Soluble dietary fiber(SDF)was prepared from quinoa bran by enzymatic method,and then dried by freeze drying,vacuum drying,hot air drying and spray drying.The effects of drying methods on the structure,physi-cochemical properties and in vitro antioxidant activity of SDF were investigated.The results indicated that the water holding capacity and oil holding capacity of spray-dried SDF were(3.95±0.14)g/g and(5.82±0.12)g/g,re-spectively,the highest among the four drying methods,followed by freeze-drying.The drying method had different types of SDF functional groups,but it would lead to changes in the strength of the absorption peak;the freeze-dried SDF particles were uniform,the aggregates were the smallest,and there were a large number of pores.The bound water in SDF treated by freeze-drying was weak,and the binding strength of immobilized water was high,and the content was low.The DPPH free radical scavenging ability,ABTS+free radical scavenging ability and hydroxyl radi-cal scavenging ability of SDF treated by freeze-drying were the strongest,and the antioxidant activity was the high-est.The IC50 were 1.88,1.38 and 8.18 mg/mL,respectively.In summary,freeze-dried SDF improved its antioxi-dant capacity,water and oil holding capacity,and improved its biological activity.
NETL
NSTL
万方数据
