Food hygiene and control

SITHARA V . P II nd semester Msc microbiology

Food hygiene• Food is a potential source of infection and is liable

to contamination by microbes, at any point during its journey from the producer to the consumer.

• Food hygiene may be defined as the sanitary science which aims to produce food which is safe for the consumer and of good keeping quality.

• It covers a wide field and includes the rearing, feeding, marketing and slaughter of animals as well as the sanitation procedures designed to prevent bacteria of human origin reaching food stuff.

•Food hygiene in its widest sense, implies hygiene in the production, handling, distribution and serving.

•WHO (1984) has defined food hygiene as all conditions and measures that are necessary during production, processing, storage, distribution and preparation of food to ensure that it is safe, wholesome and fit for human consumption.

•The primary aim of food hygiene is to prevent food poisoning and other food borne illness.

Food control•The objective of control has three aspects•1. economic•2. aesthetic•3.public health

Different branches of food hygiene include:•Milk hygiene•Meat hygiene•Fish hygiene•Egg hygiene•Hygiene of vegetables and fruits•Food handlers hygiene•Sanitation of eating place.

Milk hygiene•Milk is an efficient vehicle for a great

variety of disease agents.•Milk get contaminated by various sources

like udder, utensils, personal hygiene of the handlers, storage environment, water etc.

Off Milk

Milk borne diseases•A joint FAO\WHO expert

committee(1970) on milk hygiene classified milk borne disease as under- infections of animals that can be transmitted to man.

•Tuberculosis•Streptococcal infections•Anthrax

Infections primary to man that can be transmitted through milk•Typhoid and paratyphoid fevers•Cholera•Enteropathogenic Escherichia coli.

Clean and safe milk•First essential is a healthy and clean

animal.

•Secondly, the premises where the animal is housed and milked should be sanitary.

•Milk vessels must be sterile and kept covered.

•Water supply should be bacteriologically safe.

•Milk handlers must be free from communicable diseases.

•Milk should be cooled immediately to 10o c after it is drawn to retard bacterial growth.

Methylene blue reduction test•It is indirect method for detection of

microorganisms in milk.•Test is carried out on the milk accepted

for pasteurization.•Definite quantity of methylene blue is

added to 10 ml of milk and sample is held at a uniform temperature of 37 deg.c until the blue colour is disappeared.

•This test serves as confirmation of heavy contamination and compared with direct counts of bacteria , it saves time and money.

Methods of pasteurization •Holder (VAT) method – in this process

milk is kept at 63-66 0 c for at least 30 min and cooled to 5 0 c .

•HTST method –milk is rapidly heated to a temperature of nearly 72 0 c is held at that temperature for not less than 15 sec and is then rapidly cooled to 4 0 c .

Meat hygiene•The diseases which may be transmitted by

eating unwholesome meat are:•Tapeworm infestations•Tinea saginata•Trichinella spiralis•Fasciola hepatica

Microbial infections•Actinomycosis•Tuberculosis•Food poisoning

Meat inspection•Animal intended for slaughter are

subjected to proper ante mortem and post mortem inspection by qualified veterinary staff.

•Meat inspection is a very important process before being accepted or rejected.

Anti mortem inspectionThe term ante -mortem ‘’before death’’

• Is the inspection of live animals and birds prior to being slaughtered.

OBJECTIVES• To screen all animals destined to slaughter• To ensure that animals are properly rested

and that proper clinical information ,which will assist in the disease diagnosis and judgement is obtained.

• To identify sick animals.

Principle causesAntemortem rejection –it is based on•Exhaustion•Emaciation•Pregnancy•Sheep pox•Brucellosis•Diarrhoea

Postmortem inspection• Routine postmortem examination of a carcass

should be carried out as soon as possible after the completion of dressing

• It helps to detect abnormalities, so that products only conditionally fit for human consumption are passed as food.

Signs of generalized disease are• Inflammation of joints• Lesions in different organs

Postmortem rejection –it is based on• Cysticercus bovis, liver fluke, abscesses,

Sarcocystis sps, hydatidosis, septicaemia, parasitic and nodular infections of liver and lungs, tuberculosis, Cysticercus cellulosae.

Good meat qualitiesIt should be neither pale pink nor

a deep purple tint.

Firm

Elastic to touch

Should not be slimy

Have an agreable odour.

Slaughter house hygiene•Hygiene of slaughter house is important

to prevent contamination of meat during the process of dressing.

•There is a model public health act (1955) in India, which standardizes on the location ,structure , disposal of wastes, water supply ,examination of animals , storage of meat , transportation of meat and miscellaneous other activities connected with meat processing.

Slaughter Houses Location: Preferably away from

residential areas.

Structure: Floors and walls up to 3 feet should be impervious and easy to clean.

Disposal of wastes: Blood, offal, etc…

should not be discharged into public sewers but should be collected separately.

Water Supply: should be independent, adequate and continuous.

Examination of animals: Antemortem and postmortem examination to be arranged. Animals

or meat found unfit for human consumption should be destroyed or denatured.

Miscellaneous: animals other than those to be slaughtered should not be allowed

inside the shed. Storage of meat: Meat should be stored in fly-proof and rat-proof rooms; for overnight

storage, the temperature of the room shall be maintained below 5°C.

Transportation of meat: Meat shall be transported in fly-proof covered vans.

Fish hygiene

•Fish deteriorates or loses its freshness because of autolysis which sets in after death and because of the bacteria with which they become infected.

• Stale fish should be condemned. • The signs of fresh fish: 1) It is in a state of stiffness or rigor

mortis2) The gills are a bright red 3) The eyes are clear and prominent

Tinned fish hygieneInspection of tinned fish-•The tin must be new and clean without

leakages or rusting.•There should be no evidence of having

been tampered with such as sealed openings.

•On opening the tin, the contents should not blown out which indicates decomposition.

EGG HYGIENE•Although the majority of freshly laid eggs

are sterile inside, the shells become contaminated by faecal matter from the hen.

• Microorganisms including pathogenic Salmonella can penetrate a cracked shell and enter the egg yolk leading to spoilage .

•Eggs can also be pasteurized to increase the shelf life.

FRUITS AND VEGETABLES HYGIENE•Vegetables & fruits host many

pathogens like bacteria , fungal ,protozoan which can enter the plant material during or after harvesting.

•Generally proper washing and sanitization are employed to increase shelf life and product safety.

•Freshly harvested products are routinely washed to remove soils ,pesticide residues ,insects , plant debris , and microbes.

Hygiene for Food Handlers•Food sanitation rests directly upon the

state of personal hygiene and habits of the person working in food industries.

•The infections which are likely to be

transmitted by the food handlers are diarrhoea, dysenteries, typhoid and para-typhoid fevers, entero-viruses, viral hepatitis, protozoa cysts, eggs of helminthes, streptococcal and staphylococcal infections and salmonellosis.

Rules for food handling• Medical examination carried out of all food

handlers at the time of employment. Any person with a history of typhoid fever, diphtheria, chronic dysentery, tuberculosis or any other communicable disease should not be employed.

• Persons with wounds, skin infections should not be permitted to handle food or utensils.

• The day to day health appraisal of the food handlers is also equally important; those who are ill should be excluded from food handling

•Any illness which occurs in a food handler's family should at once be notified

•Education of food handlers in matters of personal hygiene, food handling, utensils, dishwashing, and insect and rodent control is the best means of promoting food hygiene.

• Personnel hygiene to be promoted:

(a) Hands: The hands should be clean at all times. scrubbed and washed with soap and water immediately after visiting a lavatory. nails to be kept trimmed and free from dirt.

(b) Hair – to provide covering to the head

(c) Overalls: Clean white overalls to be worn by all food handlers.

(d) Habits: Coughing and sneezing in the

vicinity of food, licking the fingers before picking up an article of food, smoking on food premises are to be avoided.

SANITATION OF EATING PLACES•It is a challenging problem in India.

•There some minimum standards suggested for restaurants and eating places in India under the MODEL PUBLIC HEALTH ACT, govt.of India(1955).

•Location: Shall not be near filth or open drain, stable, manure pit and other sources of nuisances.

• Floors: To be higher than the adjoining land, made with impervious material and easy to keep clean.

• Rooms: (a) Rooms where meals are served shall not

be less than 100 sq. feet and shall provide accommodation for a maximum of 10 persons.

(b) Walls up to 3 feet should be smooth,

corners to be rounded; should be impervious and easily washable

c) Lighting and ventilation – ample natural lighting

facilities aided by artificial lighting with good

circulation of air are necessary.

(4) Kitchen: It should be ample floor space , window opening ,

proper flooring and ventilation.

(5) Storage of cooked food:

Separate room to be provided. For long storage, control of temperature is necessary.

(6) Storage of uncooked foodstuffs.

Perishable and non-perishable articles to be kept separately in rat-proof and vermin-proof space; for storage of perishable articles temperature control should be adopted.

Flies on the Food

•Furniture: Should be reasonably strong and easy to

keep clean and dry. (8) Disposal of refuse: To be collected in

covered, impervious bins and disposed of twice a day.

(9) Water supply: To be an independent source, adequate, continuous and safe.

(10) Washing facilities: To be provided. Cleaning of utensils and crockery to be done in hot water and followed by disinfection

ADULTERATION OF FOODS• Adulteration of foods consists of a large

number of practices - mixing substitution, abstraction, concealing the quality, putting up decomposed foods for sale, misbranding or giving labels and addition of poisons.

• Some forms of adulteration are injurious to health, eg., adulteration of mustard oil with argemone oil. But for the most part food adulteration has an economic rather than a sanitary significance eg., addition of water to milk

Food control•“….the regulatory activity enforce by

national or local authorities to provide consumer protection and ensure that all foods during

production, handling, storage, processing, and distribution are safe, wholesome and fit for human consumption; conform to safety and

quality requirements; and are honestly and accurately labeled as prescribed by law”.

Food control administration•This varies from country to country.

•The central ,state and local bodies are responsible to enact laws and implementations.

•There should be laws to control raw materials , processing foods , preservation methods and control of milk or meat hygiene , etc..

Laws relating to food control in India are• The prevention of food adulteration act

1954,amended in 1976,1986.• Prevention of food adulteration rules,1955.• Indian penal code 1860 as amended.• Cantonment act 1924.• The Bombay municipal corporation act ,1888.• The Bombay provincial municipal corporations

act,1949.• The Maharashtra zilla parishads and panchayat

samiti’s act ,1961.• Tamil nadu public health act,1939 and so on for

each state.

PROVISIONS OF THE ORIGINAL PFA ACT,19541) Definition of food.2) Definition of food adulteration or

misbranding.3) Appointment of an advisory committee

called the central committee for food standards (CCFC).

4) Establishment of the central food laboratory ,Calcutta, in 1955 and later in each state to give a final option in cases challenged in the court of law.

5) Restriction on imports of adulterated or misbranded foods or other spoilt foods.

6) Power of the state governments to appoint public analysts or food inspectors.

7) Procedure for food inspectors in drawing and dispatching sample of food to laboratory.

8) Powers to the central govt for defining the standards of quality ,control , over production , distribution ,sales , packing , labelling ,etc.

9) Penal provisions provided a maximum imprisonment of one year or a minimum fine of Rs.2000/- in the first instance and imprisonment of 2 years on the second offence and in the third instance, imprisonment up to 4 years.

Food standards•Codex alimentarius is a collection of

international food standards prepared by codex alimentarius commission (organ of FAO/WHO food standard programme ).

Indian standards are based on this .

• PFA standards based on PFA act 1954 “central committee of food standards” revised periodically to get minimum level of quality of food stuff attainable under Indian conditions.

•AGMARK (Agricultural Marketing , HO , Faridabad) standards set by the director of marketing and inspection, govt of India.

•The AGMARK gives consumers the assurance of quality in accordance with standards laid down.

HACCP

• H azard A nalysis and C ritical C ontrol P oints• The HACCP system, which is science based and

systematic, identifies specific hazards and measures for their control to ensure the safety of food.

• HACCP is a tool to assess hazards and establish control systems that focus on prevention rather than relying mainly on end-product testing.

• Any HACCP system is capable of accommodating change, such as advances in equipment design, processing procedures or technological developments.

• The successful application of HACCP requires the full commitment and involvement of management and the work force.

• It also requires a multidisciplinary approach; this multidisciplinary approach should include, when appropriate, expertise in agronomy, veterinary health, production, microbiology, medicine, public health, food technology, environmental health, chemistry and engineering, according to the particular study.

• The application of HACCP is compatible with the implementation of quality management systems, such as the ISO 9000 series, and is the system of choice in the management of food safety within such systems.

HACCP’S SEVEN PRINCIPLES FOR FOOD SAFETY

1. Analyze Hazards2. Identify Critical Control Points3. Establish Critical Limits for each Critical

Control Point4. Establish Monitoring Procedures5. Establish Corrective Actions6. Establish Verification Activities7. Establish Records and Documentation

Principal food control options availableApproach Components Education and training

Develop an understanding of food hazards.Develop an appreciation of personal hygiene ,sanitation ,and food hygiene.Develop an understanding of microbial contaminants and control measures.

Introduce factors affecting microbial growth and survival.

Inspection of processing facilities ,food handling operations ,warehouses etc..

Monitor adherance to a recommended or required food handling practice.Follow a recommended or required guideline such as good manufacturing practice(GMP).Cite violations or make recommendations for improving performance.

Microbiological surveys and testing of product

•Sample and analyze ingredients, components , and finished product.•Monitor for pathogens ,indicators, total numbers ,etc.•Compare to a standard ,a guideline , a defect action level ,etc. and advice or regulate accordingly.

“New approaches”

•Combinations of the above to improve upon the prevention of food borne diseases•HACCP concept.

Ramesh , Vijaya . FOOD MICROBIOLOGY.mjp publishication.pp:521-527.

Frazier,WC.,Westhoff. FOODMICROBIOLOGY. 4ed.

REFERENCES

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