为延长核桃仁货架期,提高核桃仁储藏品质.以去皮核桃仁为原料,利用复配蛋白酶(胰酶)酶解核桃仁实现原位富集抗氧化肽,采用单因素实验分别研究了底物质量分数、酶质量分数、水解温度、水解时间对水解液抗氧化活性的影响.在此基础上,采用正交实验确定最优水解工艺为:酶质量分数12％、底物质量分数40％、水解温度45℃、水解时间20 min.萃取酶解处理的核桃仁(样品组)和未处理的核桃仁(空白对照组)油脂测定其氧化诱导时间,将样品组和空白对照组用铝袋分装在60 ℃烘箱内加速氧化.结果表明,样品组具有更长的氧化诱导时间及Q10指数,其氧化自由能从59.896 kJ/mol上升到78.103 kJ/mol;加速氧化过程对照组过氧化值始终高于样品组,以过氧化值为指标结合油脂氧化规律得到在20℃下样品组货架期相对于对照组延长了 68 d.
Optimization of In-situ Hydrolysis Process and Oxidation Stability of Walnut Kernels
To extend the shelf life of walnut kernels and improve their storage quality.The effects of substrate mass fraction,enzyme mass fraction,hydrolysis temperature and hydrolysis time on the antioxidant activity of the hy-drolysate were investigated in a single-factor experiment.The optimal hydrolysis process was determined based on orthogonal experiments:12％enzyme mass fraction,40％substrate mass fraction,45 ℃ hydrolysis temperature and 20 min hydrolysis time.Testing of enzymatically treated walnut kernels(sample group)and untreated walnut kernels(blank control group)to determine their oxidation induction time.The results indicated that the sample group had a longer oxidation induction time and Q10 index,and its free energy of oxidation increased from 59.896 kJ/mol to 78.103 kJ/mol;the peroxide value of the control group was always higher than that of the sample group during the accelerated oxidation process.The shelf life of the sample group was effectively extended by 68 days at 20 ℃.
walnut kernelsenzymatic hydrolysis optimizationantioxidant peptideaccelerated oxidationoxida-tion stabilityshelf life prediction
万方数据
维普
