Effect of cross-linking with sodium trimetaphosphate on structural and physicochemical properties of tigernut starch

Abstract

With sodium trimetaphosphate as cross-linking agent, the cross-linked tigernut starch (CLTS) was prepared in this study. The effects of cross-linking on the structure and physicochemical properties of tigernut starch were also investigated. FT-IR analysis confirmed the formation of CLTS. X-Ray diffraction (XRD) results suggested that cross-linking not only retained the crystallization type of starch (C-type), but also enhanced the crystallinity. Compared with the native tigernut starch (NTS), CLTS had lower solubility and swelling power, the better syneresis and freeze-thaw stability. It was more prone to settlement. The pasting temperature and peak viscosity of CLTS were superior to those of NTS. It was easier to regenerate at low temperature, and its thermal stability was also significantly improved. Our results provide a reference for the in-depth development of tigernut starch.