[关键词]
[摘要]
玉米酶水解物是通过用商业酶水解玉米蛋白粉而制备。玉米蛋白粉的蛋白酶切位点被包被,酶解效率低,且酶解液呈棕黄色,以及不利于后续多肽的分离纯化影响感官效果。本研究对玉米蛋白粉预处理方法比较,确定了用加热和α淀粉酶对玉米蛋白粉进行预处理,提高酶解效率。用活性炭对玉米酶解液进行脱色处理,以脱色率和蛋白损失率为指标,确定最优脱色条件:脱色pH为5、脱色温度为40 ℃、活性炭用量为2%。并通过对脱色玉米肽抗氧化活性的考察,发现活性炭脱色后,玉米肽对DPPH清除率、ABTS清除率、ORAC清除率均有不同程度的下降,脱色前对DPPH的清除率为93.11%,对ABTS的清除率为1318.97 μmol TE/g,对ORAC的清除率为1192.39 μmol TE/g,脱色后对DPPH的清除率为33.19%,对ABTS的清除率为858.36 μmol TE/g,对ORAC的清除率为582.62 μmol TE/g,仍然保留较好的抗氧化活性。对脱色玉米肽进行ADH激活率和水解氨基酸测定发现,其对ADH的激活率为48.74%,并仍含有高含量的亮氨酸和丙氨酸,说明脱色玉米肽仍具有醒酒活性。
[Key word]
[Abstract]
Corn enzymatic hydrolysate was prepared via enzymatic hydrolysis of corn gluten meal using commercial enzymes. The sites for cleavage by a protease are coated, causing low efficiency of enzymatic hydrolysis, and brownish yellow colour in the corn enzymatic hydrolysate, (which is not conducive to the separation and purification of peptides and affects product sensory effect). This research compared the pretreatment methods of corn gluten meal, and it was determined that the corn gluten meal was pretreated by heating and α-amylase to improve the efficiency of subsequent enzymatic hydrolysis. The corn enzymatic hydrolysate was decolorized by activated carbon, and the optimum decolorization conditions were determined based on the decolorization rate and protein loss rate: decolorization pH was 5, decolorization temperature was 40 ℃, and activated carbon dosage was 2%. Through the investigation on the antioxidant activities of decolorized corn peptides, it was found that the DPPH, ABTS and ORAC radical scavenging rates decreased: they were 93.11%, 1318.97 μmol TE/g, and 1192.39 μmol TE/g, respectively, before decolorization, but were 33.19%, 858.36 μmol TE/g and 582.62 μmol TE/g, respectively, after decolorization (i.e. the decolorized corn peptides still retained significant antioxidant activity). The determination of the ADH activation rate and hydrolyzed amino acids of the decolorized corn peptide showed that the ADH activation rate was 48.74%, and the decolorized corn peptide contained high levels of leucine and alanine, indicating its sobering activity.
[中图分类号]
[基金项目]
国家重点研发计划项目重点专项(2017YFD0400200)