School of Tea and Food Technology, Anhui Agricultural University, China.
School of Tea and Food Technology, Anhui Agricultural University, China.
Int J Biol Macromol. 2017 Dec;105(Pt 1):317-327. doi: 10.1016/j.ijbiomac.2017.07.044. Epub 2017 Jul 10.
Optimization of the preparation of hydroxypropylated, phosphorylated and hydroxypropyl-phosphorylated glutinous rice starch was performed using a response surface methodology comprising three variables at three levels. Multi-linear regression was used to fit the degree of substitution and molar substitution against. Optimal reaction conditions were 9h, 42°C, 10% (hydroxypropylated), 148min, 150°C, 7% (phosphorylated) and 95min, 140°C, 7.8% (hydroxypropyl-phosphorylated). For hydroxypropylated, predicted optimal and experimental molar substitution values were found to be identical: 0.20. Both the phosphorylated and hydroxypropyl-phosphorylated, the predicted optimal and experimental degree of substitution values was 0.02. Static rheological analysis revealed a pseudoplastic nature for native and modified starches and an increase in apparent viscosity following modification. Dynamic rheological analysis indicated an entanglement network system for native glutinous rice starch suspension, but weak elastic gel-like structure for modified starches as the storage modulus (G') exceeded the loss modulus (G"). Additionally, chemical modification improved the freeze-thaw stability, swelling power, solubility and paste clarity.
采用三因素三水平响应面法优化羟丙基化、磷酸化和羟丙基磷酸化糯米淀粉的制备条件。采用多元线性回归拟合取代度和摩尔取代度。最佳反应条件为：9h、42°C、10%（羟丙基化）、148min、150°C、7%（磷酸化）和 95min、140°C、7.8%（羟丙基磷酸化）。对于羟丙基化，预测的最佳摩尔取代度和实验值相同：0.20。对于磷酸化和羟丙基磷酸化，预测的最佳取代度和实验值均为 0.02。静态流变分析表明，天然淀粉和改性淀粉均具有假塑性，且改性后表观黏度增加。动态流变分析表明，天然糯米淀粉悬浮液为缠结网络体系，而改性淀粉为弱弹性凝胶状结构，因为储能模量（G'）超过损耗模量（G"）。此外，化学改性提高了冻融稳定性、溶胀能力、溶解度和糊液透明度。
