Over the last few decades an increasing number of dried, milk protein-rich products have come on the market. Traditionally, isolated casein was used for the manufacture of synthetic wool and buttons, for sizing paper (Le., making it smooth and easy to write on), etc. These uses have much diminished. Currently, the main use of various types of casein and of protein preparations isolated from whey is in manufactured foods. The purpose may be:
1. Increasing the nutritive value, e.g., by adding the preparations to beverages or cereal products. The high biological value and digestibility of milk protein are essential. Sometimes, partially hydrolyzed proteins, i.e., peptide mixtures, are applied for people who are allergic to certain proteins.