Old Milk

You've probably seen one kind or another of milk that keeps better than usual. How do they do it and is it as nutritous as fresh, pasteurized milk? A nice explanation can be found here. (That link should stay active for a couple of weeks, then you'll need to be a subscriber to NY Times online to get it.)

The upshot is that it loses a very small amount of nutritional value, but for the most part can be considered virtually the equal of fresh, pasteurized milk. The ultrapasteurization process heats the milk to a very high temperature for a very, very short period of time.