In vitro protein digestion of infant formula manufactured with β-casein-enriched whey

Abstract

A β-casein enriched whey produced from skim milk using a 2-step microfiltration process was used to manufacture a β-casein enriched infant formula (β-CN+ IF) with about 60% of β-CN in its casein fraction. Bringing the casein composition closer to that of human milk affected gelation properties and in vitro proteolysis in comparison with a control IF with the casein profile of cow milk. β-CN+ IF had a higher buffering capacity and produced a weaker gel during acidification but β-CN+ IF exhibited a lower degree of protein hydrolysis (DH) and slower β-CN proteolysis during in vitro gastric digestion. No marked differences were observed during the intestinal phase. β-CN bioactive peptides were more abundant in the β-CN+ IF digesta. Further investigations are needed to assess the impact of these differences on amino acid absorption, gastrointestinal hormone release and gut microbiota in babies fed with this formula composition.