Preserving Your Food: Cross-Contamination, Thawing and Reheating

Preserving food properly is a great way to stretch your grocery dollar and provide tasty, healthful meals year-round. But preserving food improperly can cost you time and money, create unnecessary waste and, most significantly, be very hazardous to your health. Safely handle food from start to finish by following these tips.

Cross-contamination
Cross-contamination is the transfer of harmful bacteria to food from other foods, objects, or people. It may cause diarrhea, nausea, vomiting, dehydration, and abdominal cramps. To prevent cross-contamination, follow these guidelines:

• When shopping, separate raw meat, poultry, and seafood from other foods in your cart and at checkout. Place these foods in plastic bags to prevent their juices from dripping onto other foods. Raw juices often contain harmful bacteria. Take the same precautions when refrigerating, placing raw meats on the bottom shelf.
• Wash your hands thoroughly with soap and hot water before and after handling food.
• Use separate or thoroughly rewashed cooking utensils and cutting boards for each stage of meal preparation. For example, don't use the same tongs on raw food and cooked food. Also use separate dishtowels or sponges for each stage; they are a haven for bacteria.
• Marinate food only in the refrigerator, not on the counter. Sauce that is used to marinate raw meat, poultry, or seafood should not be used on cooked foods, unless it is boiled just before using.

Thawing
There are four ways to safely thaw frozen food:

• In the refrigerator at 41 degrees F or colder. This is best for large pieces of meat like a whole turkey, ham, or roast, but it takes the longest. Allow 24 hours for every five pounds of meat.
• As part of cooking. This works well for small amounts of food like vegetables, hamburger patties, and seafood. Be sure to cook to the required safe minimum internal temperature.
• In a microwave oven. This works best for smaller cuts of meat such as chicken breasts or pork tenderloin. After thawing in the microwave, immediately cook food in the microwave or by conventional methods.
• Under drinkable, running water (70 degrees F or less). This is best for food that can be thawed in two hours or less, such as jumbo shrimp, strips of chicken, and other smaller cuts of meat.

Reheating
If you intend to reheat foods, there are two things to keep in mind: how long the food has been at room temperature, and how you will store it.

Food poisoning bacteria grow best in the temperature range of 41 degrees F to 140 degrees F. You must ensure that food spends no more than two hours in this "temperature danger zone." Food left out longer can develop a heat-resistant toxin that cooking can't destroy.

If the food is safe to refrigerate or freeze, use only small, shallow containers, three inches tall or less, and cover them completely. Don't stack these containers next to others; leave air space around them. This will promote rapid, even cooling of the food. In a large, deep container, food in the center stays warm longer. Dangerous bacteria may grow in this warm spot without making the food look or smell bad.

Keep foods chilled at 40 degrees F or less until you are ready to reheat them. Then, reheat rapidly to 165 degrees F to kill bacteria that have grown in the food while it was cooling from 140 degrees F to 41 degrees F. Make sure you heat leftover food completely. Leftovers that are merely "warmed" and not heated throughout are much more likely to cause food poisoning.