Whey is the liquid that remains after milk is curdled to produce cheese. It contains proteins, some fat, and carbohydrates. Whey and whey proteins are currently used in the domestic food industry as livestock feed. Some whey is exported, but potentially could be used to produce bioenergy and bioproducts in the U.S. About 1 billion pounds of dry whey are produced annually, with New York, Utah, Washington, and Wisconsin being major producers. Recent prices of dried whey (used in livestock feed) have ranged from $0.16 to $0.29 per pound.