How to Determine the Shelf Life of Foods

When you get around to cleaning the cobwebs out of your pantry and
wiping the mystery spills from your refrigerator, you're bound to come
across some scary science projects. To determine what's perfectly fine
and what's petrified, follow this guide.

Instructions

1. Remember that not all foods are created equal: Depending on the quality of the food when you purchased it, and how it has been stored (temperature, packaging), foods may deteriorate more quickly or last longer.

2. Know your terminology. "Best if used by" is not a "purchase by" or safety date; it's an estimate for how long the food is expected to retain its flavor, texture and freshness.

3. Follow expiration dates on foods--they mean what they say. Throw out anything in your pantry or refrigerator that's expired. Give yourself some leeway with "sell by" dates. You don't have to throw out the rest of the milk that morning. Your nose knows: If it still smells fine, you can drink it.

4. Check packaged and boxed foods for the bar code, which is not easy to decipher. It may be coded by month, day and year, such as YYMMDD or MMDDYY. Or it may be coded using Julian numbers, whereby January 1 would be 001 and December 31 would be 365. In even more convoluted codes, letters A through M (omitting the letter I) are often assigned to the months, with A being January and M being December, plus a numeric day, either preceded or followed by the numeric year.

5. Be aware that canned foods lose from 5 to 20 percent of their nutritional content each year, depending on length of storage and temperature. Store all canned foods in a cool, dry, dark place (less than 70 degrees F (21 C) is preferred; 50 degrees F (10 C) is optimal). Try to use up canned foods within a year--rotate older ones in front of the shelf and the newer ones in back.

6. Store raw meat (beef, lamb, veal, pork) for up to five days in the refrigerator; four to twelve months in the freezer. Poultry and ground meats can be kept in the fridge for up to two days before cooking and one to four months in the freezer. For a comprehensive list of how long foods can be safely stored, see sites such as www.foodsafety.gov and pastrywiz.com/storage.

7. Package foods correctly to lengthen their storage life. Use airtight containers in the fridge and freezer. Cool foods before freezing. Reduce freezer burn by wrapping foods in plastic wrap and then sealing in an air-tight zipper locked plastic bag.

Tips & Warnings

• Use up leftovers within four days. Mayonnaise-based sauces and dressings should be used within two to three days. Refrigerate what you'll use for the next day or two, and freeze the rest for up to four months.

• Examine which foods you toss because they don't get used up. Are you overbuying? Update your master shopping list to save time and money.

• Once you open foods, the dates become moot if the contents are perishable. Use foods as quickly as possible after opening.

• Food frozen at 0 degrees F (-18 C) will be safe to eat indefinitely, but the quality, nutrient level and flavor will deteriorate.

• Food dating is not required by U.S. law, except on baby food and infant formula.

• Flour and other dry goods can be frozen.

• Don't buy canned foods that are dented, oozing or damaged. Aluminum can leak into foods.