Functional Properties of Nonfat Dairy Ingredients — A Review. Modification of Lactose and Products Containing Whey Proteins,

Abstract

Whey proteins can be modified by a variety of physical, chemical, or enzymatic processes. The principal whey proteins, α-lactalbumin and β-lactoglobulin, are sensitive to heat. Once denatured, ionic and pH conditions can be altered and combined with centrifugation to produce traditional products such as lactalbumin. Relatively undentatured whey proteins can be selectively depleted of ions and lactose removed to yield a wide range of whey protein concentrates in which physical properties have been tailored to specific product application. The principal whey proteins can be separated by ionic as well as pH and heating techniques but these have not been commercialized as yet. Chemical modification through succinylation, amidation, phosphorylation, esterification, and thiol-reducing agents effectively modifies functional properties but usually at the expense of nutritional value. Enzymatic modification is used primarily to improve solubility of denatured proteins, but choice of enzyme and conditions is critical to avoid bitter flavors. Lactose is the most ubiquitous component of milk and presents problems due to lack of utility. Modification through enzymatic hydrolysis, isomerization, oxidation, reduction, or selective fermentation processes shows some promise in expanding utility of lactose. © 1985, American Dairy Science Association. All rights reserved.