Dry ice is really crystallized carbon dioxide. It doesn't produce water when it melts and is generally used only for long-term refrigeration. Touching dry ice with bare hands can result in burns. dry milk Milk from which almost all the moisture has been removed. Dry (also called powdered) milk is less expensive and easier to store than fresh milk but has a disadvantage in that it never tastes quite like the real thing. It comes in three basic formswhole milk, nonfat milk and buttermilk. Because of its milk fat content, dry whole milk must be refrigerated. Nonfat dry milk is available in regular and instant forms; the former tastes slightly better, while the latter mixes more easily. Powdered buttermilk is simply desiccated buttermilk and is generally used for baking. Until opened, dry nonfat milk and buttermilk can be kept in a cool, dry place for up to 6 months. Refrigerating opened packages will help retain their freshness. A USDA "U.S. Extra Grade" shield on the label signifies that the product meets exacting government quality standards. Dry milks may or may not be fortified with vitamins A and D.
From The Food Lover's Companion, Fourth edition by Sharon Tyler Herbst and Ron Herbst. Copyright © 2007, 2001, 1995, 1990 by Barron's Educational Series, Inc.