What Happens to Milk When It's Pasteurized?

If you look at a container of milk, you'll find that the milk is pasteurized.

This process was named after French scientist Louis Pasteur, who invented it. Pasteurization kills any bacteria that might be present in milk, and assures that it will be wholesome.

How is milk pasteurized? It's simply heated. Pasteur found that if milk is heated to a certain temperature, no bacteria can survive in the milk.

There are two ways to pasteurize milk. One is to heat it to at least 143° F. for 30 minutes, and the second is to heat it to 160° F. for at least 15 seconds.

In the United States, milk was first pasteurized in 1895, in New York City. Today, all milk that is sold in stores is first pasteurized.