Protein hydrolysates as special nutritional ingredients

Abstract

The use of hydrolyzed proteins as food ingredients dates back to the late 19th century, beginning in Europe and the Far East. These hydrolyzed proteins, which were produced by acid or enzymatic hydrolysis of vegetable and animal proteins, were used for flavoring purposes in bouillon, soups, and sauces, and they gained rapid consumer acceptance. It was only in the late 1930s and early 1940s that a parenteral grade of protein hydrolysate made by pancreatic enzyme digestion of casein was used for parenteral feeding. The discovery in the 1950s that careful charcoal treatment of casein hydrolysate could remove most of the aromatic amino acids (phenylalanine, tyrosine, and tryptophan) brought about the development of special formula for the dietary management of infants who suffer from phenylketonuria or tyrosinosis. Since then, protein hydrolysates have been widely used as the nitrogen source for the interal feeding of individuals who have specific nutritional and physiological needs. These include patients with impaired gastrointestinal function (e.g., Crohn's disease), short bowel syndrome, or specific organ disease (e.g., pancreatitis, renal and hepatic). Protein hydrolysates have also found application in sports nutrition, weight control diets, and nutritional supplements. More recently, protein hydrolysates have been used in dietetic products designed for the nutritional management of cancer patients and individuals with AIDS. However, the widest use of protein hydrolysates as nutritional ingredients has been for feeding infants with intact protein hypersensitivity. The use of protein hydrolysates in these products is based on the premise that predigested proteins, when fed as amino acids and peptides, provide essential nitrogen in a non-antigenic, easily absorbed form.