by means of artificial coloring. When whiskies are stored in wood, especially in charred wood, they gradually take on a light amber, deep amber or reddish tint, according to the time of storage and the degree of temperature to which they are subjected. This process can be imitated at once by coloring to the desired tint by means of caramel (burnt sugar). Thus the spirit is mixed with the coloring matter, which gives it the appearance of age and deceives the customer. This method of adulteration may be

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practised in another way, namely, the spirit is stored in a warehouse which is artificially heated. The high temperature causes a more rapid absorption of the color from the wood than otherwise would take place, thus securing in a few months a depth of color which otherwise would have required three or four years to produce. Second Substitution for whisky of a spirit rectified more or less completely and from which, therefore, the substances which give to whisky its character have been entirely or in part removed. This method of adulteration is by far the most extensive of all. A true whisky is a spirit which not only contains ethyl alcohol but a large number of other substances - alcohols, acids, esters, ethers, aldehydes, oils and other flavoring matters derived either directly from the grain, congeneric with alcohol in fermentation, produced by new combinations of ingredients during ageing, or extracted from the wood in which the spirit is aged. All of these ingredients act together to produce the flavor and character of the particular spirit. Substituting for this genuine whisky an article made from rectified spirit saves a great deal of time, expense and loss by storage. The true rectified spirit may be made from any source from which alcohol can be produced, but in point of fact is made principally in the United States from Indian corn. This rectified spirit is known as alcohol, neutral spirit, cologne spirit or velvet spirit, and other similar designations. The procedure is a perfectly simple one. All that is needed to make so-called whisky in this way are mixing vessels and a store of flavors and oils made by a chemist and having more or less resemblance to the natural flavors produced in the making of genuine whisky. Third The third method of adulteration is the refilling of bottles and other packages which have contained genuine whisky with an adulterated article which is still sold under the same name. This has been a very common offense not only against the food law but the revenue laws, which punish with great severity an adulteration of this kind. The latest case of this kind of adulteration to which my attention has been called is a sentence passed on December 4, 1916, against certain offenders by Federal Judge Anderson of Indianapolis. The defendants were indicted for refilling "Bottled in Bond" bottles and selling their contents as "Bottled in Bond Whisky." This was done without destroying or removing the revenue tax stamp by which the "Bottled in Bond Whisky" is identified. Each of the defendants was fined a hundred dollars and costs and sentenced to serve 30 days in jail. The records of the Bureau of Internal Revenue show many offenses of this kind constantly occurring throughout the liquor trade.

13.II Spices and flavourings Flavour is an essential attribute of foods, both native and processed. Since time immemorial, spices and herbs have been added to processed foods to enhance consumer appeal. These additives serve to mask off flavours as well as to import appealing aroma. With the objective of preparing flavour concentrates, extracts, oleoresins and volatile essential oil fractions have been prepared from spices. To import special fruity aromas to certain types of food products, especially ice creams, soft drinks, confections, essential oils of natural origin as well as artificial formulations mimicking these have been in use. Spices, their concentrates, essential oils and flavourants are expensive additives to processed foods and form an important class of food articles of international commerce. The high cost is an inducive to admixing, substitution and adulteration2. The ways of adulteration:

• In the whole spices, adulteration is usually with an inferior variety, an immature dried material, other parts of the same plant, with other plant material of similar appearance and with exhausted spices.

• Spice powders may be admixed with powders of the above adulterants, other plant materials, grain flours, starch and even sawdust.

• The essential oils may be adulterated with nature identical synthetic component(s), essential oils from inferior parts of the plants or cheaper plants with similar properties.

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• Oleoresins and extracts may contain vegetable oils and solvent such as ethanol as extenders and solvent residues.

Table: An overview of the analytical tests for flavorings An example of black and white pepper adulteration2 White and black pepper powder is generally adulterated using starch (from maize and/ or rice) or even corn flour. The piperine content and K: Ca ratio can be used as indices to check this adulteration. In a white pepper/rice starch mixture, an increase in percentage starch decreasesth e piperine content and increases the K:Ca ratio. Mixtures containing maize starch showed decreased piperine content but a less rapid increase in K:Ca ratios. Undried white pepper should contain not less than 3.5% of trans-trans piperine and the ratio of potassium to calcium should not be more than 0.45 on a weight basis. Besides determination of chemical composition microscopic evaluation can be used.

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Table : Influence of exogenous material addition on the composition of white pepper Fig. Black pepper powder a) authentic and b) adulterated by 50% of starch (zoomed 400 x)

Sudan dyes in chilli and red pepper based product Sudan I (1-[(2,4-dimethylphenyl)azo]-2-naphthalenol), Sudan II (1-(phenylazo)-2-naphthol), Sudan III (1-(4-phenylazophenylazo)-2-naphthol) and Sudan IV (o-tolyazo-o-tolyazo-betanaphthol) are an azo-family of synthetic dyes that are widely used for colouring agents such as waxes, floor and shoe polishes. They are categorized as class 3 carcinogens by the International Agency for Research on Cancer (IARC). As a result, Sudan dyes are illegal as additives in foodstuffs destined for human consumption according to both the FSA (Food Standards Agency) and the European Union. Unfortunately, in some countries, these dyes are still being used as additives in some foodstuffs to improve the colour for commercial benefits. Reports have indicated that high amounts of Sudan dyes, at least 1 g L−1, are required to have an impact on visual colour18.

13.III Detection of addition of artificial aroma into wine Wine is very often falsified food commodity. The non-routine, analytical control of wine and wine-based drinks must be addressed to a series of problems very different in nature, e.g. the search for

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additives, particularly stabilizers, to the identification of sugars other than those from grape and to the determination of alcohol derived from sugars other than from grape. The more sophisticate ways of falsification include also the addition of aromas e.g. spices, essential oils, herbal extracts, synthetic linalool or artificial aromas, which are sometimes added to wine to enhance or change the natural aroma of product. Addition of such compounds is illegal in most cases, except the group of “aromatize wines” (vermouth, americano). Recently, the matter of wine adulteration by addition of aroma flavourings has been increasingly discussed among viticultural authorities in the region. Then flavour of wine can be modified by available aroma preparations of unknown content, which are often originally intended for fortification of other beverages than wine. On the market there are available the aroma concentrates with Sauvignon, Chardonnay, Muscatel and Muller Thurgau flavour. Fortification of wines by these concentrates would result in increased or absolutely modified wine variety aroma. The consequence of such adulteration would lead not only in consumer deception but also negative impacted regional high quality wine producers and general Czech wine industry reputation. The aim of the study was to analyze the aroma profiles of Moravian Sauvignon wines and to evaluate the possibilities to detect falsification of those wines by addition of artificial flavourings.

Fig.: Chromatogram of original Sauvignon blanc wine and the same sample spiked with 0.1 mg/l of aroma preparation Aroma Fantasia S (100 ng/l of IBMP added) Methoxypyrazines are principal aroma components responsible for the vegetative and herbaceous green bell-pepper flavour of Sauvignon blanc wines produce in Moravia. Aroma profiles of 8 samples of Moravian Sauvignon wines were analysed, the levels of 3-isobutyl-2-methoxypyrazine varied in the ranges 4.7-17.0 ng/l. The commercial Sauvignon aroma preparation Aroma Fantasia S, which is available in the region was analysed, the product contains the 3-isobutyl-2-methoxypyrazine, and in negligible concentration also anethol and ethylbenzoat. The Moravian Sauvignon blanc wine samples spiked with different amounts of aroma preparation were evaluated by hedonic sensory analysis, to estimate the meaningfulness of such illegal improvement. The most preferred concentration ranged from 5 to 10 ng/l, which are the natural levels of MP in Moravian Sauvignon blanc wines, therefore the addition of aroma at this levels, which could be detectable with difficulties, has no reason. The less sophisticated adulteration of wine, such as production of artificial Sauvignon blanc wine by addition of MP into the less distinctive wines, is easily detectable according to the aroma profile.

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14 Recent issues and projects, practical examples

14.I Recent issues and current projects Under current EU research projects, dozens of public research institutes, universities and private companies are collaborating to develop new methods of identifying evidence of food adulteration. In many cases a combination of methods is needed to prove with legal certainty that EU law providing for food safety or quality has been breached. New methods being developed include DNA sequencing and stable isotope analysis, to identify contaminants or their exact origin. The examples of current research projects outlined here provide for setting up validated databases with reference samples and disseminating these techniques to food standards enforcement authorities19. Five projects selected from the Measurements and Testing generic activity of the Growth Programme of the Fifth Framework Programme for R&TD (FP5): COFAWS - Confirmation of the origin of farmed and wild salmon and other fish (project no. G6RD-2001-00512); GMOchips - New technology in food science facing the multiplicity of new released GMO (project no. G6RD-2000-00419); GLYCEROL - Determination of glycerol in wine - comparison and validation of existing methods (project no. G6RD-2000-00416); SIMBAG-FEED - Screening and identification methods for official control of banned use of antibiotics and growth promoters in feedingstuffs (project no. G6RD-2000-00413); STRATFEED - Strategies and methods to detect and quantify mammalian tissues in feedingstuffs (project no. G6RD-2000-00414. Another EU project TRACE aims to improve the health and well-being of European citizens by delivering improved traceability of food products. The 5 year project sponsored by the European Commission will provide consumers with added confidence in the authenticity of European food through complete traceability along entire fork to farm food chains. TRACE will develop cost effective analytical methods integrated within sector-specific and -generic traceability systems that will enable the determination and the objective verification of the origin of food. It will focus firstly on mineral water, cereals, honey, meat and chicken but will have wider applicability to other commodities. Recent examples of adulteration include20:

• Mogdad coffee, whose seeds have been used as an adulterant for coffee • Roasted chicory roots, whose seeds have been used similarly, starting during the Napoleonic

era in France (and continuing until today as a moderately popular additive for cheaper coffee)

• Roasted ground peas, beans, or wheat, which have been used to adulterate roasted chicory • Diethylene glycol, used by some winemakers to fake sweet wines • Oleomargarine or lard, added to butter • Rapeseed oil, commonly added to sunflower oil and soybean oil, brassicasterol being a

marker of its presence • Rye flour, corn meal or potato starch, used to dilute more expensive flours; alum is also

added to disguise usage of lower-quality flour • Apple jellies, as substitutes for more expensive fruit jellies, with added colorant and

sometimes even specks of wood that simulate strawberry seeds • Artificial colorants, often toxic - e.g., copper, zinc, or indigo-based green dyes added to

absinthe • Sudan I yellow color, added to chili powder, as well as Sudan Red for red color • Water, for diluting milk and beer and hard drinks

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• Low quality black tea, marketed as higher quality tea • Starch, added to sausages • Cutting agents, often used to adulterate (or "cut") illicit drugs - for example, shoe polish in

solid cannabis • Urea, melamine and other non-protein nitrogen sources, added to protein products in order

to inflate crude protein content measurements • Powdered beechnut husk aromatized with cinnamic aldehyde, marketed as powdered

cinnamon. • High fructose corn syrup or cane sugar, used to adulterate honey; C4 sugars serve as

markers, as detected by carbon isotopic signatures • Glutinous rice coloring made of hazardous industrial dyes, as well as tinopal to make rice

noodles whiter (to serve as bleach) • Noodles, meat, fish, tofu preserved with formaldehyde in tropical Asia, to prevent spoilage

from the sun

14.II Practical examples for the evaluation of food authenticity according to provided data

Self control test: 1) Which food can be demanded as adulterated? 2) Name some historical examples of adulteration. 3) Give an example of relevant EU legislative. 4) Which are the characteristic markers of egg content in product? 5) How can be olive oil adulterated? 6) Give a general methodology of authentication. 7) Give at least 3 examples of orange juice (100 % fruit content) adulteration and specify chemical

markers (parameters) of its authenticity. 8) Name the example of toxic adulterant. 9) The cases of milk and dairy product authenticity issues 10) Give the composition criteria for honey EXAMPLE – evaluate the authenticity of apricot jam, calculate the fruit content: Marker Unit Sample Formol number ml 0.1mol NaOH/100 g 18 Malic acid mg/100 g 287 Citric acid mg/100 g 607 Ash g/100 g 0.32 K mg/100 g 146 P mg/100 g 11 Sucrose g/100 g 18.4 Gluctose g/100 g 19.1 Fructose g/100 g 19.1 Sorbitol g/100 g <0.25 Fruit content g/100 g Authors references: Voldřich M., Skálová P., Kvasnička F., Cuhra P., Kubík M., Pyš P. : Authenticity of 100% orange juice in the Czech market in 1996–2001, Czech J. Food Sci. Vol. 20, No. 2: 83–88 Helena Čížková, Michal Voldřich, Ernesto L. Morales, Rudolf Ševčík: Confirmation of Aroma Restoration into the Reconstituted Orange and Apple Juices, Euroanalysis 2009, 6.-10.9 2009, Innsbruck, Austria

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Čížková Helena et al. Authenticity Evaluation of Tea-Based Products.. Czech Journal of Food Science , 2008 , 26 ,. 4 , s. 259-267 . Čížková Helena et al. Differentiation of coffee varieties according to their sterolic profile. Journal of Food and Nutrition research , 2007 , č. 46 , s. 28-34 . Voldřich M., Rajchl A., Čížková H., Cuhra P: Detection of foreign enzyme addition into the adulterated honey, Czech J. Food Sci, Vol. 27, 2009, S280-S282, Special Issue Rajchl, Ales; Cizkova, Helena; Voldrich, Michal; Lukesova, Dobromila; Panovska, Zdenka. Methoxypyrazines in Sauvignon blanc wines, detection of addition of artificial aroma. Czech Journal of Food Sciences (2009), 27(4), 259-266. Cizkova, H.; Sevcik, R.; Rajchl, A.; Voldrich, M. Nutritional quality of commercial fruit baby food. Czech Journal of Food Sciences (2009), 27(Spec. Iss.), S134-S137. Soukupova, V.; Cizkova, H.; Voldrich, M. Evaluation of ketchup authenticity - chemical changes of markers during production and distribution. Czech Journal of Food Sciences (2004), 22(Spec. Iss.), 349-352. References: 1 Food Authenticity - Issues and Methodologies, Ed. M. Lees Eurofins Scientific Nantes, France pp 185-207 ISBN 2-9512051-0-4 CID Imprimerie, 448816 Saint Herblain, France 2 Handbook of Indices of Food Quality and Authenticity, Rekha Singhal , Publisher: CRC; 1997, SBN-10: 1855732998 3 www.historyhome.co.uk/peel/p-health/food.htm 4 A. H. Hassall, Food and its adulterations; comprising the reports of the analytical sanitary commission of 'The Lancet' for the years 1851 to 1854. London: Longman, 1855. 5 http://en.wikipedia.org/wiki/Melamine 6 http://www.eurofins.com/en/our-services/food--feed-testing/authenticity-testing.aspx 7 (http://www.nal.usda.gov/fnic/foodcomp/Data/SR15/sr15.html 8 Siegfried W. Souci • W. Fachmann • Heinrich Kraut: Food Composition and Nutrition Tables, Stuttgart 2000, CRC Press 9 http://www.aijn.org/ 10 http://en.wikipedia.org/wiki/Traceability 11 http://www.trace.eu.org 12 http://ec.europa.eu/agriculture/quality/database/index_en.htm 13 Simon Kellya et al.: Tracing the geographical origin of food: The application of multi-element and multi-isotope analysis, Trends in Food Science & Technology, 16 (12), 2005, 555-567 14 Commission Regulation (EC) No 273/2008 of 5 March 2008 laying down detailed rules for the application of Council Regulation (EC) No 1255/1999 as regards methods for the analysis and quality evaluation of milk and milk products 15 Coffee adulteration and analytical approaches to authentication, C. W. HARRELL and D. R. White, Jr., 2001 IFT Annual Meeting - New Orleans, Louisiana 16 Forensic applications of isotope ratio mass spectrometry—A review, Forensic Science International, Volume 157, Issue 1, Pages 1-22, S. Benson, C. Lennard, P. Maynard, C. Roux 17 http://chestofbooks.com/food/beverages/Adulteration-Origin/index.html 18 Determining the adulteration of spices with Sudan I-II-II-IV dyes by UV–visible spectroscopy and multivariate classification techniques, Talanta, Volume 79, Issue 3, 15 August 2009, Pages 887-892, Carolina V. Di Anibal, Marta Odena, Itziar Ruisánchez, M. Pilar Callao 19 http://ec.europa.eu/research/growth/gcc/projects/food-fraud.html 20 http://en.wikipedia.org/wiki/Adulteration#In_food_and_beverages