 |  Perspectives in Nutrition, 5/e Gordon M. Wardlaw,
Ohio State University
Margaret W. Kessel,
Ohio State University
Food Safety
Chapter 19 Summary- Bacteria and other microbes in food pose the greatest risk for food-borne
illness. In the past, salt, sugar, smoke, fermentation, and drying were used
to protect against food-borne illness. Today, careful cooking, pasteurization,
and keeping hot foods hot and cold foods cold provide additional insurance.
- Major causes of food-borne illness are the bacteria Campylobacter jejuni,
Salmonella,Shigella,Staphylococcus aureus, and Clostridium
perfringens. In addition, such bacteria as Clostridium botulinum, Listeria
monocytogenes, Yersinia enterocolitica, and Escherichia coli have
been found to cause illness.
- To protect against bacteria, cook susceptible foods thoroughly. In addition,
cover cuts on the hands, do not sneeze or cough on foods, avoid contact between
raw meat or poultry products and other food products, rapidly cool and thoroughly
reheat leftovers, and use pasteurized dairy products.
- Cross-contamination commonly causes food-borne illness. It occurs particularly
when bacteria on raw animal products contact foods that can support bacterial
growth. Because of the risk of cross-contamination, no perishable food should
be kept at room temperature for more than 1 to 2 hours (depending on the environmental
temperature), especially if it may have come in contact with raw animal products.
- Treatment for food-borne illness usually requires drinking lots of fluids,
avoiding touching food while diarrhea is present, washing hands thoroughly,
and getting bed rest. Botulism, hepatitis A infections, and trichinosis are
types of food-borne illness that require prompt medical attention.
- Food additives are used primarily to extend shelf life by preventing microbial
growth and the destruction of food components by oxygen, metals, and other substances.
Food additives are classified as those intentionally added to foods and those
that incidentally appear in foods. An intentional additive is limited to no
more than one-one-hundredth of the greatest amount that causes no observed symptoms
in animals. The Delaney Clause allows FDA to ban the use of any intentional
food additive under its jurisdiction that causes cancer.
- Antioxidants, such as BHA, BHT, vitamins E and C, and sulfites, prevent oxygen
and enzyme destruction of food products. Emulsifiers suspend fat in water, improving
the uniformity, smoothness, and body of foods such as ice cream. Common preservatives
include sodium benzoate and sorbic acid, which prevent bacterial growth. Sequestrants
bind metals and thus prevent spoilage of food from metal contamination.
- Toxic substances occur naturally in a variety of foods, such as green potatoes,
raw fish, mushrooms, raw soybeans, and raw egg whites. Cooking foods limits
their toxic effects in some cases; others are best to avoid, such as toxic mushroom
species and the green parts of potatoes.
- A variety of environmental contaminants can be found in foods. Because most
of them are fat soluble, trimming fat from meats and discarding fat that is
rendered during the cooking of meats, fish, and poultry are good steps to minimize
exposure. In addition, it's helpful to know which foods pose a special risk,
to wash fruits and vegetables thoroughly, and to discard the outer leaves of
leafy vegetables.
|
|
2002 McGraw-Hill Higher Education