Preparation of high quality starch acetate under grinding and its influence mechanism

The goal of this study is to reveal mechanism of preparing high quality modified starch by advanced equipment in well-known modified starch enterprises. Corn starch was used as raw material to prepare starch acetate with low degree of substitution under grinding, and the effect of grinding on the quality of starch acetate was studied. The effects of grinding on structures and properties of native corn starch were investigated. The mechanochemical theory was used to analyze the influence mechanism of grinding on quality of starch acetate. The results showed that the reaction efficiency (RE) of starch acetate increased from 70.98% to 85.80% at 4 h of grinding, and other qualities (solubility and swelling power) also increased. However, RE and other qualities of starch acetate were very different at 12 and 20-60 h of grinding. The changes of structures and properties of native starch after grinding showed that grinding has a significant mechanochemical effect on corn starch granules. The models of starch molecules and granules were made to reveal the “secret” of these advanced equipment in well-known modified starch enterprises.