Comparison Of Phenolic Acids Component And Antioxitant Capacity Of Different Soymilk In Different Making Methods

Soymilk was made by four methods with fifteen variety soybean, then the total phenolic, total flavonoids, 16 kinds of phenolic acids and antioxidant activity were determined by Folin-Ciocalteu, colorimetric, RP-HPLC, DPPH, FRAP and ABTS methods. Using gallic acid, protocatechuic acid, 2,3,4-trihydroxybenzoic acid, protocatechualdehyde, p-hydroxybenzoic acid, gentisic acid, chlorogenic acid, vanillic acid, caffeic acid, syringic acid, vanillin, p-coumaric acid, syringaldehyde, ferulic acid, snapic acid, sallaylic acid, 16 kinds of phenolic acid monomers for HPLC to quantitative analysis. Using three different methods to detecte capacity of DPPH free radical scavenging, ferric reducing antioxidant capacity(FRAP) and ABTS radical scavenging assay for antioxidant capacity test analysis, and preparing the active ingredient with antioxidant capacity in different process of the different soybean milk.The result show that gallic acid, protocatechuic acid, 2,3,4-trihydroxybenzoic acid, protocatechualdehyde, p-hydroxybenzoic acid, syringic acid and vanillin as main ingredients in processed soymilk, gallic acid content is the most in the all, protocatechuic acid content is the second most in the all. The total phenolic, total flavonoids, phenolic acids content and antioxidant activity is significant different in(p<0.05) the four methods. The total phenolic, total flavonoids, phenolic acids content and antioxidant activity is significant different in(p<0.05) different kinds of soybean.In addition to measured by DPPH radical scavenging capacity in the dry process of soybean milk, total phenolic content and DPPH free radical scavenging, ferric reducing antioxidant capacity(FRAP) and ABTS radical scavenging assay is linear correlation; In addition to measured by DPPH free radical scavenging and ferric reducing antioxidant capacity(FRAP) in dry cooked pulp process of soybean milk, phenolic acid content and DPPH free radical scavenging, ferric reducing antioxidant capacity(FRAP) and ABTS radical scavenging assay is linear correlation; And total flavonoids content and antioxidant activity are not had good linear relationship.