Chocolate milk is a sweetened, usually cold, cocoa
-flavored milk
drink. It is created when chocolate syrup (or chocolate powder) is mixed with milk (from cows, goats, soy, rice, etc). It can be purchased pre-mixed or made at home with either cocoa powder
and a sweetener (such as sugar
or a sugar substitute
), or with melted chocolate
, chocolate syrup
, or chocolate milk mix. Other ingredients, such as starch
, salt, carrageenan
, vanilla
, or artificial flavoring
may be added. Chocolate milk should be refrigerated
like plain milk
. A suspension
is required to blend in the two flavors (milk and chocolate, hence the name of the mixed drink). When chocolate milk begins to spoil, it gives off a coffee-like odor, unlike plain milk, and due to the properties of the carrageenan
, certain brands are known to, after a certain amount of time, coagulate
into a viscous, chunky bottom layer and a thin, watery upper layer. It was invented by Hans Sloane
in the late 1680s.
Supplement
Some nutritionists have criticized chocolate milk for its high sugar content and its relationship to childhood obesity. Of the milk served in U.S. schools, 71 percent is flavored. In New York City, school food officials say nearly 60 percent of the 100 million cartons served each year are fat-free chocolate milk. Because chocolate milk can contain twice as much sugar as plain low-fat milk from added sugars, some school districts have stopped serving it, including those in Berkeley, CA, and Washington, DC. In the US, 32 percent of children and teens are overweight and at risk for diabetes, high blood pressure and other issues related to obesity.
A number of studies indicate that chocolate milk aids in recovery when taken after athletic workouts. A study at Loughborough University found that Milk was an effective rehydration drink. In a 2010 report it was studied with 13 college soccer players with results in favor of chocolate milk workout supplementation. In a 2006 study, authors believed the benefits were due to its ratio of carbohydrates to protein, among other nutritional properties. However, this study was small in scale with only nine athletes and partially funded by the dairy industry. Furthermore, the study compared chocolate milk to two energy drinks and unflavored milk was not used as a comparison, so it is unknown if chocolate milk is superior to unflavored milk as a recovery drink.
A 2005 study by the New York City (NYC) Department of Education found that by removing whole milk and replacing it with low-fat to fat-free chocolate milk, students were served an estimated 5,960 fewer calories and 619 fewer grams of fat per year.
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Chocolate supplies oxalic acid, which reacts with the calcium in the milk producing calcium oxalate, thus preventing the calcium from being absorbed in the intestine. However, it is present in small enough amounts that the effect on calcium absorption is negligible. As chocolate contains relatively small amounts of oxalate, it is unclear to what extent chocolate consumption affects healthy people who eat calcium-rich diets. In a 2008 study, participants who consumed one or more servings of chocolate on a daily basis had lower bone density and strength than those participants who ate a serving of chocolate six times a week or less. Researchers believe this may be due to oxalate inhibiting calcium absorption — but it could also be due to the chocolate's sugar content, which may increase calcium excretion. It is clear, however, that consuming foods high in oxalate — and in turn their effect on calcium absorption — is a more significant concern for people with oxalate kidney stones, which occur when there is too much oxalate in the urine. These people, especially, should reduce their oxalate intake and increase their calcium intake. However, the high magnesium content in chocolate is likely to reduce the risk of stone formation somewhat, because like citrate, magnesium is also an inhibitor of urinary crystal formation.
A November 2009 study conducted by scientists in Barcelona, Spain suggests that regularly consuming skim milk with cocoa rich in flavonoids may reduce inflammation and slow or prevent the development of atherosclerosis. However, the study notes that its effects are not as pronounced as seen in consumption of red wine.