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List of Terms: C

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Did You Know?


Nicolas Appert

Nicolas Appert, a French candy maker, invented the canning process. How did it all start? In 1810, the government of Napoleon offered a financial reward to anyone who could figure out how to preserve food for its army and navy. Appert won the prize for his new method of preserving foods by cooking and then reheating the food in sealed-glass jars.








Campylobacter jejuni 
This foodborne pathogen is the most common bacterial cause of diarrhea in the United States, resulting in 1 to 6 million illnesses each year. Children under age 1 have the highest rate of Campylobacter species infections.

Campylobacter jejuni
Photo: Lan Hu, Ph.D., Dennis J. Kopecko, Ph.D., and Ben Tall, Ph.D.
Campylobacter jejuni

Sources: Raw milk, untreated water, and raw and undercooked meat, poultry, or shellfish.


Incubation: Generally 2 to 5 days after ingestion.

Symptoms: Diarrhea (sometimes bloody), abdominal cramps, fever, muscle pain, headache, and nausea.

Duration: 7 to 10 days.


> Canning  
A method of preserving food by placing it in airtight, vacuum-sealed containers and destroying microorganisms through heat- processing at 250° F (121° C).

Human Pathogen Association: Clostridium botulinum.

Food Safety Implication: Many raw foods, especially raw vegetables, contain heat-resistant spores of Clostridium botulinum. (See photo below.) While canning can help foods last longer, if it is not done properly, the spores will grow and produce a deadly toxin. If the toxin is consumed, a person could develop botulism, a serious foodborne illness. If a person's diaphragm is affected, he or she will not be able to breathe and could die. Fortunately, botulism is a very rare disease in the United States and is treatable if diagnosed early. (Also see Clostridium botulinum.)

How It Works: First, food is washed and prepared before packing it in a sterile (free of microorganisms) tin-coated steel can or glass jar. To prevent food spoilage and kill any pathogenic organisms, the container is then subjected to high heat - at least 250° F (121° C) - for a certain amount of time. Cooking times vary depending on the food.

FAQAre there nutritional differences between fresh foods and canned foods?

The heating process during canning destroys from one-third to one-half of vitamins A and C, riboflavin, and thiamin. For every year the food is stored, canned food loses an additional 5 to 20% of these vitamins. However, the amounts of other vitamins are only slightly lower in canned food than in fresh food.

Most produce will begin to lose some of its nutrients when harvested. When produce is handled properly and canned quickly after harvest, it can be more nutritious than fresh produce sold in stores.

When refrigerated, fresh produce will lose half or more of some of its vitamins within 1 to 2 weeks. If it’s not kept chilled or preserved, nearly half of the vitamins may be lost within a few days of harvesting. For optimum nutrition, it is generally recommended that a person eat a variety of foods.

Food Safety Precautions: Exercise safe canning practices at home by following these tips:

  • Use a pressure cooker to heat low-acid foods, such as red meats, seafood, poultry, milk, and all fresh vegetables, except for most tomatoes. (Tomatoes are usually considered an acidic food, but some are now known to have pH values slightly above 4.6.) Low-acid foods (with pH values higher than 4.6) are not acidic enough to prevent the growth of the bacterium, Clostridium botulinum.

Pressure Cooker
Photo: National Presto Industries, Inc.
Pressure Cooker

  • Acidic foods can be safely processed in a boiling-water canner because the combination of 212° F (100° C) heat and acidity will inactivate bacteria and spores. Some examples of high-acid foods include: all fruits (except figs), most tomatoes, jams, jellies, marmalades, fruit butters, and fermented and pickled (treated with brine or vinegar solution to inhibit the growth of microorganisms) vegetables, such as pickles and sauerkraut. Acidic foods (with a pH of 4.6 or lower) contain enough acidity to destroy bacteria more rapidly when heated.
Pressure Canner
Photo: National Presto Industries, Inc.
Pressure Canner

  • Always label canned items with the name of the food and the date it was canned.
  • Store canned food in a cool, clean, and dry place.
  • Don't use food from cans with dents, bulges, leaks, or rust spots.
  • Canned or bottled food can stay fit to eat for up to 2 years, but for best quality, use canned food within a year.
  • Notes on Canning

  • The acidity level in foods can be increased by adding lemon juice, citric acid, or vinegar.
  • Pressure alone does not kill microorganisms. As steam generates in a sealed vessel, the pressure builds and temperatures above 212° F (100° C) are achieved. The bacteria and spores are destroyed by the high temperatures applied to the food for the proper amount of time.
  • Pressure cooking preserves the texture, color, flavor, aroma, and nutrients of food because it can reach a temperature of about 250° F (121° C), thus shortening the required cooking time. Be sure to follow the cooker manufacturer's directions.
 Did You Know?

To cover the head of a pin, it would require a sheet of about 10,000 human cells.

A human being is composed of more than 75 trillion cells.

> Cell  
In biology, it is the basic unit of which all living things are composed.

The Main Parts of a Prokaryotic (lacking a distinct nucleus) Cell are:

  • The cytoplasm - the fluid inside the cell that contains the parts for converting food material into energy and new cell materials.
  • The cell membrane and/or wall - surrounds the cytoplasm and holds everything together and controls the passage of material into and out of the cell.

Note: A prokaryotic cell does not have a well-defined nucleus enclosing its genetic material.

A Prokaryotic Bacterial Cell Diagram
A Prokaryotic Bacterial Cell


> Center for Food Safety and Applied Nutrition (CFSAN)  
One of the 7 centers within the Food and Drug Administration that regulates $240 billion worth of domestic food, $15 billion of imported foods, and $15 billion worth of cosmetics sold across state lines. This regulation takes place from the products' point of U.S. entry or processing to their point of sale.

With a work force of about 800, the Center promotes and protects public health and economic interest by ensuring that food is safe, nutritious, wholesome, and accurately labeled. It also ensures that cosmetics are safe and honestly, accurately, and informatively labeled.


> Center for Veterinary Medicine (CVM)  
A division of the Food and Drug Administration that regulates the safe and effective use of drugs for use in food-producing animals. CVM also regulates the feed that animals eat to ensure that it does not harbor zoonotic (animal-related) pathogens that can be transmitted to people. (Also see Zoonoses/Zoonosis.)

CVM also contributes to the surveillance activities of the Food Safety Initiative. The division has developed and coordinated the National Antimicrobial Resistance Monitoring System (NARMS), a collaboration between the FDA, the U.S. Department of Agriculture/ Agricultural Research Service, and the Centers for Disease Control and Prevention. NARMS monitors shifts in susceptibility to 17 antimicrobial drugs of zoonotic enteric organisms from veterinary and human services.


> Centers for Disease Control and Prevention (CDC)  
An agency of the U.S. Department of Health and Human Services (HHS) that promotes health and quality of life by preventing and controlling disease, injury, and disability. When there is an outbreak of foodborne illness, the CDC uses trace-back techniques to identify the source of foodborne bacteria in foods to prevent further exposure or spread of infection. (Also see Health and Human Services and PulseNet.)

 Did You Know?

Clostridium botulinum can form spores that can survive the boiling temperature (212° F, 100° C). Therefore, home-canned meat, poultry, fish, and vegetable products require pressure canning to reach 250° F (121° C) for a long enough period of time to kill the spores.

Most cases of Clostridium perfringens are caused by failure to keep food hot. These bacteria can grow better above 120° F (49° C). It's important to keep foods out of the Danger Zone, the temperature range usually between 40° F (4° C) and 140° F (60° C).

> Clostridium botulinum  
This bacterium lives in the soil and in the bottom of lakes, oceans, etc. It is also sometimes found in moist, low-acid food, containing less than 2% oxygen, and stored between 40° F (4° C) and 120° F (49° C). This bacterium produces a toxin that causes botulism, a disease characterized by muscle paralysis.

Proper heat processing destroys Clostridium botulinum in canned food. Freezer temperatures inhibit its growth in frozen food. Low moisture controls its growth in dried food. High oxygen controls its growth in fresh foods.

Clostridium botulinum
Clostridium botulinum

Sources: Home-canned and prepared foods, vacuum-packed and tightly-wrapped food, meat products, seafood, and herbal cooking oils.


Incubation: 4 to 36 hours after ingesting.

Symptoms: 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 because botulism can be fatal. With proper treatment, most victims survive.

Duration: It can take from 1 week to a full year to recover.


> Clostridium perfringens  
A foodborne pathogen that persists as heat-stable spores. If foods are only moderately cooked and allowed to remain at room temperature, the spores can germinate and produce a harmful toxin.

Clostridium perfringens
Photo: Courtesy of Audry Wanger, Ph.D.,
University of Texas Medical School

Clostridium perfringens

Sources: Meat and meat products.


Incubation: Usually occurs 8 to 12 hours after eating contaminated food.

Symptoms: Abdominal pain, diarrhea, and sometimes nausea and vomiting.

Duration: The illness is usually mild and lasts a day or less; however, symptoms can be more serious in the elderly or people with weakened immune systems.


> Cold Chain
Maintaining proper temperatures through-out the farm-to-table continuum to prevent the growth of foodborne bacteria along the way.

Food Safety Implication: Along the farm-to-table continuum, it's critical that food is kept at the proper temperature to keep it ready for market and safe to eat. For example, fresh produce is quickly cooled after harvesting to slow down the ripening process and reduce the spread of decay. The temperatures are carefully controlled throughout the processing operations. The temperature inside shipping containers is controlled to maintain proper temperature during transit. The cold chain continues when food is stored, displayed, and served at retail outlets. Consumers also need to properly transport and store food at home.


> Cold Pack (also known as Freezer Gel)
A cold source that is used in coolers to help keep foods and beverages cold.

Drawing of an Ice Pack
A cold pack is useful in helping food
stay cold when you're on the run!

Food Safety Implication: Perishable food should be kept at 40° F (4° C) or colder to slow the growth of harmful bacteria. A cold pack in your cooler helps foods stay cold.

Food Safety Precautions:

  • When transporting perishable foods, always use cold packs or ice in your cooler.
  • Use cold packs in lunch boxes to keep sandwiches, other perishables, and beverages cold.


> Coliforms
The most common form of bacteria found in untreated water. The presence of this group of non-pathogenic bacteria in drinking water is an indicator that the water may be contaminated by sewage and/or other similar material and should not be ingested. Fecal coliform bacteria of which E. coli is one type, live in the intestines of warm-blooded animals. Pathogenic coliforms can cause diarrhea and other serious health problems if the bacteria are ingested.


> Competitive Exclusion
The process in which non-pathogenic bacteria, naturally found in the mature animal's gastrointestinal (GI) tract are provided to newborn animals to prevent infection from pathogens.

Food Safety Implication: The idea behind competitive exclusion is to prevent harmful bacteria, like Salmonella, from colonizing and infecting young animals. This in turn reduces foodborne illness caused by animal products. However, it's important to note that even treated animals can become contaminated during food processing or in the kitchen, so food handlers must continue to practice the 4 Cs of Food Safety when preparing raw meat or animal products, such as raw eggs. (See the 4 Cs section.)

How It Works: Competitive exclusion is currently being used with chickens; however, it may have application for other animals, such as pigs and even humans.

Young chickens are born with an undeveloped gastrointestinal (GI) tract. As part of normal development, bacteria will colonize the (GI) tract. The non-pathogenic bacteria mixture is sprayed on day-old chicks. The chicks ingest the drug as they preen (groom themselves). These good bacteria colonize the chick's (GI) tract where Salmonella would usually live.

When Salmonella arrive in the intestine, the "good" bacteria have already colonized the gut. They have taken up residence in the available binding sites. They have eaten the available food, and they have created an environment favorable for themselves. In turn, the Salmonella have no food, no binding sites, and an unfriendly environment, so they cannot survive.

Competitive exclusion gives the chicks the beneficial gut "microflora" (bacteria and other microorganisms that normally inhabit the intestines) they need at a time when they are most vulnerable to Salmonella colonization. It also gives them the natural disease resistance of a mature, healthy bird - making it virtually impossible for Salmonella to multiply. Competitive exclusion also reduces Salmonella in the environment because there are fewer infected birds to contaminate the farm.

Chicks being sprayed
Chicks being sprayed with beneficial bacteria,
which will prevent infection from Salmonella

 Did You Know?
The practice of composting can be traced back 2,000 years to the ancient Romans and Greeks. By the 19th century, most U.S. farmers knew that composting was a useful method for nourishing soil and building healthy plants, but they didn’t know how or why it worked. It’s only been within the past 50 years that scientists have understood the process!

  > Composting
A managed, agricultural process in which organic materials, including animal manure and other wastes, are digested aerobically (with oxygen) or anaerobically (without oxygen) by microbial action. Composting can be done successfully on a large scale by farmers, waste management companies, or on a small scale at home.

Food Safety Implication: When composting is carefully controlled and managed and the appropriate conditions are achieved, the high temperature generated can kill most pathogens in a few weeks.

However, composting that is not done properly can pose a health risk. For example, animal or human wastes that are thrown into a compost pile at home may be contaminated with pathogenic bacteria, which may not be killed during the composting process and can contaminate the plants or water around them. Thus, the use of improperly-prepared compost as a garden fertilizer creates the risk of foodborne illness.


> Conjugation
The process in which deoxyribonucleic acid (DNA) is transferred from one bacterium to another through a specialized tube. Conjugation, sometimes referred to as "mating," is a parasexual form of reproduction.


> Contamination
The unintended presence of harmful substances or microorganisms in food.


> Critical Control Point (see Hazard Analysis and Critical Control Point)  


> Cross-Contamination
The transfer of bacteria from foods, hands, utensils, or food preparation surfaces to a food. This can be a particular problem with liquids from raw meat, poultry, and seafood, in that harmful bacteria can be transmitted to previously uncontaminated foods or surfaces. (Also see the 4 Cs section.)  


> Cryptosporidium
A parasite that is the cause of severe, life-threatening disease, particularly in patients with AIDS.


Sources: Fecally-contaminated water, food, or environmental surfaces.


Incubation: 2 to 10 days after ingestion.

Symptoms: Diarrhea, nausea, abdominal cramps, low-grade fever. The illness is more chronic in patients with AIDS, also resulting in voluminous watery diarrhea, weight loss, anorexia, and malaise.

Duration: 7 to 14 days.


> Cyclospora
A single-cell parasite that causes cyclosporiasis, a diarrheal illness.

Sources: Fresh produce or water that was contaminated with infected human stool.


Incubation: Generally 1 week.

Symptoms: Diarrhea, loss of appetite, substantial loss of weight, bloating, increased gas, stomach cramps, nausea, vomiting, muscle aches, low-grade fever, and fatigue.

Duration: From a few days to a month or longer.


> Cytoplasm (see Cell)