[i]In vitro[/i] Digestibility of Goat Milk Kefir with New Standardised Static Digestion Method (INFOGEST Cost Action) and Bioactivities of the Resultant Peptides
Résumé
Hydrolyses degree of goat milk and kefir during simulated gastrointestinal digestion system and some bioactivities of resultant peptides after fermentation and digestion were studied. Static in vitro digestion method by the COST FA1005 Action INFOGEST was used and goat milk and kefir were partially hydrolyzed during gastric phase and had above 80% hydrolysis after duodenal digestion. There were not any differences between digestibility of goat milk and kefir (p>0.05). Goat milk and kefir displayed about 7-fold antioxidant activity after digestion (p<0.05). Fermentation showed no effect on calcium-binding capacity of the samples (p>0.05), however after in vitro digestion calcium-binding capacity of the goat milk and kefir increased 2 and 5 fold, respectively (p<0.05). Digested goat milk and kefir showed a higher dose-dependent inhibitory effect on α-amylase comparing undigested samples (p<0.05). α-glucosidase inhibitory activities and in vitro bile acid-binding capacities of the samples were not determined at studied concentrations.