Physicochemical and textural properties of tartary buckwheat starch after heat–moisture treatment at different moisture levels

Tartary buckwheat, which has nutritional and health benefits, has been consumed in China for so many years. However, its predominant component, starch, limits the application range of tartary buckwheat in the food industry. In this study, tartary buckwheat starch (TBS) was extracted and subjected to heat–moisture treatment (HMT) at different moisture levels (20–35%). Both the solubility and swelling power of native starch significantly decreased following HMT. In HMT-modified TBS, oil absorption capacity decreased and water absorption capacity increased with increasing moisture level. The typical A-type X-ray diffraction pattern of native starch was not affected by HMT. Gelatinization temperature, gelatinization temperature range, and relative crystallinity increased with increasing moisture level. However, peak viscosity, gelatinization enthalpy, hardness, and adhesiveness of starch gels significantly decreased with moisture level. These results revealed that the structure and physicochemical properties of TBS can be modified by HMT to improve its thermal stability and extend its application range.