酶解-挤出复合工艺对高直链淀粉材料制备和性质的影响  

Effects of Enzyme-Extrusion Composite Technology on the Preparation and Properties of High Amylose Starch-based Materials

作　　者：刘鹏[1] 周福金 刘晓彤 陈颖超[1] LIU Peng;ZHOU Fu-jin;LIU Xiao-tong;CHEN Ying-chao(School of Chemistry and Chemical Engineering, Guangzhou University, Guangzhou 510006, China)

机构地区：[1]广州大学化学化工学院,广东广州510006

出　　处：《现代食品科技》2018年第5期143-147,31,共6页Modern Food Science and Technology

基　　金：国家自然科学基金课题(21106023);广州市科技计划项目珠江科技新星专项(201610010019);广州市属高校科技计划项目(1201410965);广州大学大学生创新训练项目

摘　　要：以高直链淀粉为原料制备的淀粉基材料力学性质优良。但其熔融流变性差,挤出加工能耗高。本论文采用酶解-挤出复合工艺,考察了耐高温α淀粉酶对挤出环境的耐受性,以及酶加入量、挤出时间等参数对材料制备和性质的影响。结果表明,耐高温α淀粉酶在密炼机的挤出环境中依然有酶活力,能够促进淀粉颗粒的结构相变,从而降低单位机械能耗,缩短加工时间。具体而言,在0.25%的酶加入量下(淀粉干基重量),G50淀粉挤出加工的单位能耗下降了21%。但酶解也会造成分子链的降解,削弱材料性质。与空白材料相比,经酶解-挤出工艺的淀粉基材料,其拉伸强度降低了33%,断裂伸长率减少了83%。另一方面,耐高温α淀粉酶对G80淀粉挤出加工的影响不显著。上述结果表明,可以利用酶解-挤出复合工艺降低生产能耗,缩短加工时间,且酶解会提高淀粉的活性位点和反应效率,有利于淀粉的反应挤出。The materials prepared by high amylose starch have good properties and applications. But the melt viscosity of high amylose starch is poor and extrusion processing energy consumption is high. In this paper, the tolerance of enzyme in extrusion environment and the effects of the addition and the extrusion time on the mechanical energy and the mechanical properties of materials were investigated used the enzyme-extrusion composite technology. The results showed that the thermostable α-amylase could maintain enzyme activity in the extrusion environment under high temperature, high pressure, and high shearing force. Besides, they could improve the phase transition of high amylose granules, promote the extrusion processing, and then reduce the extrusion time and decrease the mechanical energy. Specifically, the specific mechanical energy of G50 high amylose starch could decrease by 21 %, and the tensile strength and elongation of materials were also reduced by 33 % and 83%, respectively when the addition of enzyme was only 0.25 % of starch（dry weight）... On the other hand, the thermostable α-amylase had no significant effect on the extrusion of G80 high amylose starch. These results illustrated that the synergistic effects of enzyme-extrusion composite technology could conserve the extrusion processing energy of high amylose starch and reduce extrusion time. Moreover, enzymatic hydrolysis could increase the active site and reaction efficiency of starch, which was beneficial to the starch reaction extrusion.

关 键 词：淀粉基材料 高直链淀粉 酶解-挤出复合工艺 单位机械能耗 力学性质 

分 类 号：TS235[轻工技术与工程—粮食、油脂及植物蛋白工程]