CAJ | 학술논문

为了研究玉米蛋白粉的酶解关键技术和利用电子束辐照技术辅助提高玉米蛋白粉的酶解效果，该研究以蛋白质质量分数为79.4%的玉米蛋白粉为原料，以水解度（degree of hydrolysis，DH）和1,1-二苯基-2-三硝基苯肼（1,1-diphenyl-2-picryl-hydrazyl, DPPH）清除率为衡量指标，借助单因素和响应面试验设计方法，在优选碱性蛋白酶可控酶解制备玉米抗氧化肽的最佳工艺参数基础上，研究了不同辐照剂量的电子束辐照处理对玉米蛋白粉酶解效果的影响，并利用场发射扫描电镜检测技术分析电子束辐照前后玉米蛋白粉表面形态的变化。研究发现：当碱性蛋白酶的酶解温度为50℃、酶解 pH 值为8.6、酶与底物浓度比为9.13%时，玉米蛋白粉的水解度可达40.26%±0.23%；所制备的玉米抗氧化肽的DPPH清除率为70.74%±0.41%；若采用辐照剂量为3.24 kGy进行电子束辐照处理玉米蛋白粉时，则其水解度可达到49.17%±0.42%，其DPPH清除率可达73.03%±1.02%；经场发射扫描电镜检测分析得知，被辐照处理后的玉米蛋白粉表面凹凸程度增加，完整性下降。研究结果可为玉米精深加工产业和玉米抗氧化肽的深入研究提供理论参考。
위료연구옥미단백분적매해관건기술화이용전자속복조기술보조제고옥미단백분적매해효과，해연구이단백질질량분수위79.4%적옥미단백분위원료，이수해도（degree of hydrolysis，DH）화1,1-이분기-2-삼초기분정（1,1-diphenyl-2-picryl-hydrazyl, DPPH）청제솔위형량지표，차조단인소화향응면시험설계방법，재우선감성단백매가공매해제비옥미항양화태적최가공예삼수기출상，연구료불동복조제량적전자속복조처리대옥미단백분매해효과적영향，병이용장발사소묘전경검측기술분석전자속복조전후옥미단백분표면형태적변화。연구발현：당감성단백매적매해온도위50℃、매해 pH 치위8.6、매여저물농도비위9.13%시，옥미단백분적수해도가체40.26%±0.23%；소제비적옥미항양화태적DPPH청제솔위70.74%±0.41%；약채용복조제량위3.24 kGy진행전자속복조처리옥미단백분시，칙기수해도가체도49.17%±0.42%，기DPPH청제솔가체73.03%±1.02%；경장발사소묘전경검측분석득지，피복조처리후적옥미단백분표면요철정도증가，완정성하강。연구결과가위옥미정심가공산업화옥미항양화태적심입연구제공이론삼고。
In this study, the key technology of enzymatic hydrolysis of corn protein powder and the improvement of enzyme effectiveness with the electron beam irradiation technology were researched. Corn gluten meal (mass fraction of 79.4%) was used as raw material. Alacalase was used to hydrolyze corn gluten meal, and degree of hydrolysis (DH) and 1,1-diphenyl-2-picryl-hydrazyl (DPPH) inhibition were used as testing indexes. In order to develop and optimize conditions for the enzymatic hydrolysis reaction, we investigated three variables:enzyme solution temperature, pH value, and ratio of enzyme to substrate. One-factor-at-a-time (OFAT) and response surface metrology (RSM) experiment were used to optimize the conditions for hydrolysis. Based on the optimized results, the influences of different electron beam irradiation doses on the DH and DPPH inhibition of corn gluten meal were studied. The irradiation dose rate was 1.08 kGy/s, the irradiation time were 0, 1, 2, 3, 4, 5, and 6 seconds, the irradiation doses were 0, 1.08, 2.16, 3.24, 4.32, 5.4 and 6.48 kGy. And the microcosmic surface features of corn gluten meal in three irradiation doses (0, 3.24 and 6.48 kGy) by electron beam irradiation treatment were analyzed by scanning electron microscope (SEM). The results of OFAT showed that, the DH reached the highest value 37.89%±2.89% when the enzyme solution temperature was 60℃, and the DPPH inhibition reached the highest value 58.45%±2.07%when the temperature was 40℃. The DH reached the highest value 40.81%±0.8%when the pH value was 9, and the DPPH inhibition reached the highest value 72.93%±0.96%when the pH value was 6. The DH reached the highest value 38.31%±0.8%when the ratio of enzyme to substrate was 12%, and the DPPH inhibition reached the highest value 67.07%±0.83% when the ratio of enzyme to substrate was 2%. The results of RSM test showed that, the optimized parameters of enzyme hydrolysis were:enzyme solution temperature was 50℃, pH value was 8.6, ratio of enzyme to substrate was 9.13%. On these conditions, the DH value of corn gluten meal was 40.26%±0.23%, and the DPPH inhibition of corn antioxidative peptides (CPS) was 70.74%±0.41%. In the electron beam irradiation experiment, the optimize irradiation dose was 3.24 kGy, with the DH of 49.17%±0.42%and DPPH inhibition of 73.03%± 1.02%. The SEM results showed that compared with the blank sample, the smoothness of corn gluten meal powder with irradiation decreased, and the specific surface area was increased. The results provide a reference for corn processing industry and also for further studies on corn antioxidant peptides.