湿热预处理对酸解淀粉纳米晶制备的影响

Effects of Heat-Moisture Pre-treatment on Preparation of Acid-Hydrolyzed Starch Nanocrystals

将湿热处理(HMT)作为一种预处理手段,对HMT淀粉进行特定高温短时间的硫酸酸解并研究其对淀粉纳米晶(SNC)制备过程的影响。湿热处理(HMT)后淀粉的热稳定性、抗酸解性得到增加。对其水解率、X射线衍射特性、粒径分布特性、热特性和外观形貌特性等研究后发现:湿热处理淀粉在69℃时用硫酸酸解30 min即可制备SNC,产率为11.6%,相对结晶度为43%,平均粒径为300 nm。制得的SNC呈不规则形状且干燥过程中发生团聚;69℃酸解湿热处理淀粉不仅可以提高酸解效率,还赋予SNC一定的耐热性,可以拓宽SNC的温度使用范围。

The effect of heat-moisture treatment(HMT)on the preparation of starch nanocrystal(SNC)was analyzed in this study.The SNC was prepared by hydrolyzing HMT corn starches with H2SO4 at predetermined relatively high temperatures.The hydrolysis process was maintained at high temperatures for maximizing the hydrolysis rate,which also improved the heat sensitivity of the final SNC product.The particle size distribution(PSD),XRD,and SEM were also investigated.The results indicated that the SNC could be well prepared at 69℃within 30 min;the yield of which was 11.6%.SNC products generated agglomeration during the drying process and the crystallinity of which was 43%.The acid hydrolysis of HMT starches at 69oC could not only improve the hydrolysis efficiency but also endow the SNC with preferable thermostable properties,which was good for broadening the temperature range of SNC.