07.11.07
Watch out for incompatible foods
That is, foods that make other foods spoil. Via gezellig-girl.com, this note from Wild Oats:
Americans throw out 25 percent of the produce they buy because it’s gone bad. How to stop the waste? Know when to shop, learn which fruits and veggies don’t get along and which ones to keep out of the fridge. — By Shelley Levitt (originally printed in Wild Oats Magazine).
Perhaps you do it once a week. Perhaps only when you trace those sulfurous odors to your refrigerator’s crisper drawers. But eventually, you toss out spoiled vegetables and fruits. Lots of them. Researchers at the University of Arizona recently spent a year tracking families’ food-use habits. Working with the United States Department of Agriculture, they interviewed the families about their eating habits, collected their grocery receipts, watched them prepare meals, and then sifted through every last discarded lettuce leaf, slice of bread, burger and bean.
The results, reported in 2002, were pretty shocking. The families tossed out an average of 470 pounds of food per year—about 14 percent of all food brought into the home—at an annual cost of $600. Every day, they discarded more than half a pound of fruits and veggies. In total, Americans chuck a quarter of all the produce they buy, mostly because it’s gone bad, says Timothy Jones, PhD, contemporary archaeologist at the University of Arizona. Nationally, we dump $43 billion worth of food every year.
Wasting produce is, well, a waste—bad for our wallets and bad for the environment. Plus, who wants to make a salad when confronted with a bin of rotting sludge? All this led us to ask: How can we keep produce fresh longer?
The ABCs of Fresh
“The main way to lengthen shelf life is by using cold temperatures to slow food’s respiration, or ‘breathing’ process,” explains Marita Cantwell, PhD, a postharvest specialist at the University of California, Davis. In general, the warmer the temperature, the faster the rate of respiration, which is why refrigeration is critical for most produce. But while you want to slow it down, you don’t want to stop the breathing altogether. “The worst thing to do is seal produce in an airtight bag,” says Barry Swanson, a food scientist at Washington State University. “You’ll suffocate it and speed up decay.” Some fruits emit ethylene, an odorless, colorless gas that speeds ripening and can lead to the premature decay of nearby ethylene-sensitive vegetables. Put spinach or kale in the same bin as peaches or apples, and the greens will turn yellow and limp in just a couple of days. So the first trick is to separate produce that emits ethylene from produce that’s sensitive to it. (See “Gas Wars,” below).
