Physicochemical properties, in vitro digestibility, and 3D printing performance of buckwheat starch complexes co-gelatinized with large-leaf yellow tea soluble dietary fiber

This study investigates the effects of soluble dietary fiber from large-leaf yellow tea (TSDF) on the physicochemical properties, in vitro digestibility, and 3D printing performance of buckwheat starch (BS). The results show that TSDF effectively inhibits short-term retrogradation of BS, reduces its crystallinity and short-range order, and does not form <i>V</i>-type complexes with BS. As the TSDF content increases, peak viscosity decreases, gelation temperature increases, and gelation enthalpy decreases from 13.93 J/g to 12.31 J/g. Additionally, TSDF reduces the digestibility of BS and promotes an increase in pore size and thickening of pore walls in the colloidal structure. A moderate amount of TSDF (0.3 %) improves the 3D printing accuracy of BS. This study provides new insights for dietary fiber-modified starch and its application in low glycemic index and 3D printed foods.