氧化-乙酰化甘薯淀粉制备及性质测定

Preparation and Properties of Oxidized Acetylation Sweet Potato Starch

以漂白甘薯淀粉为原料,对氧化-乙酰化甘薯淀粉的制备工艺进行了研究,并对其部分物理化学性质进行了研究。通过单因素和正交试验得出制备氧化-乙酰化甘薯淀粉最佳工艺条件:乙酸酐添加量为为淀粉乳体积的8%,反应pH为7.0,反应时间1.5 h,通过以上制备条件可得取代度为0.029的氧化-乙酰化甘薯淀粉。酯化改性后的甘薯淀粉透光率与凝沉性大大改善,冻融稳定性、抗老化性、酸碱稳定性、溶解度、白度都得到了提高。

The application of natural sweet potato starch was limited due to the thermal instability of the pastes, weak acid and alkali resistance and poor freeze-thaw stability. On the basis of the above reasons, the bleached sweet potato starch was used as the raw material to carry out the preparation of the oxidized acetylated sweet potato starch. And the physical and chemical properties were also studied. The single faetor and orthogonal experiments resulted in the optimum conditions of preparation of the oxidized acetylated sweet potato starch as： addition of 8% acetic anhydride at pH 7.0 for 1.5 h. By this way, the substitution degree of oxidized acetylated sweet potato starch might reach as much as 0.029. The light transmission rate and the retrogradation properties, as well as the freeze-thaw stability, the anti-aging ability, the acid-base stability, the solubility and the whiteness were all improved in the esterification modified sweet potato starch.