摘要
为提高麦胚储藏稳定性,采用过热蒸汽处理麦胚并优化处理工艺,以达到较好的灭酶效果的同时尽量减少处理后麦胚色泽的变化以及营养物质的损失.通过单因素实验研究处理温度(170～210 ℃)、处理时间(10～50 s)、麦胚水质量分数(13％～21％)对处理后麦胚色泽、酶活、营养组分(黄酮含量、多酚含量、还原糖含量、游离氨基酸含量)和抗氧化的影响.在单因素实验的基础上对3个实验因素进行正交优化,以麦胚色差(ΔE)、灭酶率、黄酮含量、多酚含量和还原糖含量为评分指标进行综合评分.结果表明过热蒸汽处理最优条件为210℃、处理时间为30 s、麦胚水质量分数为15％,在该条件下处理后的麦胚色差为7.30、脂肪酶灭活率为60.94％、脂肪氧化酶灭活率为85.00％,黄酮含量为1 615.64 mg RT/100 g DW、多酚含量为441.77 mg GAE/100 g DW、DPPH自由基清除率为78.82％、ABTS+自由基清除率为70.64％,还原糖含量为55.95 mg/g,综合评分达到0.751 2分;在40℃条件下加速储藏实验研究表明,处理后的麦胚储藏30 d脂肪酸值从159.74 mg/100 g上升到354.89 mg/100 g,而未处理组麦胚储藏30 d脂肪酸值从172.27 mg/100 g上升到624.00 mg/100 g;这说明过热蒸汽处理能大幅延缓麦胚氧化酸败的速率.
Abstract
In order to improve the stability of wheat germ,wheat germ was treated with superheated steam and the treatment process was optimized to achieve better enzyme inactivation effect and minimize the color change and nutrients loss of wheat germ after treatment.The effects of processing temperature(170-210℃),processing time(10-50 s),and the moisture content of wheat germ(13％-21％)on the color,enzyme activity,and nutritional components(flavonoid content,polyphenol content,reducing sugar content,and free amino acid content)and an-tioxidation of treated wheat germ were studied through single factor experiments.On the basis of single factor exper-iments,the orthogonal optimization of the three test factors was carried out,and the wheat germ color difference(ΔE),enzyme inactivation rate,flavonoid content,polyphenol content and reducing sugar content were used as scoring indexes for comprehensive scoring.The results indicated that the optimal conditions for steam treatment were 210 ℃ for 30 seconds,.the moisture content of wheat germ at 15％;under these conditions,the color differ-ence of wheat germ was 7.30,the inactivation rate of lipase was 60.94％,the inactivation rate of lipoxygenase was 85.00％,the content of flavonoids was 1 615.64 mg RT/100 g DW,the content of polyphenols was 441.77 mg GAE/100 g DW,the scavenging rate of DPPH radicals was 78.82％,the scavenging rate of ABTS radicals was 70.64％,the content of reducing sugars was 55.95 mg/g,and the comprehensive score was 0.751 2 points;the accelerated storage experiment at 40 ℃ revealed that the fatty acid value of wheat germ in the treated group increased from 159.74 mg/100 g to 354.89 mg/100 g after 30 days of storage,while the fatty acid value of wheat germ in the untreated group increased from 172.27 mg/100 g to 624.00 mg/100 g after 30 days of stor-age;this indicated that superheated steam treatment could significantly delay the oxidative rancidity rate of wheat germ.
基金项目
国家"十四五"重点研发计划项目(2021YFD2100901)
NETL
NSTL
万方数据