BACKGROUND: Food science researchers subjected a panel of human tasters to samples of very old food. They discovered that even 20-year-old dried milk and 28-year-old rolled oats were still edible -- and sometimes even tasted okay. So a lot of food well past the manufacturer's expiration date might still be edible for years or decades to come.
ABOUT THE STUDY: Food scientists have long maintained that certain foodstuffs ý salt, granulated crystal sugar, seeds, and wheat kernels, for example ý can be stored indefinitely at room temperature or below. But what about more processed grains, such as rolled oats? So the researchers prepared oatmeal from 16 samples of regular and quick-cooking rolled oats that had been stored up to 28 years in sealed containers. A panel of tasters rated the oats on aroma, texture, flavor, aftertaste and overall acceptability. The scientists also analyzed the samples' nutritional quality. Tasters rated the quality of the old oats from 4.8 to 6.7 on an ascending scale from 1 to 9. Three-fourths of the testers considered the old oats acceptable in an emergency.
WHY DOES FOOD SPOIL? Processing and improper storage practices can expose food items to heat or oxygen, which is what causes deterioration. In ancient times, salt was used to cure meats and fish to preserve them longer, while sugar is added to fruits to prevent spoilage. Certain herbs, spices and vinegar can also be used as preservatives, along with anti-oxidants, most notably Vitamins C and E. In processed foods, certain FDA-approved chemical additives also help extend shelf life.
CONSUMER TIPS: If you're stocking up on food in case of an emergency, be sure to include lots of water: one gallon per person per day for drinking, cooking and personal hygiene. The best foods for stockpiling are canned or freeze-dried soups; dried meats, fruits and vegetables; ready-to-eat-cereals and crackers; peanut butter, granola, or trail mix; energy bars, cookies and crackers; powdered or evaporated milk; and basic stables such as sugar, salt, pepper, rice, coffee or tea. Use only food-grade containers, and make sure the storage area is cool and dry, since hot, humid environments speed up spoilage. Date and rotate foods at least once a year.
The American Society for Microbiology contributed to the information contained in the TV portion of this report.