Why is Milk Homogenized?

Homogenization became common soon after pasteurization. It solved two practical problems in the dairy industry. The first was the cream line. With pasteurization, milk could be shipped long distances. In transit the cream rose to the top, which meant the most valuable part of the milk-the fat-was unevenly divided from one customer to another. Homogenization distributes the cream evenly, so everyone gets a share.

The other problem, according to author and dairy farmer Joann Grohman, was purely aesthetic. After pasteurization, dead white blood cells and bacteria form a sludge that sinks to the bottom of the milk. Homogenization spreads the unsightly sludge throughout the milk and makes it invisible. Ironically, white blood cells and beneficial bacteria are one of the healthiest things about raw milk. But once they're zapped with heat they're useless, and rightly regarded as a waste product.

For many years after it was first introduced, many Americans declined to buy homogenized milk. 'Skeptical consumers were disturbed both by the change in flavor and the absence of the cream line at the top of the bottle,' writes Schmid. 'The amount of cream and its color had always provided a way for consumers to judge the quality of the milk.' (Fat has always been the measure of milk. Even today, dairy farmers are paid more for fat content above 3.5%.) But dairy companies persisted with a campaign to win public acceptance for homogenization, and by the 1950s, most milk was homogenized.

Many people believe that homogenized milk is more difficult to digest and that the small fat particles contribute to the syndrome known as 'leaky gut.' Some people have suggested that homogenization contributes to atherosclerosis, but the evidence is not strong. Homogenized cream takes twice as long to whip as unhomogenized cream. Health and practical matters aside, unhomogenized milk and cream taste better.


[ back to top ]