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A Recipe for Food Safety

Almost any food can be contaminated. Though most foodborne illness comes from raw animal foods—such as eggs, meats and dairy products—fruits and vegetables may carry germs, too. According to the CDC, alfalfa and clover sprouts were tied to thousands of cases of gastrointestinal illness and two deaths in the 1990s. In 2006, packaged fresh spinach was tied to more than 100 cases of illness and three deaths from E. coli contamination.

The CDC says each year, foodborne diseases make about 48 million Americans sick and kill up to 3,000. As warm weather arrives, it's vital to protect yourself from foodborne illness. You'll probably eat more raw fruits and vegetables, enjoy picnics and barbecues, and store or transport food under less than perfect conditions during warm months than at any other time of the year. 

Be careful with produce

The USDA advises you to treat fruits and vegetables with care, just as you would animal-based foods. Fruits and vegetables often are imported from nations without rigid safety standards; fresh manure used to fertilize vegetables can contaminate them. Alfalfa sprouts and other sprouts usually eaten raw are sprouted in conditions that are ideal not only for the sprouts, but also for microbes. Unpasteurized fruit juice can be contaminated if there are pathogens in or on the fruit used to make the juice.

Rinse fresh fruits and vegetables in running tap water to remove visible dirt and grime. Don't skip fruit with inedible rinds; bacteria on rinds can spread to the flesh of the fruit when you slice them. Avoid leaving cut produce at room temperature for many hours. 

Handle susceptible foods carefully

The USDA says bacteria need moisture, protein, and carbohydrates to grow. Potato salad and macaroni salad offer ideal conditions, so keep these dishes well chilled. Never let a starchy salad touch raw meat or utensils used on raw meats. Avoid cross-contaminating foods by washing hands, utensils, and cutting boards after they have been in contact with raw meat or poultry and before they touch another food. 

Contain bacteria

Prevent bacteria from spreading from raw to cooked meats. If you carry a platter of burgers to the grill, use a second clean plate to take the meat from the grill after cooking. 

Keep foods cold

Refrigerate leftovers promptly if they are not going to be eaten within four hours. Keep in mind that refrigeration doesn't kill bacteria, but it stops or slows them from growing. The bacterium Listeria is an exception in that it grows well in the cold. Left long enough, food can still go bad in the fridge—meats from bacteria; and fruits, vegetables, and breads from molds. 

Understand sell-by and use-by dates

Sell by applies to stores, which can keep things colder in the back room before display than you do in your refrigerator. Even if the sell-by date on raw poultry is a week away, you've only got two or three days to use it once you bring it home. The use-by date refers to an unopened package. 

Keep food preparation areas clean

Wipe your sink with diluted bleach once a week. Avoid using sponges; change your dishcloth at least once daily. 

Four key ingredients

1. Clean. Wash your hands with soap and water. Discard outer lettuce and cabbage leaves. Wash fruits and vegetables carefully. 

2. Chill. Refrigerate leftovers promptly. When you arrive home from the grocery store, put refrigerated items away first. Don't let milk sit out during a meal; pour what you or your family needs and put the container back in the fridge immediately. 

3. Cook. Cook meat well. The following are guidelines from the FDA:

  • Beef, veal, and lamb steaks and roasts—145 degrees Fahreinheit (63 degrees Celsius) for medium rare, 160 degrees Fahreinheit (71 degrees Celsius) for medium, and 170 degrees Fahreinheit (77 degrees Celsius) for well done

  • Ground pork and ground beef—160 degrees Fahreinheit (71 degrees Celsius) 

  • Poultry, ground poultry, poultry breasts, whole poultry—165 degrees Fahreinheit (74 degrees Celsius) 

  • Fin fish—145 degrees Fahreinheit (63 degrees Celsius) or until the flesh is opaque and separates easily with a fork

  • Shrimp, lobster, and crabs—the meat should be pearly and opaque

  • Clams, oysters, and mussels—until the shells are open 

4. Separate. Don't let raw foods, such as vegetables, touch raw meats. 

Major threats

Foodborne diseases ranging from gastroenteritis to cancer can be caused by toxins produced by bacteria and fungi, by bacterial organisms invading body tissues, and by viruses and parasites. Below are some of the more common diseases: 

Botulism (Clostridium botulinum)

  • Botulism is a rare, serious paralytic illness caused by a nerve toxin produced by the bacterium Clostridium botulinum, commonly found in the soil. Here are some of the ways botulism can get into a person: foodborne botulism is caused by eating foods that contain the botulism toxin; a wound can become infected with botulism organisms that then produce the toxin in the wound; and infant botulism is caused by an infant consuming the spores of the botulinum bacteria, which then grow in the intestines and release toxin. All forms of botulism can be fatal and are considered medical emergencies.

  • Symptoms include double or blurred vision, drooping eyelids, slurred speech, difficulty swallowing, dry mouth, muscle weakness, paralysis, and difficulty breathing. Infants with botulism appear lethargic, feed poorly, are constipated, have a weak cry, and have poor muscle tone.

  • To prevent infection, don't use food in cracked jars or cans that are swollen, leaking, or damaged, or that have bulging ends. Don't give honey or foods that contain honey to children younger than age 1.

Clostridium (Clostridium species, not botulinum)

  • Primary symptoms are diarrhea and cramping eight to 24 hours after eating spoiled food. Other symptoms may include nausea and fever. Vomiting may sometimes occur. This illness typically resolves in a few days.

  • This illness is thought to develop mostly from meats and meat products that have been warmed too long or rewarmed. Prepare food fresh and eat it soon after preparation.

C. jejuni (Campylobacter jejuni)

  • Most cases of campylobacteriosis are associated with raw poultry or eating raw or undercooked poultry meat. A very small number of Campylobacter organisms can cause illness in humans. Even one drop of juice from raw chicken meat can infect a person. Chickens infected with C. jejuni show no signs of illness. Other sources of infection are unpasteurized milk if the cow has an infection with Campylobacter in her udder or the milk is contaminated with manure; surface water can become contaminated from infected feces from cows or wild birds. It is common in the developing world, so travelers are at risk for becoming infected.

  • Symptoms include muscle pain, headache, and fever followed by diarrhea, abdominal pain, and nausea.

  • Avoid raw or undercooked poultry (it is safe it any juices run clear and the inside is cooked to 170 degrees Fahreinheit (77 degrees Celsius) for breast meat, and 180 degrees Fahreinheit (82 degrees Celsius) for thigh meat), unpasteurized milk, and untreated water. Cook ground meats thoroughly.

E. coli (Escherichia coli)

  • There are hundreds of strains of E. coli, most are harmless and live in the intestines of healthy humans and animals. E. coli O157:H7 is one strain though, that produces a powerful toxin and can cause severe illness. It can be found in the intestines of healthy cattle; on the udders of cows or on equipment used in milking; on sprouts, lettuce, salami, unpasteurized milk, and juice; and in sewage-contaminated water.

  • Symptoms include abdominal cramps, stomach pain, and watery or bloody diarrhea. Severe cases can be fatal.

  • To prevent infection, eat only thoroughly cooked meat and poultry. Wash produce, especially lettuce, thoroughly. Avoid unpasteurized milk and unpasteurized apple cider.

Listeria (Listeria monocytogenes)

  • Listeria monocytogenes is found in soil and water. Vegetables can become contaminated from the soil or from manure used as fertilizer. Animals can carry the bacterium without appearing ill and can contaminate foods of animal origin such as meats and dairy products. You get listeriosis by eating food contaminated with Listeria.

  • Symptoms include nausea, diarrhea, muscle aches, headache, and fever. It can be fatal in the young and elderly.

  • Prevention measures include washing raw vegetables thoroughly, especially lettuce and cabbage leaves. Cook meat and poultry thoroughly and avoid unpasteurized dairy foods, such as raw milk and cheese. Carefully observe sell by and use by dates on processed foods.

Salmonella (Salmonella species)

  • Salmonella live in the intestinal tracts of humans and other animals, including birds. Salmonella usually are transmitted to humans by eating foods contaminated with animal feces, including vegetables.

  • Symptoms include nausea, vomiting, abdominal cramps, headache, diarrhea, and fever.

  • Thoroughly cook meat, poultry, fish, and eggs. Don't eat raw eggs in salad dressing and baking dough. Use separate cutting surfaces and knives to prepare raw and cooked foods. Never eat unpasteurized, raw, or undercooked foods of animal origin.

Staph (Staphylococcus aureus)

  • Staphylococci are normally present in the nasal passages, throats, hair, and skin of more than 50 percent of healthy people. Symptoms are caused by the toxin produced by bacteria in foods that require considerable handling during preparation, and that are kept at slightly elevated temperatures after preparation.

  • Symptoms, which usually begin soon after eating foods contaminated with the toxin, include nausea, vomiting, chills, and shallow breathing.

  • To prevent infection, don't keep prepared foods, particularly cooked and cured meats, cheeses, and meat salads, sitting at room temperature for more than two hours. Store meat, fish, and poultry in the coldest part of the refrigerator.