Ren Fei, Liu Xingkai, Xie Fengwei, Wang Shujun
State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science & Technology, Tianjin 300457, China; School of Food Science and Technology, Tianjin University of Science & Technology, 300457, China.
Department of Chemical Engineering, University of Bath, Bath BA2 7AY, United Kingdom.
Carbohydr Polym. 2024 Dec 1;345:122560. doi: 10.1016/j.carbpol.2024.122560. Epub 2024 Aug 2.
This work studied the phase transition and gel properties of cassava starch in aqueous choline acetate ([Ch][OAc]) solution at different [Ch][OAc]:water weight ratios. The paste viscosity and gel strength followed a similar pattern to the starch phase transition temperature, increasing at a 2:3 [Ch][OAc]:water ratio and then decreasing at 3:2 and 4:1 ratios. However, the mobility of free water in the starch gel decreased as the [Ch][OAc]:water ratio increased. At the same [Ch][OAc]:water ratios, acetylated cassava starch (ACS) underwent phase transition more easily than native cassava starch (NCS), leading to greater granule destruction. Nevertheless, ACS gels displayed more viscous-dominated rheological behavior, lower paste viscosity, viscoelasticity, and weaker water-holding capacity (WHC) than NCS gels. In contrast, cross-linked cassava starch (CCS) gels had higher paste viscosity, gel viscoelasticity, and WHC. However, at a 4:1 [Ch][OAc]:water ratio, the viscoelasticity of CCS gel was lower than NCS gel, and the differences in WHC were minimal, likely due to the incomplete phase transition of especially CCS under this condition. Our findings show that starch chemical modification significantly affects phase transition behavior and gel properties in [Ch][OAc]:water mixtures, with outcomes influenced by the viscosity of the aqueous [Ch][OAc] solution and the interaction between [Ch][OAc] and water.
本研究考察了木薯淀粉在不同醋酸胆碱（[Ch][OAc]）与水重量比的醋酸胆碱水溶液中的相变及凝胶特性。糊化粘度和凝胶强度与淀粉相变温度呈现相似的规律，在[Ch][OAc]与水的比例为2:3时升高，然后在3:2和4:1的比例下降低。然而，随着[Ch][OAc]与水比例的增加，淀粉凝胶中自由水的流动性降低。在相同的[Ch][OAc]与水比例下，乙酰化木薯淀粉（ACS）比天然木薯淀粉（NCS）更容易发生相变，导致颗粒破坏更严重。尽管如此，与NCS凝胶相比，ACS凝胶表现出更多以粘性为主导的流变行为、更低的糊化粘度、粘弹性和较弱的持水能力（WHC）。相比之下，交联木薯淀粉（CCS）凝胶具有更高的糊化粘度、凝胶粘弹性和WHC。然而，在[Ch][OAc]与水比例为4:1时，CCS凝胶的粘弹性低于NCS凝胶，并且WHC的差异最小，这可能是由于在此条件下特别是CCS的相变不完全所致。我们的研究结果表明，淀粉化学改性显著影响[Ch][OAc]与水混合物中的相变行为和凝胶特性，其结果受醋酸胆碱水溶液的粘度以及[Ch][OAc]与水之间相互作用的影响。
