采用中性蛋白酶(Neutral protease,NPT)对玉米醇溶蛋白(Zein)进行酶解改性,通过反溶剂法构建玉米醇溶蛋白酶解物(Corn protein hydrolysate,CPH)负载叶黄素(CPH-LUT)纳米体系,研究了其结构表征、体外抗氧化活性及溶解释放特性.结果 表明,最佳酶解条件为:酶用量2.7％,酶解时间60 min,酶解温度50℃,酶解pH 6.0,在此条件下,对叶黄素的包封率最高可达92.1％:制备的CPH-LUT纳米粒的平均粒径为173.7 nm,多分散系数为0.077,Zeta电位为-18.1 mV;抗氧化和体外释放实验表明,CPH-LUT纳米粒中叶黄素的溶解性以及抗氧化活性显著提高,叶黄素在胃液和肠液中的释放皆符合一级动力学模型,且CPH对叶黄素具有一定的缓释作用.NPT酶解改性的玉米蛋白可作为叶黄素类功能成分保护和输送的有效载体.
玉米粥的老化回生问题是影响玉米粥食用品质和营养价值的技术难题.文章以解决东北特色玉米大碴粥的老化回生问题为目标,考察酶解工艺对方便玉米大碴粥老化回生和胃肠消化的影响.采用α-淀粉酶限制性酶解工艺抑制玉米大碴粥的老化回生,通过单因素和正交试验优化得到了抑制玉米大碴粥老化回生的最佳酶解工艺条件:α-淀粉酶用量为0.06％、酶解温度95℃、酶解时间10 min,此酶解条件下玉米大碴粥的抗老度最高达到了79.6％.经酶解处理后的大碴粥老化回生现象显著改善,且有利于人体的消化和吸收.
The evolution of competition rules of football are analyzed.It is internal factors of affecting the evolution the football competition rules that development of technical and tactical soccer.Not only the revised rules reflect the technology and tactics of soccer,but also lead to development of a higher level of technology and tactics.Football competition rules changes also influenced by political,economic,cultural,scientific and technical and legal factors.The evolution of football competition rules has a certain social and times,improving the rule of law embodies sports and standardization.
