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U.S. Department of Health and Human Services


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List of Terms: F

Return to Comprehensive List of Terms


Did You Know?

The Food Code has a provision for restaurants and food stores to display Consumer Advisories — which are advisory messages to consumers, usually at the point of sale or service, to help them make a more informed decision about consumption of food that may affect their health. Often found in menus, on placards or on posters, these messages concern foods such as raw or under-cooked meats, poultry, seafood, shellfish or eggs; or unpasteurized juice.

Did You Know?


The Public Health Security and Bioterrorism Preparedness and Response Act (the Bioterrorism Act) of 2002 includes very specific requirements to help ensure the safety of the U.S. food supply. Here's a summary of those rules – and how they impact industry:

Registration of Food Facilities Final Rule
Requires domestic and foreign facilities that manufacture, process, pack, or hold food for human or animal consumption in the U.S. to register with FDA.

Prior Notice of Imported Food Interim Final Rule
Requires that FDA receive advance notice of all imported food before it arrives in the U.S. to enable FDA to determine which shipments should be inspected upon arrival.

Establishment and Maintenance of Records Final Rule
Requires persons in the U.S. that manufacture, process, pack, transport, distribute, receive, hold, or import food to establish and maintain records identifying the immediate previous sources and immediate subsequent recipients of food received or released.

Administrative Detention Final Rule
Establishes procedures that FDA would use to administratively detain food when FDA has credible evidence or information that the food presents a threat of serious adverse health consequences or death to humans or animals.


 Photo of Clarence Birdseye
Photo © Copyright H. Mitchell, Courtesy of Lemelson-MT Awards Program
Clarence Birdseye

Around 1925, Clarence Birdseye of Gloucester, MA, introduced a wide range of frozen foods for the home. His process consisted of the rapid freezing of packaged food between 2 refrigerated metal plates. Though Birdseye did not develop the first frozen foods, his freezing process was a highly efficient one that preserved the original taste of a variety of foods, including fish, fruits, and vegetables.

Frozen foods have been sold since the 1920s. At first, the main product was vegetables, but later new foods, like fish sticks, were specially developed for freezing.


Did You Know?


Fungi can be microscopic or as big as a mushroom.


> Farm-to-Table Continuum 
A multi-step journey that food travels before it is consumed. (Also see the Farm-to-Table Continuum illustration below, which highlights key concepts at each step.)

Food Safety Implication: Each sector along the farm-to-table continuum plays a role in ensuring that our nation's food supply is fresh, of high quality, and safe from hazards. If a link in this continuum is broken, the safety and integrity of our nation's food supply can be threatened.

The Five Farm-to-Table StepsThe Five Farm-to-Table Steps


> Farm-to-Table Initiative
One of the directives in President Clinton's 1997 Food Safety Initiative. The Initiative involves identifying possible contamination points along the farm-to-table continuum and implementing process controls for preventing problems that might affect our nation's food supply.


> Fight BAC!TM Campaign
The Partnership for Food Safety Education's national public education project, which brings together industry, government, and consumer groups to educate Americans about the importance of using safe food-handling practices.

The campaign focuses on the 4 Cs of Food Safety, 4 simple steps people can take to fight foodborne bacteria and reduce the risk of foodborne illness. The 4 steps to food safety are: Clean, Cook, Separate (Combat Cross-Contamination), and Chill. (Also see the 4 Cs section.)

Fight BAC! logo, Keep food safe from Bacteria
BAC! is the campaign's yucky green bacteria
character who tries his best to spread
contamination wherever he goes!

The Federal Government Partners are:

  • U.S. Department of Agriculture
  • U.S. Department of Education
  • U.S. Department of Health and Human Services
  • U.S. Environmental Protection Agency


> Food Acidity
The level of acid contained in certain foods. The acid in foods helps prevent the growth of pathogenic bacteria. Acidic foods have a pH below 4.6. Some examples of high-acid foods include: all fruits (except figs), most tomatoes, jams, jellies, marmalades, fruit butters, and fermented and pickled vegetables, such as pickles and sauerkraut (Also see Acidification.)


> Foodborne Illness (also known as Foodborne Disease or Food Poisoning)
Infection or intoxication caused by the transfer of microbial or chemical contaminants (substances that spoil or infect) from food or drinking water to a human. In most cases, the contaminants are bacteria, parasites, or viruses.

Food Safety Implication: Microorganisms in food may cause illness when they are eaten and get established in the body.

Food Safety Precautions: To prevent foodborne illness, follow the 4 Cs:

  1. Clean - Wash hands, utensils, and surfaces with hot, soapy water before and after handling food.
  2. Cook - Cook foods to safe internal temperatures. Keep hot foods hot. Use a food thermometer to check (see Danger Zone for safe internal cooking temperatures for meat, poultry, seafood, eggs, and leftovers).
  3. Combat Cross-Contamination - Separate raw meat, poultry, and fish/seafood from ready-to-eat foods. Don't cross-contaminate.
  4. Chill - Refrigerate foods promptly. Keep cold foods cold.

Note: For more detailed tips, see the 4 Cs section.

Common Symptoms: Most cases of foodborne illness in healthy adults are self-limiting and of a short duration. An important warning sign of foodborne illness is bloody diarrhea. Other common acute symptoms, which can range from mild to severe, are: diarrhea, cramps, nausea, fever, vomiting, and body aches.

When to Notify a Doctor: Some foodborne illnesses, such as E. coli O157:H7, can be life-threatening, particularly for young children, the elderly, and those with weakened immune systems. Symptoms that are severe or prolonged may need to be treated. People who believe they may have contracted a foodborne illness should call their physician.

It's important to note that botulism poisoning can be fatal. The symptoms include: dry mouth, double vision followed by nausea, vomiting, and diarrhea. Later, constipation, weakness, muscle paralysis, and breathing problems may develop. It's important to get immediate medical help. With proper treatment, most victims survive (also see Clostridium botulinum).


Are some foods more likely to cause foodborne illness than others?

Just about any food can become contaminated if handled improperly. However, foods rich in protein, such as meat, poultry, fish, and seafood, are frequently involved in foodborne illness outbreaks for 2 reasons:

  1. Protein-rich foods tend to be of animal origin. Therefore, microorganisms of animal origin are frequently found in animal foods.
  2. Animal foods are rich in protein that bacteria break down into amino acids, which are an important nutrient source to some bacteria. 

Bacteria also need moisture in order to survive and reproduce. Thus, they thrive in foods with high moisture content. These include starchy, egg-rich foods and cream-based foods, such as potato or pasta salads, cream-based soups, and custard or cream pies.

How sick can I get from eating contaminated food?

There are many variables. Your age, general health, and how much contaminated food you ate are all factors. The most common symptoms are diarrhea, nausea, vomiting, and abdominal pain, but you don't necessarily get all the symptoms. At-risk people can become very ill and can even die from foodborne illness because their immune systems are less able to fight off the bacteria.

Can the symptoms of foodborne illness be mistaken for the flu?

Yes. Foodborne illness often shows itself as flu-like symptoms such as nausea, vomiting, diarrhea, or fever, so many people may not recognize that the illness is caused by bacteria or other pathogens in food.

Experts from the Centers for Disease Control and Prevention (CDC) report that many of the intestinal illnesses commonly referred to as stomach flu are actually caused by food-borne pathogens. People do not associate these illnesses with food because the onset of symptoms often occurs 2 or more days after the contaminated food was eaten.

What to Do If You Think You Have a Contaminated Product: The first rule of thumb is: Don't use the product. If you have a question about meat, poultry, or eggs, call the U.S. Department of Agriculture (USDA) Meat and Poultry Hotline at 1-888 MPHotline or 1-888-674-6854. The TTY number is 1-800-256-7072. For questions regarding all other foods, call the Food and Drug Administration (FDA) Food Information Line at (888) SAFE FOOD.

Dispelling Foodborne Illness Myths

Many people have common misconceptions regarding foodborne illness. Here are some common foodborne illness myths, along with their corresponding facts.

Myth: Foodborne illness is always the result of the last food you ate.

Fact: Symptoms of foodborne illness usually occur 24 hours or more after eating a particular food and can last up to 10 days. Within 24 hours, you would have eaten a wide range of foods, and any of these foods could have contributed to the illness. Thus, it's often difficult to determine which food actually caused the illness.

Myth: The only time food is not safe to eat is when it looks or smells spoiled.

Fact: Many people assume that because food spoilage is visible, this is the only time that food is not safe to eat. Food that looks and smells fresh may contain harmful pathogens that you cannot see. Food-spoilage bacteria are not the same as foodborne bacteria.

Food-spoilage bacteria are responsible for the deterioration of food. This includes milk going sour or lunch meat turning green or slimy. Spoilage is more of a food-quality issue than a food-safety issue. Basic sanitary practices and proper refrigeration will reduce or retard bacterial growth and subsequent spoilage. Most people will not get sick from food-spoilage bacteria, but it is recommended that you don't eat any food that is spoiled, as it may cause some people to have a reaction, such as nausea.

Foodborne illness bacteria contaminate food and make it unsafe to eat. If these bacteria are present in large enough numbers, they can cause someone who eats the contaminated food to become ill. The best way to keep foodborne illness bacteria from multiplying in food is to follow these simple rules: Keep hot foods hot, keep cold foods cold, and keep hands and food-preparation areas clean. (See the4 Cs section.)

Myth: Foodborne illness isn't serious, and it's something that doesn't happen very often.

Fact: Foodborne illness can affect anyone at any time. If you eat food that is contaminated, you could become sick. People in the at-risk groups are particularly vulnerable. In addition, what most people think is a 24-hour stomach flu can actually be foodborne illness. (Also see theFAQ section to the right, and CDC's Foodborne Illness Statistics below.)

Foodborne Illness Stats
The following statistics are estimates based on reported cases of foodborne illnesses in the United States:
Number of: People per Year
Diseases caused by food and resulting in hospitalizations 128,000
Gastrointestinal illnesses 48,000,000
Deaths 3,000
-- Centers for Disease Control and Prevention (CDC)

> Food Code 
A reference guide published by the Food and Drug Administration (FDA). The guide instructs retail outlets, such as restaurants, grocery stores, and institutions, such as nursing homes, on how to prevent foodborne illness. It consists of a model code which is adopted by nearly 3,000 State, local and tribal jurisdictions as the legal basis for their food inspection program for safeguarding public health. It ensures that food is safe and unadulterated (free from impurities) and honestly presented to the consumer. It also provides references, public health reasons and explanations for code provisions, guidelines, and sample forms. The FDA first published the Food Code in 1993 and revises it every 4 years.


> Food Defense
Food defense is the protection of food products from intentional adulteration by biological, chemical, physical, or radiological agents.


> Food and Drug Administration (FDA)
An agency of the U.S. government, with offices and laboratories nationwide, that is authorized by Congress to inspect, test, approve, and set safety standards for all food, except meat, poultry, and processed eggs, which are under the jurisdiction of the U.S. Department of Agriculture (USDA). The agency also ensures that all of these products are labeled truthfully with the information that people need to use them safely and properly.

Who Regulates What?
Food and Drug Administration (FDA) U.S. Department of Agriculture (USDA)
  • All food, except meat, poultry, and processed eggs
  • Chemicals
  • Food Additives
  • Food and drugs for pets and farm animals
  • Household devices (e.g., microwave ovens)
  • Meat
  • Poultry
  • Processed eggs

> Food Engineering (see Biotechnology)


> Food Inspection
The process of checking and assuring that the nation's food supply is safe to eat and that proper sanitary conditions are enforced.

Food Safety Implication: The U.S. Food and Drug Administration (FDA), the U.S. Department of Agriculture (USDA), and state and local regulatory agencies are responsible for protecting the safety and wholesomeness of food. Agency scientists test samples to see if any substances are present in unacceptable amounts. If contaminants are identified, the agencies take corrective action. The agencies also inspect foods that are imported to the United States from other countries to make sure they are in compliance with government standards, and set labeling standards to help consumers know what is in the foods they buy.

If I forget to follow some of the basic food safety rules, won't heating or reheating foods kill foodborne bacteria?

To be safe, always follow the 4 Cs of Food Safety rules when preparing, serving, and cooking foods. Proper heating and reheating will kill foodborne bacteria. However, some foodborne bacteria produce poisons or toxins that are not destroyed by high cooking temperatures if the food is left out at room temperature for an extended period of time. An example is the foodborne bacteria Staphylococcus. This bacterium produces a toxin that can develop in cooked foods that sit out at room temperature for more than 2 hours.


> Food Isolate
A microorganism that is derived from food for the purpose of identifying or characterizing it.


> Food Manufacturing
The large-scale preparation of food products from raw animal and plant material utilizing principles of food technology.


> FoodNet
The Foodborne Diseases Active Surveillance Network, a collaborative project conducted by the Centers for Disease Control and Prevention (CDC), the Food and Drug Administration (FDA), the U.S. Department of Agriculture Food Safety and Inspection Service, and participating states. The Network produces national estimates of the burden and sources of specific diseases in the United States through active surveillance and other studies.

FoodNet collects data for the following food- borne diseases: Campylobacter, Escherichia coli O157:H7, Listeria, Salmonella, Shigella, Yersinia, Vibrio, and parasites, such as Cryptosporidium and Cyclospora.

The Network was established in 1995. As of the year 2006, there were 10 FoodNet sites, which include: Connecticut, Georgia, Maryland, Minnesota, New Mexico, Oregon, and Tennessee and selected counties in California, Colorado, and New York. They represent a total population of 44 million people (approximately 15% of the U.S. population).


> Food Poisoning
The traditional term for the illness caused by eating contaminated food. Today, "foodborne illness" is the term used by food safety experts. (Also see Foodborne Illness.)


> Food Research
The careful systematic study, investigation, and compilation of information about foods and their components.

 Food Safety
A system to ensure that illness or harm will not result from eating food. Everyone along the farm-to-table continuum - farm (production), processing, transportation, retail, and table (home) - plays a role in keeping our nation's food supply safe.


> Food Safety Initiative
Started by President Clinton in 1997, this project has provided new funds for needed improvements in food-safety and begun to unify the various food-safety initiatives being carried out by federal agencies sharing responsibility for food safety. As a result, there have been improvements in surveillance, research, inspection, outbreak response, risk assessment, and education.


> Food Safety and Inspection Service (FSIS)
The public health agency in the U.S. Department of Agriculture that is responsible for ensuring that the nation's commercial supply of meat, poultry, and egg products is safe, wholesome, and correctly labeled and packaged, as required by the Federal Meat Inspection Act, the Poultry Products Inspection Act, and the Egg Products Inspection Act.


> Food Science
The discipline in which biology, physical sciences, and engineering are used to study the nature of foods, the causes of their deterioration, and the principles underlying food processing.


> Food Technology
The application of food science to the selection, preservation, processing, packaging, distribution, and the use of safe, nutritious, and wholesome food.


> Food Thermometer
A special device that measures the internal temperature of cooked foods, such as meat, poultry, and any combination dishes to ensure that a safe temperature is reached.

Drawing of a Digital Instant Read food thermometer
Most Digital Instant Read food thermometers are
accurate to within plus or minus 1° to 2° F (0.5° C to 1° C).

Food Safety Implication: A food thermometer ensures that a sufficient temperature is reached, so that harmful bacteria like Salmonella and Escherichia coli O157:H7 are destroyed.

How to Check the Accuracy of a Food Thermometer: Immerse the thermometer stem a minimum of 2 inches in boiling water, touching neither the sides nor the bottom of the glass. At sea level, the temperature should read 212° F (100° C).

Thermometers should be checked periodically, following the manufacturer's recommendations. Many food thermometers have a calibration nut under the dial that can be adjusted. Check the package for instructions.


> Four Steps to Food Safety (also known as 4 Cs of Food Safety)
The Fight BAC!TM Campaign's 4 food safety messages for preventing foodborne illness. (Also see Fight BAC!TM Campaign.)

  1. Clean - Wash hands, kitchen utensils, and surfaces with hot, soapy water before and after handling food.
  2. Cook - Cook foods to safe internal temperatures. Keep hot foods hot. Use a food thermometer to check. 
  3. Separate (Combat Cross-Contamination) - Separate raw meat, poultry, and seafood from ready-to-eat foods. Don't cross-contaminate.
  4. Chill - Refrigerate foods promptly. Keep cold foods cold.

Note: For more detailed tips, see the 4 Cs section.

FIGHT BAC! Keep Food Safe From Bacteria (TM) Clean, Separate, Chill, and Cook

Will food that's stored in a freezer for a long period of time be safe to eat?

Safe food that was properly handled and stored at 0° F (-18° C) will remain safe. Only the quality of foods suffers with lengthy freezer storage. Tenderness, flavor, aroma, juiciness, and color of frozen foods can all be affected.
Does freezing affect the level of nutrients contained in foods?
Fortunately, the freezing process itself does not reduce nutrients, and, for meat and poultry products, there is little change in protein value during freezing.
Does freezer burn make food unsafe?
Freezer burn is a food-quality issue, not a food safety issue. It appears as grayish-brown leathery spots on frozen food. It occurs when air reaches the food's surface and dries out the product. This can happen when food is not securely wrapped in air-tight packaging. Color changes result from chemical changes in the food's pigment. Although undesirable, freezer burn does not make the food unsafe. It merely causes dry spots in foods. Cut away these areas either before or after cooking the food. When freezing food in plastic bags, push all the air out before sealing.
What is freeze-drying?
Freeze-drying is another method of preserving food. During this process, water is removed from food while the food is still frozen by a process known as sublimation. The frozen food is cooled to about -20° F (-29° C). Then it is placed on trays in a refrigerated vacuum chamber, and heat is carefully applied. As a result, any water in the food is changed directly from ice to water vapor without first changing into water. Freeze-dried products include: soups, tea, and instant coffee.

> Freezer Gel (see Cold Pack)   


> Freezing
A method of food preservation accomplished by rapidly lowering the food temperature to below 32° F (0° C), at a minimum, and then storing food at a temperature of 0° F (-18° C).

Food Safety Implication: Freezing is a critical food preservation method, since it stops microbial growth. Freezing does not kill microorganisms - therefore, it's important to properly handle meat, poultry, and seafood when cooking and defrosting these foods. (Also see the 4 Cs section.)

How It Works: Freezing keeps food safe by causing foodborne illness microbes to enter a dormant stage.

Food Safety Precautions:

  • Keep your freezer unit set to 0° F (-18° C). Check the temperature of your unit regularly with an appliance thermometer.
  • To keep harmful bacteria from growing and multiplying, store foods that you won't be using right away in the freezer.
  • Don't overload your freezer unit. Cold air must circulate to keep the food frozen.
  • Refer to the "Refrigerator and Freezer Storage" chart for proper food-quality storage times.
  • Thaw foods safely. For proper thawing tips, see the 4 Cs section.


> Fumigation
The standard agricultural method of applying chemicals and other treatments to crops to drive away and kill disease-spreading insects and other pests.

Also, fumigation is sometimes used at the processing stage to rid foods, such as spices, fruits, and vegetables, from contamination from insects. Spices are notorious for the presence of pathogens because bacteria easily permeate foods contacting the ground.


> Fungus (singular) or Fungi (plural) 
Simple plants called "Saprophytes" that lack chlorophyll (the green coloring that plants use to make food). Because fungi lack chlorophyll, they cannot produce their own food. Therefore, they must take carbohydrates, proteins, and other nutrients from the animals, plants, or decaying matter on which they live.

Food Safety Implication: Some fungi play a major role in a number of foods that we eat. However, other fungi can cause great damage and disease.

Where They Live: Fungi are found in the air, soil, plants, animals, water, and in some foods.

Types of Fungi: Fungi are any of about 50,000 species of organisms that include:

  • Yeast - single-cell fungi; can cause skin infections;
  • Mushrooms - multi-cell fungi;
  • Molds and Mildew - multi-cell fungi; mold and mildew spores are allergens (substances that induce allergies);
  • Smuts - Disease-causing fungi of corn, wheat, and onion; and
  • Rusts - Disease-causing fungi of wheat, oats, beans, asparagus, snapdragon, and hollyhock.

Good Fungi: Many fungi are beneficial. For instance, yeast is a fungus that causes bread to rise by producing carbon dioxide from the carbohydrates in the dough. Other fungi, such as mushrooms and truffles, are considered delicacies. Certain molds found in cheeses, such as Camembert and Roquefort, age cheeses and serve as flavor enhancers.

Note: Cheese made from unpasteurized milk may contain harmful bacteria in addition to fungi. At-risk groups should avoid eating cheese made from unpasteurized milk, such as Camembert and Roquefort.

Harmful Fungi: Fungi like smuts and rusts destroy many crops and other plants. Others produce diseases in people and animals. Some mushrooms are poisonous and can cause serious illness or death if eaten. Molds spoil many kinds of food. In damp climates, mildews and other fungi can ruin clothing, bookbindings, and other materials.