five risk factors preventing foodborne illness through appropriate control measures

Five Risk Factors

Preventing foodborne illness through appropriate control measures

C 5.01 -- Five Risk Factors

Five Risk Factors1. Food from unsafe source – using food from home or

unlicensed providers. 2. Inadequate cooking – not heating food to temperatures

that kill pathogens. 3. Improper holding temperature – holding food at an

unsafe temperature for more than four hours.4. Contaminated equipment – using unclean utensils or

equipment when preparing food.5. Poor personal hygiene – unsanitary habits by workers,

such as not washing hands before handling food or after using the bathroom.


Factors associated with reported cases of foodborne illness

63% inadequate cooling and cold-holding temperatures

29% preparing food ahead of planned service 27% inadequate hot-holding temperatures 26% poor personal hygiene/infected persons 25% inadequate reheating 9% inadequate cleaning of equipment


7% use of leftovers 6% cross-contamination 5% inadequate cooking or heat processing 4% containers adding toxic chemicals 2% contaminated raw ingredients 2% intentional chemical additives 1% incidental chemical additives 1% unsafe source


Control Risk Factors A food safety plan should control for the five

risk factors. Control measures must be specific to the

operation. Foodborne illness is nearly 100% preventable

if appropriate control measures are implemented.

C 5.01 -- Microbiology

Microorganisms


Microbiology

Microorganisms are everywhere.

Microbiology is the study of microorganisms—living organisms too small to be seen by the naked eye without magnification.


Three Roles of Microorganisms

Pathogens -- cause foodborne illness. Spoilers -- cause food to spoil and decrease

its shelf-life. Beneficial -- used for food fermentation and

are naturally present in and on the body.


Contaminated Food Microorganisms can contaminate

any food: naturally or through improper food handling

Contaminated food can cause foodborne illness or food spoilage.

Measures must be implemented to control for:

Food safety – preventing foodborne illness and

Food quality – maximizing shelf-life


PathogensFoodborne illness

An illness caused by eating contaminated foods or beverages.

Foodborne illness outbreak the occurrence of two or more

cases of a similar illness resulting from eating a common food.

Each year there are: 76 million cases of foodborne

illness 323,914 hospitalizations 5,194 deaths


Spoilers

Cause the deterioration of food, such as sour milk or lunch meat turning slimy.

Eating spoiled food does not usually cause illness.

Food spoils because of microbial growth or enzymatic activity.


Beneficial

Beneficial microorganisms are not contaminants – they are naturally present or are intentionally added to foods.

Primary purposes: Health benefits – naturally

present on skin and in the intestinal tract.

New food products – use for food fermentation to create new products.

Yogurt

Sour doughculture


Five Major Groups of Microorganisms

1. Bacteria

2. Viruses

3. Parasites

4. Mold

5. Yeast


Bacteria Basics

Invisible to the naked eye. Pathogens, spoilers, and

beneficial. Grow in food. Some produce spores. Some produce toxins. Not necessarily destroyed by

freezing or cooking. Bacillus cereus


Virus Basics Invisible to the naked eye. Pathogens -- not spoilers or beneficial. Do not grow in food; use food as a

vehicle to get from one person to another

Can contaminate any food Cause most foodborne illnesses in the

U.S. Usually destroyed by cooking but not

freezing.

Norovirus


Parasite Basics Some are visible to the naked eye Pathogens – not spoilers or

beneficial. Do not grow in food Found naturally in many animals

pigs cats rodents, and Seafood

Destroyed by proper freezing and cooking. Anisakis simplex


Mold Basics Visible to the naked eye. While most spoil food, some are

pathogenic and some beneficial. Some form toxins that can cause

illness. Grow in a wide range of foods –

high acid, low moisture. Requires air to grow Freezing does not destroy.


Yeast Basics Visible to the naked eye. Spoilers and beneficial but not

pathogenic. Grow in a wide range of foods –

high acid, low moisture. Produce a smell, bubbling, or a

taste of alcohol when food spoils Easily destroyed by proper

processing.

Control MeasuresControl Measures

Control MeasuresControl Measures

Focus on safety and quality Food safety control measures -- prevent foodborne

illness. Food quality control measures -- maximize shelf-

life, slow spoilage, or produce a new product. Processors use a combination of controls

One-control system can be harsh making food unacceptable to the consumer.

Multiple controls is called the hurdle concept and is commonly used.

C 5.01 -- Control Measures

Hurdle ConceptHurdle Concept

Food processors use a combination of control measures called hurdle concept.

The three primary control measures are:1. Controlling water activity and/or pH values of the

food.2. Adding chemicals, such as additives or substances

like salt, directly to the food.3. Adjusting the atmosphere surrounding the food

using special packaging methods.


1a -- Controlling Water 1a -- Controlling Water ActivityActivity

Water activity (Aw) Minimum, optimum, and maximum values Yeasts and mold grow at a lower water

activity than do bacteria. 0.85 safe cutoff for pathogen growth

Based on minimum water activity needed for S. aureus toxin production.


Water activity and foodsWater activity and foods

Above 0.85 Moist foods Refrigeration or another barrier to control pathogen growth

0.60 and 0.85 Intermediate moisture foods

No refrigeration, short shelf-life because spoilage by yeast and mold

Below 0.60 Low moisture foods

Extended shelf-life without refrigeration


Controlling water activityControlling water activity

Method Foods

Hot air drying Solid foods like vegetables, fruit, and fish

Spray drying Liquids and semi-liquids like milk

Vacuum drying Liquids like juice

Freeze drying Variety of foods

Adding salt or sugar Soy sauce, jams, salted fish


1b -- Controlling pH1b -- Controlling pH

Minimum, optimum, and maximum pH values for microbial growth Yeasts and mold grow at low pH.

Pathogenic bacteria do not grow at 4.6 or below. pH controls growth and is not a method to

kill pathogens.


Ways to Control pHWays to Control pH

Acidification direct addition of acid to a low-acid food Use organic acids, acetic, lactic, or citric or add high-acid

food to mixture Direct – predetermined amounts of acids added to

individual finished product Bath – acid and food combined in large batches and

allowed to equilibrate. Fermentation

Lactic acid bacteria produces lactic acid.


Measuring pHMeasuring pH pH meter Digital method but expensive Easy, the MOST accurate, and sanitary

Indicator solutions Organic dyes used with dropper Solution turns pink or red in acid; green or blue in base Neutral solution may turn lilac and might be difficult to read Not totally accurate

Indicator paper Used by dipping Turns yellow to red in acids; turns green or blue in bases Easy but not completely accurate

Titration Add base with know ph to an acid Uses burette Difficult to calculate math so recommended for those with chemistry knowledge


2 -- Adding Chemicals2 -- Adding Chemicals

Preservation method might not prevent growth of all microorganisms.

Add chemical preservatives, such as: sorbates benzoates sulfites nitrites antibiotics


How Chemicals Function Denature proteins. Inhibit enzymes. Alter or destroy cell walls. Alter or destroy cell membranes.

Common Chemical Common Chemical PreservativesPreservatives

Preservative Mechanism

Benzoates Inhibit yeast or mold

Sorbates Inhibit mold

Propionic acid Inhibit mold

Sulfites Antioxidant and antimicrobial

Nitrites Inhibit C. botulinum

Salt Inhibit pathogens, especially C. botulinum

Antibiotics -- nisin Antimicrobial in cheese


Regulating PreservativesRegulating Preservatives

Chemical preservatives are food additives. Approved uses and use levels in FDA’s Food

Additive Status List. Addressed through product formulation.

Processor must carefully control the quantity of food additive for each batch.

Processing conditions must be scientifically established and followed


3 -- Adjusting the 3 -- Adjusting the AtmosphereAtmosphere

Packaging does not control the growth of pathogens, it is limited to the control of spoilage microorganisms.

Two functions: Prevents contamination of the food and/or Extends the effectiveness of food preservation

methods.


Types of PackagingTypes of Packaging

Reduced Oxygen Packaging (ROP) – prevents growth of microorganisms to extend shelf-life Vacuum Packaging – air mechanically removed from the

package before sealing Modified Atmosphere Packaging – flush with nitrogen,

carbon dioxide, and/or oxygen before sealing. Controlled Atmosphere Packaging – retain atmosphere

throughout shelf-life using an oxygen scavenger in packaging.


Packaging Packaging –– Key Key ConcernsConcerns

If ROP used, must have barrier to C. botulinum. Barriers include:

Water activity below 0.93 with refrigeration pH below 4.6; salt above 10% High levels of competing microorganisms Thermal processing in final container Freezing with frozen storage and distribution


TCS FoodsTCS Foods

DefinitionDefinition

Potentially hazardous food is typically neutral or slightly acidic (low acid),

moist, and contains protein. requires temperature control to prevent bacteria

growth of bacteria. Time-Temperature Control for Safety

(TCS) is the correct name in the current ServSafe® Essestials.

C 5.01 -- Potentially Hazardous Food

Conditions for Bacterial Conditions for Bacterial GrowthGrowth

In the retail food industry, conditions of bacterial growth called FAT-TOM: F -- Food A -- Acid T -- Temperature T -- Time O -- Oxygen M -- Moisture


F = FoodF = Food

Food that meets the definition of TCS. Bacteria grow in these foods but other

pathogenic microorganisms do not, such as viruses and parasites.


A = AcidityA = Acidity

pH is degree of acidity (amount of acid) or alkalinity (amount of base) of a substance.

Measured on scale from 0 to 14. pH of 7.0 is exactly neutral--neither acid nor alkaline. pH below 7.0 is acidic pH above 7.0 is alkaline.

Bacteria grow best at neutral or slightly acidic pH levels, especially between 6.6 and 7.5.


T = TemperatureT = Temperature

All bacteria grow by cell division (also known as doubling).

When a potentially hazardous food is in the temperature danger zone (between 41oF and 135oF), pathogens multiply.

Pathogens do not grow at the same rate across the danger zone. 60oF – double every two hours. 70oF – double every sixty minutes. 90oF – double every 30 minutes.


T = TimeT = Time

The longer TCS is in the temperature danger zone, the more pathogenic bacteria will grow.

Limit time in the temperature danger zone to no more than four hours.


O = OxygenO = Oxygen

Aerobic Require oxygen to grow

Anaerobic Grow only in the absence of oxygen

Facultative Can grow whether the atmosphere has oxygen or

note. Microaerophilic

Grow only in reduced oxygen environments


M = MoistureM = Moisture

Water activity is a measure of the amount of water available for bacterial growth.

Pathogenic bacteria can grow in foods that have a water activity of 0.85 or higher – moist foods.

0.85 is based on the minimum water activity for Staphylococcus aureus toxin production.


Definition and Types

Fermentation In practice, fermentation is an art. Encourage growth of the right

microorganisms and discourage growth of microorganisms that cause spoilage.

Accomplished by adding salt or a starter culture to the food, or in some cases slightly acidifying it.

C-5.02 -- Fermentation

What is it?

Enzymatically controlled change in food

Caused by microbes Changes caused by

Break down of components Glucose Pyruvate acid or alcohol + CO2

Release of by-products


By-Products -- Changes and Advantages

Changes: Color Texture Flavor Aroma pH

Advantages: New products Increases shelf-life Increases variety of food

products available


Starter Culture A starter culture can be:

Yeast, Bacteria, or Mold

Influence quality characteristics; such as texture, moisture content, no pathogens and their

toxins, and taste.


Uses in the food industry

End product

Raw ingredient

Starter culture

Beer Barley and hops

Yeast

Bread Sugar in dough

Yeast

Yogurt Milk Bacteria

Cheese Milk Bacteria

Pickles Cucumber Bacteria

Vinegar Cider, wine BacteriaC-5.02 -- Fermentation

Yeast Fermentation

Saccharomyces cerevisiae Uses sugar as fuel A fungus

Food products Yeast breads Alcoholic

beverages


Bacterial Fermentation

Lactic Acid Pickled vegetables (cabbage,

cucumbers, olives) Semi dry and dry sausages Cultured dairy products

Acetic Acid Two step process (yeast creates

wine) Acetic acid bacteria creates

vinegar


Mold Fermentation

Antibiotics Flavor compounds Enzymes Two-step fermentation

with mold includes chocolate and cheeses

Products: Tempeh Soy sauce


Tempeh

Soy sauce

Industrial Fermentation Important process in industry

Food Pharmaceuticals and Biotechnology Sewage

Breakdown organic substances and re-assembly into other substances.

C-5.02 -- Industrial Fermentation

Food Applications

Bread Wine Cheese Curds Pickles Fermented sausages


Pharmaceutical and Biotechnology

Microbial cells or biomass -- Bakers yeast, lactic acid bacillus, Bacillus sp.

Microbial enzymes -- Examples include catalase, amylase, protease

Microbial metabolites -- Ethanol, citric acids, vitamins, lysine

Recombinant products -- Insulin, interferon Biotransformations -- Phenyl acetyl carbinol


Sewage Disposal Sewage digested by enzymes from bacteria Solids broken down into harmless, soluble

substances and CO2

Liquids disinfected to remove pathogens Digested sludge – dried and used as fertilizer. Gas by-products (methane) – biogas
