Cross - linking and esterifying starch of mechanical activated cassava starch was prepared by using mechanical activated cassava starch as raw material, and using sodium trimetaphosophate for cross - linking agent and acetic anhydride for acetification, which its synthesis route prepared by continual reactions in one - step synthesis way. The effects of reaction temerature, cross - linking agent and esterifying agent dosage, pH value of cross — linking and esterifying and cross - linking time on the cold viscosity of cross - linking and esterifying starch paste were investigated respectively, and the physical and chemical Parameters and structure of the cross - linking and esterifying starch with mechanical activated cassava starch and cross - linking and esterifying starch with raw cassava starch were studied. The results indicated that the above reaction conditions were all found to affect the preparation of cross - linking and esterifying mechanical activated cassava starch. Under the reaction temperature 40℃ ,1.0% amounts of sodium trimetaphosphate,crosslinking pH value 10.0,crosslinking time 2. 0 h,acetic anhydride amount 0. 5 mL,esterifying pH value 9.0, esterifying time 60 min, the cold viscosity of cross - linking and esterifying starch paste of mechanical activated cassava was enhanced from 847 mPa. S of cassava starch to 3 225 mPa. S, and the stability, acidity - resistance, staling resistance of the viscosity of starch paste were significantly improved. Cross - linking and esterifying composite modified was propitious to formation of V type crystal starch.%以机械活化木薯淀粉为原料,三偏磷酸钠为交联剂,醋酸酐为酯化剂,采用一步连续法制备机械活化木薯交联酯化淀粉,考察反应温度、交联剂用量、交联pH、交联时间、酯化剂用量、酯化pH、酯化时间等因素对交联酯化淀粉糊冷黏度的影响,并与原木薯淀粉合成的交联酯化淀粉进行比较,研究了产物的理化特性和结构.结果表明,各因素对机械活化木薯淀粉的交联酯化反应均有影响.对于机械活化1.0h的木薯淀粉,在反应温度40C、三偏磷酸钠1.0％、交联pH 10.0、交联时间2.0h、醋酸酐用量0.5mL、酯化pH 9.0、酯化时间60 min的条件下,所制备的机械活化木薯交联酯化淀粉糊的冷黏度由机械活化淀粉的847 mPa·s提高到3 225 mPa·s,淀粉糊液黏度的稳定性、抗酸性、抗老化性显著提高.交联酯化复合变性有利于形成淀粉的Ⅴ型结构.
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