关键词: 莲子淀粉；多酚；流变特性；凝胶网络；微波

Abstract: The aim of this study was to investigate the mechanism underlying the influence of microwave treatment on the rheological properties of a lotus seed starch-chlorogenic acid binary system. The changes in the gelatinization properties, rheological properties and molecular mass of the starch (LS) and the mixed system (CA) were measured after being treated with different microwave powers (200, 250 and 300 W) for 8 min. The results showed that the pasting parameters (except gelatinization temperature), apparent viscosity, hysteresis loop area, elastic modulus and viscous modulus decreased firstly and then increased with the increase in microwave power. Compared with the starch alone, the decreasing trend in the mixed system was more significant, indicating that the cross-linking structure of starch paste was weakened after the addition of chlorogenic acid. According to the results of amylose leaching and molecular mass analysis, chlorogenic acid could effectively interfere with amylose-amylose interaction, weaken the formation of permanent connection zone in the gel network, and make the starch paste system more restorative. As explained above, the formation of starch-chlorogenic acid complex can enhance the thermal stability and shear stability of the starch paste system.

Key words: lotus seed starch; polyphenols; rheological properties; gel network; microwave