Studies on the Antioxidation Activity of Almond Protein Hydrolysates

Dilute homogenate of almond dregs was prepared after extraction of almond oil and elimination of organic solvent.The hydroxyl free radical scavenging activity (SA)of the almond dregs dilute homogenate hydrolysate,which was produced by hydrolysis with four kinds of different protease,was investigated by examining the absorbance with 722 UV-Spectrometer.The result revealed that the radical scavenging activity of the hydrolysate increased significantly after the almond dregs homogenate was hydrolyzed with different enzyme.The hydrolysates digested with alkali protease showed the highest scavenging activity among the four kinds of protease.The most suitable hydrolysis parameters of alkali protease,determined through the orthogonal examination based on the single factor experiment,include substrate protein concentration 2.5 % ,enzyme/substrate ratio 20 000 U/g,temperature 70 ℃,pH=9 and time duration 0.5 h,with the scavenging activity 63 % of hydroxyl free radical.The variance analysis of affecting factor of scavenging activity on hydroxyl free radical indicates that temperature,original pH,substrate concentration and enzyme/ substrate ratio all have great effect on antioxidation and has significant difference within the range of experiment design.