超声预处理对玉米蛋白可酶解性的影响  

Effects of Ultrasound Pretreatment on the Enzymatic Hydrolysis of Corn Gluten Meal

作　　者：金建[1] 马海乐[1] 曲文娟[1] 周存山[1] 罗敏[1] 何荣海[1] 洪晨[1] 翁龙梅 

机构地区：[1]江苏大学食品与生物工程学院江苏省农产品物理加工重点实验室,镇江212013

出　　处：《中国粮油学报》2015年第11期58-64,共7页Journal of the Chinese Cereals and Oils Association

基　　金：863计划(2013AA102203);国家自然科学基金(31301423);江苏省产学研前瞻性研究(BY2013065-01);江苏省普通高校研究生科研创新计划(CXZZ13_0695)

摘　　要：旨在采用超声预处理改善玉米蛋白的酶解性，研究了超声频率模式（单频、双频、定频和扫频）及频率参数对玉米蛋白酶解水解度及溶解率的影响，采用高效尺寸排阻色谱法对酶解液的分子质量分布进行了表征。研究发现，（68±2）kHz／（28±2）kHz双频扫频为最佳超声频率模式，优化试验获得超声预处理的最佳工作参数为：超声温度30℃、料液比1：20（g／mL）、超声处理时间40min、扫频周期500ms、超声功率密度80W／L、脉冲超声的工作时间10S和间歇时间3S。在最佳超声频率模式及工作参数预处理的条件下，水解度和蛋白溶解率分别为23．6％和75．2％，较对照组（未经超声处理）分别提高了39．4％和54．7％，且酶解液具有更窄的分子质量分布范围。这表明超声预处理能促进玉米蛋白向多肽转化，尤其有利于分子质量为200～1000u的玉米蛋白肽的形成。To study the effects of ultrasound pretreatment on the degree of hydrolysis （DH） and dissolution ratio （DR） of corn gluten meal （CGM）. The ultrasonic frequency mode （ single frequency, dual - frequency, fixed fre- quency and sweep frequency） , and the operating parameters of ultrasound on the enzymatic hydrolysis of CGM were optimized. The High perfermance size exclusion chromatography （HPSEC） was utilized to characterize the molecular weight （MW） distribution of hydrolysate. The results showed that the optimal condition of ultrasonic frequency mode was （ 68 -＋ 2 ） kHz/（ 28 _＋ 2） kHz ; the optimum operating pretreatment parameters conditions were temperature of ul- trasonic condition at 30 ℃, ultrasonic treatment time of 40 min, pulsed on - time 10 s on and off - time 3 s off, cycle time of the sweep frequency 500 ms, and ultrasonic power density 80 W/L. The pretreated CGM was subsequently hydrolyzed by Alcalase 2.4L with an enzyme/substance ratio of 4 740 U/g, temperature at 50 ℃, pH 9.0 and 60 min. Under the optimum condition of ultrasonic frequency mode and operating parameters, the DH and DR of CGMwere as 23.6% and 75.2%, which were 39.4% and 54.7% higher than that of the control respectively. The results indicated that the ultrasonic pretreatment could have a facilitative effect on the enzymatic hydrolysis of CGM, which will promote the conversion of protein to peptides, especially the peptides with a MW of 200 -1 000 u.

关 键 词：超声预处理 玉米蛋白 频率模式 高效尺寸排阻色谱分子质量分布 

分 类 号：TS201.1[轻工技术与工程—食品科学]