Concept explainers
Unwelcome Dinner Guests
How do harmful bacteria get into our food? Marty foodborne illnesses result from consumption of contaminated beef. The intestinal tracts of about a third or the cattle in the United States carry bacteria that are harmful to humans, and these bacteria can be transmitted to humans when a meatpacker accidentally grinds some gut contents into hamburger. Similarly, chicken feces may splash onto eggs, setting the stage for harmful bacteria to enter the eggs through tiny cracks or when the consumer breaks the egg and its contents contact the shell. Produce such as lettuce, spinach, tomatoes, and melons can also become contaminated if farm fields are exposed to animal feces, which can be deposited by deer or wandering domestic animals or carried from nearby ranches and feedlots in dust or runoff. The warm, moist environments in which sprouts are grown provide excellent growing conditions for any harmful bacteria that may have been present on the seeds from which the sprouts were produced.
How can you protect yourself from the bacteria that share our food supply? It's easy: Clean, cook, and chill. Cleaning helps prevent the spread or pathogens. Wash your hands before preparing food, and wash all utensils and cutting boards after preparing each item. Thorough cooking is the best way to ensure that any bacteria present in food are killed. Meats, in particular, must be thoroughly cooked; food safety experts recommend using a meat thermometer to ensure that the thickest part of cooked pork or ground beef has reached 16CTF. The safe temperature for cuts or beef, veal, or lamb is 145°F; for all poultry, 165°F. The color or cooked meat can be an unreliable indicator of safety, but when a meat thermometer is unavailable, try to avoid eating meat that is still pink inside, especially ground beef. Fish should be cooked until it is opaque and flakes easily with a fork; cook eggs until both white and yolk are firm. Finally, keep stored food cold. Pathogens multiply most rapidly at temperatures between 4CT and 140CF. So get your groceries home from the store and into the refrigerator or freezer as quickly as possible. Don’t leave cooked leftovers unrefrigerated for more than 2 hours. Thaw frozen foods in the refrigerator or the microwave, not at room temperature. A little bit of attention to food safety can save you from unwelcome guests in your food.
CONSIDER THIS Consumer groups contend that we can improve food safety by giving government agencies additional funding and greater authority to inspect rood processing plants and order recalls of contaminated food. Opponents or such steps argue that we need not empower government agencies because the best protection against rood contamination is informed consumers, who will stop buying products from companies that have produced unsafe foods. Would you support or oppose additional government oversight of food safety?
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Biology
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