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What are the symptoms of foodborne illness?
Can the symptoms of foodborne illness be mistaken for the flu?
Why is it important to use a cooking thermometer?
Where can I obtain more information on foodborne illness?
If spores can survive cooking, freezing, and some sanitizing measures, how can spores be prevented from the start?
If a person who was infected by Salmonella typhi begins to feel okay, does this mean he or she has stopped shedding the bacteria?
If I forget to follow some of the basic food safety rules, won't heating or reheating foods kill foodborne bacteria?
One of the food safety rules is to wash hands in hot, soapy water. Does hot water kill bacteria?
How can I clean my hands when water is not available, such as when traveling or picnicking away from home?
What is the safest way to defrost meat, poultry, and fish products?
How long can you store food in a refrigerator or freezer?
What is the safest way to handle and prepare eggs?
If cooked meat and poultry look pink, does it mean that the food is not done?
What are the food safety concerns with sprouts?
What food storage tips can help prevent foodborne illness?
How and where can I getting food safety training?
Can a Food Establishment use produce from Farmers Markets?
Is it okay to keep reheating food?

Q.

What are the symptoms of foodborne illness?

A.

Symptoms
Common symptoms of foodborne illness include diarrhea, abdominal cramping, fever, headache, vomiting, severe exhaustion, and sometimes blood or pus in the stools. However, symptoms will vary according to the type of bacteria and by the amount of contaminants eaten.

In rare instances, symptoms may come on as early as a half hour after eating the contaminated food but they typically do not develop for several days or weeks. Symptoms of viral or parasitic illnesses may not appear for several weeks after exposure. Symptoms usually last only a day or two, but in some cases can persist a week to 10 days. For most healthy people, foodborne illnesses are neither long-lasting nor life-threatening. However, they can be severe in the very young, the very old, and people with certain diseases and conditions.

These conditions include:

  • liver disease - either from excessive alcohol use, viral hepatitis, or other causes
  • hemochromatosis (an iron disorder)
  • diabetes
  • stomach problems - including previous stomach surgery; low stomach acid (for example, from antacid use); cancer
  • immune disorders - including HIV infection
  • long-term steroid use - as for asthma and arthritis.

When symptoms are severe, the victim should see a doctor or get emergency help. This is especially important for those who are most vulnerable. For mild cases of foodborne illness, the individual should drink plenty of liquids to replace fluids lost through vomiting and diarrhea.


Q.

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

A.

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.


Q.

Why is it important to use a cooking thermometer?

A.

One of the critical factors in fighting food-borne illness is temperature. Bacteria grow slowly at low temperatures and multiply rapidly at mid-range temperatures. To be safe, a product must be cooked to an internal temperature high enough to destroy harmful bacteria. Using a meat thermometer is a reliable way to ensure that food has reached the proper temperature. However, to be effective, thermometers must be used properly and calibrated correctly. If the thermometer is inserted incorrectly, or placed in the wrong area, the reading may not accurately reflect the internal temperature of the product. In general, the thermometer should be placed in the thickest part of the food, away from bone, fat or gristle. Read the manufacturer's instructions on how to calibrate (check the accuracy of) the thermometer. According to the U.S. Department of Agriculture, temperature is the only way to gauge whether food is sufficiently cooked. USDA research reveals that the "color test" can give consumers misleading information about the safety of the foods they are preparing, since cooked color varies considerably. For example, freezing and thawing may influence a meat's tendency to brown prematurely.


Q.

Where can I obtain more information on foodborne illness?

A.

Food and Drug Administration
On the World Wide Web, USDA/FDA Foodborne Illness Educational Materials Database at http://www.nal.usda.gov/foodborne/wais.shtml, visit the "Bad Bug Book" at www.cfsan.fda.gov/~mow/intro.html and the National Food Safety Initiative at www.cfsan.fda.gov/~dms/fs-toc.html. Also see www.foodsafety.gov.

Call FDA's Food Information line at 1-888-SAFEFOOD (1-888-723-3366). Recorded information 24 hours a day, every day. FDA public affairs specialists are available to answer questions from 10 a.m. to 4 p.m. Eastern time, Monday through Friday.

Write to FDA's Center for Food Safety and Applied Nutrition, Consumer Education Staff (HFS-555), 5100 Paint Branch Parkway, College Park, MD 20740.

Order FDA's food safety video "Dirty Little Secrets: Kitchen Food Safety" for $8.95. Call 202-861-0500 and ask for the duplication department or write to: Interface Video Systems, P.O. Box 57138, Washington, DC 20037. You can also see a 10-second clip from the video on this Website.

U.S. Department of Agriculture
On the World Wide Web, visit www.fsis.usda.gov

Call USDA's Meat and Poultry Hotline at 1-800-535-4555. Recorded information 24 hours a day, every day. Staffed 10:00 a.m. to 4:00 p.m. Eastern time, Monday through Friday.

Write to USDA, FSIS, Food Safety and Education Communications Staff, Room 2932-S, 1400 Independence Ave., S.W., Washington, DC 20250-3700.


Q.

If spores can survive cooking, freezing, and some sanitizing measures, how can spores be prevented from the start?

A.

Conquering spores is not an easy process because spore growth can occur anywhere. There are food safety precautions you can take. Do not hold food in the danger zone, the temperature range in which most bacteria can grow. This range is usually below 40° F (4° C). Some pathogenic bacteria can grow at 32° F (0° C) or above 140° F (60° C). Spores can germinate into pathogenic bacteria in the danger zone and multiply in food. For example, any cooked dish will generally have all the bacteria killed, but not the spores. When in doubt, throw the food out! (Also see Danger Zone.)

Spore growth is also relevant to improperly canned foods. The Food and Drug Administration (FDA) makes sure that canned foods are processed in a safe manner. Consumers should be careful not to buy cans with dents, bulges, leaks, or rust spots. A failure in the canning process can allow spores to generate gas and germinate into pathogenic bacteria. (Also see Canning.)


Q.

If a person who was infected by Salmonella typhi begins to feel okay, does this mean he or she has stopped shedding the bacteria?

A.

Not necessarily. Even if symptoms seem to go away, a person may still be carrying Salmonella typhi. If so, the illness could return and he or she could pass the disease to other people. In fact, if the person works at a job where he or she handles food or cares for small children, that person may be barred legally from going back to work until a doctor has determined that the person no longer carries any typhoid bacteria. Therefore, it's important for the person to consult a doctor to ensure that the bacteria no longer remain in his or her body.


Q.

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

A.

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.


Q.

One of the food safety rules is to wash hands in hot, soapy water. Does hot water kill bacteria?

A.

Hot water that is comfortable for washing hands is not hot enough to kill bacteria. The body oils on your hands hold soils and bacteria, so hot or warm, soapy water is more effective than cold, soapy water at removing those oily soils and the bacteria in them.


Q.

How can I clean my hands when water is not available, such as when traveling or picnicking away from home?

A.

You can use disposable wipes or a hand gel sanitizer. You use the gel without water. The alcohol in the gel kills the germs on your hands. You can find disposable wipes and hand gel sanitizers in most supermarkets and drugstores.


Q.

What is the safest way to defrost meat, poultry, and fish products?

A.

Food safety experts recommend thawing foods in the refrigerator or the microwave oven or putting the package in a water-tight plastic bag submerged in cold water and changing the water every 30 minutes. Changing the water ensures that the food is kept cold, an important factor for slowing bacterial growth that may occur on the outer thawed portions while the inner areas are still thawing.

When microwaving, follow package directions. Leave about 2 inches (about 5 centimeters) between the food and the inside surface of the microwave to allow heat to circulate. Smaller items will defrost more evenly than larger pieces of food. Foods defrosted in the microwave oven should be cooked immediately after thawing.

Do not thaw meat, poultry and fish products on the counter or in the sink without cold water; bacteria can multiply rapidly at room temperature.


Q.

How long can you store food in a refrigerator or freezer?

A.

The answer to this question can be found in a document entitled: When in Doubt--Throw It Out which is maintained on the web site of the Partnership for Food Safety Education.


Q.

What is the safest way to handle and prepare eggs?

A.

The answer to this question can be found in a document entitled: Playing it Safe With Eggs.


Q.

If cooked meat and poultry look pink, does it mean that the food is not done?

A.

The color of cooked meat and poultry is not a sure sign of its degree of doneness. For instance, hamburgers and fresh pork can remain pink even after cooking to temperatures of 160° F (71° C) or higher. The meat of smoked turkey is always pink because components within the smoke bind to the muscle pigment to form a stable pink pigment. Only by using a food thermometer can you accurately determine that meat has reached a safe internal temperature.


Q.

What are the food safety concerns with sprouts?

A.

The answer to this question can be found in a July 1999 Press Release issued by Department of Health & Human Services.


Q.

What food storage tips can help prevent foodborne illness?

A.

Safe Storage
The first rule of food storage in the home is to refrigerate or freeze perishables right away. The refrigerator temperature should be 5 degrees Celsius (41 degrees Fahrenheit), and the freezer should be -18 C (0 F). Check both "fridge" and freezer periodically with a good thermometer.

Poultry and meat heading for the refrigerator may be stored as purchased in the plastic wrap for a day or two. If only part of the meat or poultry is going to be used right away, it can be wrapped loosely for refrigerator storage. Just make sure juices can't escape to contaminate other foods. Wrap tightly foods destined for the freezer. Leftovers should be stored in tight containers. Store eggs in their carton in the refrigerator itself rather than on the door, where the temperature is warmer.

Seafood should always be kept in the refrigerator or freezer until preparation time.

Don't crowd the refrigerator or freezer so tightly that air can't circulate. Check the leftovers in covered dishes and storage bags daily for spoilage. Anything that looks or smells suspicious should be thrown out.

A sure sign of spoilage is the presence of mold, which can grow even under refrigeration. While not a major health threat, mold can make food unappetizing.

Most moldy foods should be thrown out. But you might be able to save molding hard cheeses, salami, and firm fruits and vegetables if you cut out not only the mold but a large area around it. Cutting the larger area around the mold is important because much of the mold growth is below the surface of the food.

Many items besides fresh meats, vegetables, and dairy products need to be kept cold. For instance, mayonnaise and ketchup should go in the refrigerator after opening. Always check the labels on cans or jars to determine how the contents should be stored. If you've neglected to refrigerate items, it's usually best to throw them out.

For foods that can be stored at room temperature, some precautions will help make sure they remain safe. Potatoes and onions should not be stored under the sink, because leakage from the pipes can damage the food. Potatoes don't belong in the refrigerator either. Store them in a cool, dry place. Don't store foods near household cleaning products and chemicals.

Check canned goods to see whether any are sticky on the outside. This may indicate a leak. Newly purchased cans that appear to be leaking should be returned to the store, which should notify FDA.

Q. How and where can I get food safety training?
A.

The National Park Service enforces the latest version of the FDA Food Code. First and formost, you must be sure that the training you select meets this criteria. A great resource for understanding and locating training courses in your area is at the Food Safety Training & Education Allience (FSTEA) website.

Q. Can a Food Establishment use produce from Farmers Markets?
A.

Background: Technically, because farmers markets usually offer products that are not from regulated or inspected producers, these operations would not normally be considered approved under the definitions used in the model food code. Approximately 12% of foodborne outbreaks can be attributed to produce. However, it is traditional, especially in the summer months for many chefs to seek out and use these sources of produce, viewing them as "fresher" sources of product. While a fair number of outbreaks have been traced back to produce in general, there is no evidence that I can find in the literature that farmers markets, per se, are a higher risk than commercial sources of produce.

Interpretation/Guidance: The NPS Public Health Program will allow the use of farmers markets as a source of produce with two provisions:

1. The use of farmers markets as a source of produce for NPS food service facilities shall be an occasional practice, intended to supplement commercial supplies with local, seasonal, or hard to find produce items. The majority of produce used in any operation must come from a commercial (inspected) supply.

2. If an operator wishes to make one or more unregulated supplier a routine or majority source of produce, then the supplier must provide written evidence that they have substantial and purposeful control over food safety issues. Evidence of this effort shall be in the form of active managerial controls of food safety hazards as demonstrated by practices that follow the FDA guidance titled, Guide to Minimize Microbial Food Safety Hazards for Fresh Fruits and Vegetables. This document can be found on the internet at, http://www.fda.gov/Food/GuidanceComplianceRegulatoryInformation/GuidanceDocuments/ProduceandPlanProducts/ucm064574.htm
. Evidence of these controls must be made available to the NPS Public Health Consultant.

-top-

Q. Is it okay to keep reheating food?
A. In general, if foods are cooled properly, there is no limit to the number of times that can occur and still have safe food. However, there is a high likelihood that the foods nutritional qualities might significantly degrade with each time the food is reheated as high temperatures tend to breakdown nutrients.

Some food products contain heat resistant bacterial spores and these spores may produce new bacteria if the cooling process takes too long. There are also a few bacteria that can produce heat resistant toxins. If a food is allowed to cool too slowly, these bacteria may multiply and make these toxins, which are then not destroyed during any reheating process. For these reasons, it is critical that the time it takes for any food to go from cook to cool (41°F or below) be as short as possible. We use the following time and temperature guides:

135°F to 70°F within 2 hours and then from 70° to 41° or less in an additional 4 hours. So... foods should take no longer than 6 hours to get from 135° to 41° or below.

If this does not happen correctly, then reheating can become less sure and less effective, especially through several repetitions. This is the reason that many people suggest only one reheat cycle. Basically it is advice that errs on the side of caution.
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