Manufacture of bioactive peptide-rich concentrates from Whey: Characterization of pilot process

This work was focused on the manufacture, at pilot scale, of cow whey protein and peptide concentrates, using selective filtration techniques-associated with hydrolysis brought about by proteolytic enzymes from Cynara cardunculus aqueous extracts, using as (optimal) conditions an enzyme/substrate ratio of 1.6% v/v, a pH of 5.2, a temperature of 55 degrees C and an incubation time of 7 h. The profiles of proteins and peptides were assessed by liquid chromatography and electrophoresis; ca. 87% of alpha-lactalbumin was hydrolyzed, but essentially no degradation of beta-lactoglobulin (beta-Lg) was observed. A bioactive peptide concentrate, its fraction below 3 kDa and a beta-Lg-rich fraction were obtained as final products, containing ca. 73, 43 and 91% w/w protein (on a total solid mass basis). All these fractions were low in lactose and salt, and their microbial loads were reduced. Said fractions are high added-value products, so they can be used as nutritional and functional ingredients-thus yielding an economically viable alternative for upgrade of whey. (C) 2012 Elsevier Ltd. All rights reserved.