过热蒸汽灭酶处理对青稞籽粒理化特性和稳定性影响OA

Highland barley is rich in β-glucan and other nutrients,possessing a high health value.However,it is prone to rancidity and deterioration during storage,which limited its application in the food industry.In this study,highland barley was stabilized by high-temperature and short-time superheated steam,and the effects of different treatment temperatures on the activities of endogenous enzymes,β-glucan content,starch digestion and gelatinization characteristics,microstructure and storage stability of highland barley were studied.The results showed that superheated steam treatment significantly reduced the activities of lipase and peroxidase in highland barley grains.After the treatment at 190℃for 10 s,the residual activities of these two enzymes were 24.70%and 14.76%,respectively.The content of β-glucan decreased(in the range from 12.31%to 16.90%)after treatments at different temperatures.Furthermore,superheated steam treatment also significantly altered the in vitro digestion and gelatinization properties of highland barley starch,with the contents of slowly digestible starch(55.14%)and resistant starch(32.35%)and peak viscosity decreasing,whilst the rapidly digestible starch content(239.39%)and gelatinization temperature increasing(1.80%).Superheated steam had minimal impact on the microstructure of highland barley grains when the treatment temperature was below 180℃.After three months of storage at 37℃,the acid values of the superheated steam treatment group were all lower than that of the control group,and the increment of acid value was reduced by half,.In general,superheated steam treatment effectively reduced the endogenous enzyme activities and improved the storage stability of highland barley grains,with the superheated steam treatment at 180℃for 10 s resulting in the best quality.This study provides a theoretical basis for the application of highland barley in the food field.