ABSTRACT
During the two decades, considerable interest has been given to the development of sophisticated extraction procedures for food proteins in order to satisfy the increasing needs of different industrial sectors for tailor-made products. Proteins, in addition to contributing to the basic nutritional status of foods, are exploited as functional ingredients for modifying or enhancing the textural and rheological characteristics of foodstuffs. Milk collected by the dairy industry contains lipids (—40 g/liter) organized in fat globules. Most extraction procedures for milk proteins use skim milk as the starting material. Consequently, whole milk is centrifuged in a separator comprising conical discs and running at 5,000 rpm at around 50°C. There are two principal established methods for the production of whole casein on an industrial scale: isoelectric precipitation and rennet coagulation. The whey protein fraction of milk has unquestionably the highest nutritional value for human beings, far ahead of any other source of protein.
