Stability Study of Fermented Milk using Lactiplantibacillus plantarum subsp. plantarum DAD-13 with Alpha Glucosidase Enzyme Inhibitory Activity on Simulated Gastrointestinal Digestion and Storage at Cold Temperature

Abstract

Fermented milk has bioactive peptides with alpha-glucosidase inhibitor capabilities. To be used widely, it must have stability when it stored and when it enters the human digestive tract. The purpose of this research was to understand the stability of alphaglucosidase inhibitory (AGI) activity of bioactive peptide from fermented milk on simulated gastrointestinal digestion and the stability during storage on cold temperature. Fermented milk was prepared by inoculating L. plantarum subsp. plantarum DAD-13 on sterilized milk for 18 h. The fermented milk was placed in simulated gastrointestinal digestion used consecutive pepsin for 3 h, bile salt and tripsin for 2h and tripsin for 8h. Determination of storage stability was carried out at cold temperature (4oC) for 30 days. Bioactive peptides simulated in the human digestive tract still had AGI abilities even though the values had decreased. The AGI activity of bioactive peptide of fermented milk decreased during digestion. AGI value decreased during storage but still had high inhibitory ability after 30 days (19,0126%). Thus, fermented milk could serve as an antihyperglycemic peptide source and alternative food for maintaining/reducing blood glucose.