Liu Yangjin, Jiang Fan, Du Chunwei, Li Mengqing, Leng Zhifu, Yu Xiuzhu, Du Shuang-Kui
Engineering Research Center of Grain and Oil Functionalized Processing in Universities of Shaanxi Province, College of Food Science and Engineering, Northwest A&F University, 22 Xinong Road, Xianyang 712100, China.
Foods. 2022 Jul 26;11(15):2223. doi: 10.3390/foods11152223.
Corn starch was dually modified using thermostable α-amylase and pullulanase to prepare resistant starch (RS). The concentration of starch liquid, the amount of added thermostable α-amylase, the duration of enzymatic hydrolysis and the amount of added pullulanase were optimized using RSM to increase RS content of the treated sample. The optimum pretreatment conditions were 15% starch liquid, 3 U/g thermostable α-amylase, 35 min of enzymatic hydrolysis and 8 U/g pullulanase. The maximum RS content of 10.75% was obtained, and this value was significantly higher than that of native corn starch. The degree of polymerization (DP) of the enzyme-modified starch decreased compared with that of native starch. The scanning electron microscopy (SEM) and differential scanning calorimetry (DSC) were performed to assess structural changes in native and pretreated starch. The effect of dual enzyme pretreatment on the structure and properties of corn starch was significant. Unlike the untreated one, the pretreated corn starch showed clear pores and cracks. Significant differences in RS contents and structural characterization between starch pretreated and untreated with dual enzymes demonstrated that the dual enzyme modification of corn was effective in enhancing RS contents.
使用耐热α-淀粉酶和支链淀粉酶对玉米淀粉进行双重改性以制备抗性淀粉（RS）。采用响应面法（RSM）优化淀粉液浓度、耐热α-淀粉酶添加量、酶解时间和支链淀粉酶添加量，以提高处理样品的RS含量。最佳预处理条件为：淀粉液浓度15%、耐热α-淀粉酶3 U/g、酶解35分钟、支链淀粉酶8 U/g。获得的最大RS含量为10.75%，该值显著高于天然玉米淀粉。与天然淀粉相比，酶改性淀粉的聚合度（DP）降低。进行扫描电子显微镜（SEM）和差示扫描量热法（DSC）以评估天然淀粉和预处理淀粉的结构变化。双酶预处理对玉米淀粉的结构和性质有显著影响。与未处理的淀粉不同，预处理的玉米淀粉显示出明显的孔隙和裂缝。双酶处理和未处理的淀粉之间RS含量和结构特征的显著差异表明，玉米的双酶改性有效地提高了RS含量。
