Food Safety

Introduction

Food safety has become an issue of special importance for the retail food industry. There are many opportunities for food to be contaminated between production and consumption. Food can be contaminated at the farm, ranch, orchard, or in the sea. Food also can be contaminated at food processing plants and during transport to food establishments. Finally, food can be contaminated during the last stages of production, at retail establishments, and by consumenrs in their homes. Even when food is purchased from inspected and approved sources, ingredients may be contaminated when they arrive at the food establishment. It is important to know how to handle these ingredients safely and how to prepare food in such manner that reduces the risk of contaminated food being served.

The Food and Drug Administration (FDA) is one of the federal agencies that is responsible for protecting our food supply. The Agency recognizes the importance of proper food handling in retail food establishments. Food safety in retail food establishments begins with managers who are knowledgeable about food hazards and who are committed to implementing proper food handling practices in their facility. It continues with properly trained food workers who understands the essentials of food safety and sanitation and who will not take shortcuts when it comes to food safety.

Foodborne Illness

Foodborne illness is any illness caused by the consumption of a contaminated food. Symptoms of foodborne illness generally include nausea, vomiting, diarrhea, headache, and fever. Experts estimate that approximately 25 to 81 million cases of illness and over 10,000 deaths can be attribute to foodborne illness every year. When a living , disease-causing microorganism is eaten along with a food, it can cause a foodborne infection. After ingestion, the organism burrows into the lining of the victim's digestive tract and begins to grow in number. This can lead to the common symptoms of foodbrone illness such as diarrhea. Bacteria, virues, and parasites are examples of microorganisms that can cause infection. A common type of foodborne infection is Salmonellosis. This is caused by Salmonella bacteria that are frequently found in poultry and eggs.

An intoxication is caused when a living organism multiplies in or on a food and produces a chemical waste or toxin. If the food containing the toxin is eaten, the toxin causes an illness. Typically called food poisoning, common examples of food intoxications are Clostridium botulinum and Staphylococcus aureus. An intoxication may also occur when an individual consumes food that contains manmade chemicals such as cleaning agents or pesticides.

A toxin-mediated infection is caused when a living organism is consumed with food (as in the case of an infection). Once the organism is inside the human body it produces a toxin that causes the illness. Toxin-mediated infection is different from an intoxication because the toxin is produced inside the human body. An example of an organism that causes this type of illness is Clostridium perfringens.

Under the right circumstances, anyone can become ill from eating contaminated foods. In most cases, healthy adults will have flu-like symptoms and recover in a few days. However, the risks and dangers associated with foodborne illness are much greater for certain members of the population such as infants and young children, the elderly, pregnant women, and those with suppressed immune systems as occurss with AIDS. For these individuals, the symptoms and duration of foodborne illness can be much more severe, even life threatening.

Foodborne Hazards

A foodborne hazard refers to a biological, chemical, or physical hazard that can cause illness or injury when consumed along with the food.

• Biological hazards - include bacteria, viruses, and parasites. They are by far the most important foodborne hazard in any type of food establishment. They cause most foodborne illness and are the primary target of a food safety program. Bacteria are single-celled microorganisms that require food, moisture, and warmth to multiply. Bacteria can cause foodborne infections, intoxications, and toxin-mediated infections. Most are destroyed by adequate cooking, and numbers are kept to a minimum by proper cooling during product distribution and storage.
• Chemical hazards - are toxic substances that may occur naturally or may be added during the processing of food. Examples of chemical contaminants include agricultural chemicals (i.e., pesticides, fertilizers, antibiotics), cleaning compounds, heavy metals (i.e., lead and mercury), food aditives, and food allergens. Chemicals and other non-food items should never be place near food items.
• Physical hazards - are hard or soft foreign objects in food that can cause illness and injury. They include items such as fragments of glass, metal, unfrilled toothpicks, jewelry, adhesive bandages, and human hair. These hazards result from accidental contamination and poor food handling practices that can occur at many points in the food chain from the source to the consumer.

What bacteria needs in order to multiply

Bacteria need six conditions in order to multiply. They need a source of food, a mildly acid environment, a temperature between 41ºF and 140ºF (5º and 60ºC), time, diferent oxygen requiring environment, and enough moisture. These requirements can be remembered using the acronym
F-A-T-T-O-M.

Six Conditions Bacteria Need to Multiply
F	Food - High in protein
A	Acid - pH of 4.6 to 7.0
T	Temperature - 41º to 140ºF
T	Time - two hours, four hours, etc.
O	Oxygen - different oxygen requiring environments
M	Moisture - enough water or humidity

Food- most bacteria prefer foods that are high in protein like meats, poultry, seafood, dairy products, and cooked rice, beans, and potattoes.
Acidity - most foods are acidic and have a pH less than 7.0. Most bacteria prefer a neutral environment (pH of 7.0) but are capable of growing in foods that have a pH in the range of 4.6 to 9.0.
Temperature - time and temperature are the most critical factors affecting the growth of bacteria in foods. Most disease-causing bacteria can grow within a temperature range of 41º to 140ºF (5° and 60°C). This is commonly referred to as the food "Temperature Danger Zone".
Time - bacteria need about four hours to grow to high enough numbers to cause illness. This includes the total time that a food is between 41º and 140ºF.
Oxygen - aerobic bacteria must have oxygen in order to grow. Anaerobic bacteria cannot survive when oxygen is present because it's toxic to them.
Moisture - disease-causing bacteria can only grow in foods that have a water activity higher than 0.85. Water activity is a measure of the amount of water that is not bound to the food and is therefore available for bacterial growth. Drying foods or adding salt or sugar reduces the amount of available water.

Potentially Hazardous Foods

Some types of foods have the ability to support the rapid and progressive growth of infectious and toxin-producing microorganisms. These foods are called "potentially hazardous". They are usually high in protein and have a pH above 4.6 and a water activity above 0.85. Common examples of potentially hazardous foods are red meats, poultry and raw shell eggs, fish and shellfish, and dairy products. Other potentially hazardous foods are vegetables such as cooked rice or potatoes, refried beans, and fruits such as cut cantaloupe.

Potentially hazardous foods always require special handling. If these foods are held at temperatures between 41º and 140ºF for four hours or more microorganism can grow to dangerous levels. It is critical that you control the handling and storage of potentially hazardous foods to prevent bacterial growth.

Food Safety

FDA: Foodborne Illness

Food Safety: Causes and Prevention of Foodborne Illness

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