摘要
以藜麦麸皮为原料,经酶法制备可溶性膳食纤维(SDF)后,使用冷冻干燥、真空干燥、热风干燥和喷雾干燥方式干燥SDF,考察干燥方式对SDF结构形貌、理化性质及体外抗氧化活性的影响.结果表明:喷雾干燥的SDF持水力和持油力分别达到(3.95±0.14)g/g和(5.82±0.12)g/g,为4种干燥方式之最,其次是冷冻干燥;干燥方式对SDF官能团种类差异,但会导致吸收峰的强弱变化;冷冻干燥处理的SDF颗粒均匀,聚集体最小,存在大量孔隙;冷冻干燥处理的SDF中结合水较弱,不易流动水的结合强度较高和含量较低;冷冻干燥处理的SDF的DPPH·清除能力、ABTS+·清除能力、羟自由基清除能力最强,抗氧化活性最高,IC50分别达到1.88、1.38、8.18 mg/mL.冷冻干燥处理的SDF提高了抗氧化能力强和持水持油力,并提高其生物活性.
Abstract
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.
基金项目
国家重点研发计划子课题项目(2018YFE0206300)
NETL
NSTL
万方数据