Whey is the liquid by-product of cheese and cottage cheese manufacture from
milk. Each kg of cheese produced results in the production of about 9 kg
of whey. In 1993, the U.S. cheese and cottage cheese industry produced
approximately 23 x 10^6 m^3 (6 x 10^9 gal) of whey (National Agricultural Statistics
Service, 1994). Most of this is used directly as livestock feed or
concentrated or dehydrated and used in human food and animal feed manufacture.
Depending on the locality and economic factors, 20 to 100% of the
whey produced is applied for beneficial effects on soils, or is land applied as
a disposal procedure
