Abstract:In this study，β-amylase combined with α-glucosidase to increase the slow-digesting starch content and its in vitro hypoglycemic activity of germinated black barley flour was studied.The optimal process conditions were determined by single factor test，in vitro simulated digestion method and Box-Behnken response surface test，and their in vitro hypoglycemic activity was evaluated by the determination of the inhibition rate of αamylase and α-glucosidase.The results showed that the optimal enzymatic hydrolysis conditions for the synergistic increase of slowly-digestible starch content of barley were as follows:β-amylase and α-glucosidase addition of 150 U/g barley powder，enzymatic hydrolysis time of 8 h，enzymatic hydrolysis temperature of 50 ℃，and concentration of highland barley powder 10%.Under these conditions，the slowly-digestible starch content of highland barley reached the highest of 33.62%.In the in vitro hypoglycemic activity assay，compared with the original powder，the inhibition rate of α-amylase and α-glucosidase of enzyme-modified barley powder increased by 62.97%and 52.46%，indicating that the in vitro hypoglycemic activity of enzymatic hydrolyzed powder was significantly improved.