碱消化法提纯大米淀粉的研究

蛋白质残留量是决定大米特性的主要因素,也是影响大米淀粉应用的关键因素。文中采用三因素正交实验设计,筛选了碱消化提纯大米淀粉的优化工艺条件:碱液浓度4g/L,提取时间4h,浆液浓度300g/L)。所得淀粉蛋白质残留量0·34%,低于Yamamoto法的0·42%;大米淀粉得率71%,比Yamamoto65%高6%。大米粉经碱消化去蛋白质提纯后,其膨润力和溶解度明显提高。

Isolation and Purification of Rice Starch by Alkali Digestion

The characteristic of starch is affected greatly by protein residual in starch. The purification of starch to remove the protein, therefore, is one of the main factors for its application. The objective of this study was to investigate optimum parameters for isolation and purification of rice starch with the method of alkali digestion. In a 3×3 factorial modeling experiment, the optimum conditions for alkali digestion were 0.4% (w/v) NaOH, 30% (w/v) starch slurry and 4 h digestive time. Under this condition, the protein residual in the purified starch was 0.34% (w/w), lower than Yamamoto's method, and the recovery of rice starch was 71%, 6% higher than that of Yamamoto (65%). Swelling power and solubility of the purified starch were greatly improved after removal of protein compared with the unpurified rice powder.