Kou Tingting, Song Jun, Liu Mouquan, Fang Guihong
College of Food Engineering and Biotechnology, Hanshan Normal University, Chaozhou 521041, China.
Center for Biomedical Optics and Photonics (CBOP) & College of Physics and Optoelectronic Engineering, Key Laboratory of Optoelectronic Devices and Systems, Shenzhen University, Shenzhen 518060, China.
Polymers (Basel). 2022 Jul 15;14(14):2870. doi: 10.3390/polym14142870.
Starches from normal maize (NM), normal potato (NP), waxy maize (WM), and waxy potato (WP) were cross-linked with seven different concentrations (0.01, 0.05, 0.1, 0.5, 1, 5, 10%) of sodium trimetaphosphate and sodium tripolyphosphate. The use of low-amylose WM and WP as well as A-crystalline maize and B-crystalline potato starches can determine the influence of the amylose content and crystallinity pattern on the cross-linking of starches. The results showed that the viscosity of the cross-linked starch (CLs) first increased and then deceased, and finally no viscosity was detected; WM showed no viscosity at 5% and NP at 1%. In addition, the viscosity of NM first increased and then became undetectable at 0.5%. Strikingly, the WP developed viscosity even at a 10% reagent level (RL), and it developed the highest viscosity of all samples at 1%. The starch-iodine method was a facile and high-performance method for the characterization of the cross-linking degree (CL%), having been applied to normal starches, because the increase in the CL% resulted in a decrease of iodine-complexed amylose and blue intensity. In this study, the starch-iodine method was extended to waxy starches, which stained brown with iodine, and the brown intensity decreased with the increase of the CL%. Moreover, the CL% and RL showed a linear-log relationship.
将普通玉米（NM）、普通马铃薯（NP）、糯玉米（WM）和糯马铃薯（WP）淀粉与七种不同浓度（0.01%、0.05%、0.1%、0.5%、1%、5%、10%）的偏磷酸钠和三聚磷酸钠进行交联。使用低直链淀粉的WM和WP以及A型结晶玉米淀粉和B型结晶马铃薯淀粉，可以确定直链淀粉含量和结晶模式对淀粉交联的影响。结果表明，交联淀粉（CLs）的粘度先升高后降低，最终检测不到粘度；WM在5%时无粘度，NP在1%时无粘度。此外，NM的粘度先升高，在0.5%时变得无法检测。引人注目的是，WP即使在10%的试剂水平（RL）下也能产生粘度，并且在1%时产生了所有样品中最高的粘度。淀粉-碘法是一种用于表征交联度（CL%）的简便高效方法，已应用于普通淀粉，因为CL%的增加导致碘络合直链淀粉和蓝色强度降低。在本研究中，淀粉-碘法扩展到了糯淀粉，糯淀粉与碘反应呈棕色，棕色强度随CL%的增加而降低。此外，CL%和RL呈线性对数关系。
