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Storing This Food
Refrigerate all cultured milk products. At 40°F, buttermilk will stay fresh for two to three
weeks, sour cream for three to four weeks, and yogurt for three to six weeks. Keep the con-
tainers tightly closed so the milks do not absorb odors from other foods.Preparing This Food
Do not “whip” yogurt or sour cream before adding to another dish. The motion will break
the curds and make the product watery.What Happens When You Cook This Food
Cultured milk products are more unstable than plain milks; they separate quickly when
heated. Stir them in gently just before serving.How Other Kinds of Processing Affect This Food
Freezing. Ordinarily, cultured milk products separate easily when frozen. Commercially
frozen yogurt contains gelatin and other emulsifiers to make the product creamy and keep
it from separating. Freezing inactivates but does not destroy the bacteria in yogurt; if there
were live bacteria in the yogurt when it was frozen, they will still be there when it’s thawed.
Nutritionally, frozen yogurt made from whole milk is similar to ice cream; frozen yogurt
made from skim milk is similar to ice milk.Medical Uses and/or Benefits
Protection against osteoporosis. The most common form of osteoporosis (literally, “bones full
of holes”) is an age-related loss of bone density most obvious in postmenopausal women.
Starting at menopause, women may lose 1 percent a year of their bone density every year until
they die. Men also lose bone, but at a slower rate. As a result, women are more likely than men
to suffer bone fractures. Six of seven Americans who suffer a broken hip are women.
A life-long diet with adequate amounts of calcium can help stave off bone loss later
in life. Current studies and two National Institutes of Health Conferences suggest that
postmenopausal women who are not using hormone replacement therapy should get at least
1,500 mg calcium a day, the equivalent of the calcium in slightly more than three cups yogurt
made with nonfat milk.
Protection against antibiotic-related illness. Gastric upset, primarily diarrhea, is a common side
effect of antibiotic therapy because antibiotics eliminate beneficial bacteria in the gastrointes-
tinal tract along with harmful microorganisms. In 2008, a report in the British Medical Journal
confirmed earlier studies suggesting that hospitalized patients on antibiotics who were given
“probiotic” cultured milks—yogurts containing beneficial microorganisms—had a significantly