The New Complete Book of Food
milk will keep for three months, four to nine months, and two years. Once a can of milk is
opened, the milk should be poured into a clean container and refrigerated.
Heat treatments that make milk safer. Raw (unpasteurized) milk may contain a variety of
microorganisms, including pathogenic and harmless bacteria, plus yeasts and molds that are
destroyed when the milk is pasteurized (heated to 145°F for 30 minutes or 160°F for 15 sec-
onds). Ultrapasteurized milk has been heated to 280°F for two seconds or more. The higher
temperature destroys more microorganisms than pasteurization and prolongs the shelf life of
the milk and cream (which must be refrigerated). Ultra-high-temperature sterilization heats
the milk to 280°–302°F for two to six seconds. The milk or cream is then packed into prester-
ilized containers and aseptically sealed so that bacteria that might spoil the milk cannot enter.
Aseptically packaged milk, which is widely available in Europe, can be stored on an unrefrig-
erated grocery or kitchen shelf for as long as three months without spoiling or losing any of
its vitamins. None of these treatments will protect milk indefinitely, of course. They simply
put off the milk’s inevitable deterioration by reducing the initial microbial population.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 of bone density every year for the rest of
their lives. Men also lose bone, but at a slower rate. As a result, women are more likely to
suffer bone fractures; six of seven Americans who suffer a broken hip are women.
A lifelong 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 post-
menopausal women who are not using hormone replacement therapy should get at least
1,500 mg calcium a day, the amount of calcium in five glasses of nonfat milk.
Reduced risk of hypertension (high blood pressure). In 2008, a team of researchers from
Brigham and Women’s Hospital and the Harvard School of Public Health report in the
American Heart Association journal Hypertension that women who consume two or more
servings of fat-free milk and milk products a day reduce their risk of high blood pressure by
10 percent, compared to women who consume these products less than once a month. The
finding is specific to low-fat milk products; it does not apply to milk products with higher
fat content or to calcium and vitamin D supplements.
Use as contrast medium. Patients undergoing a CT scan or X-ray of the gastrointestinal
tract to diagnose disorders such as Crohn’s disease, diverticulitis, or tumors are often given
an oral “contrast agent,” a barium suspension (barium particles in liquid) that pools in the
intestines to outline any abnormalities on the resulting image. A report from researchers at
St. Luke’s–Roosevelt Hospital Center in New York, published in the May 2008 issue of the
American Journal of Roentgenology (the journal of the American Roentgen Ray Society), says
that giving patients whole milk instead of barium is as effective in showing abnormalities,
is less expensive, and leads to fewer adverse effects.