The characterization of structural, thermal, pasting and gel properties of the blends of laccase- and tyrosinase-treated potato protein and starch
Jiahao Li, Na Yang, Jun Tang, Yifan Gui, Yu Zhu, Li Guo, Bo Cui
Abstract
Potato protein (PP) was modified with laccase or tyrosinase to obtain covalent cross-linking structures, and then the blends of native/enzyme-treated protein and potato starch (PS) with different ratios were prepared. The FT-IR results suggested the interactions between protein and starch strengthened after enzyme treatment. The relative crystalline raised to 26–29% after the protein mixing with starch. The thermal degradation temperatures of the blends of enzyme-treated protein and PS (296.71–312.91 °C) were apparently lower than that of the blends of PP:PS (312.31–312.76 °C). Compared to the blends of PP:PS, the peak viscosity, trough viscosity and final viscosity of the blends of enzyme-treated protein and PS decreased by 12.7–41.1%. The blends of enzyme-treated protein and PS had a lower storage modulus than native blends. The outcome would provide a view on the theoretical basis of interactions between protein and starch in exploring favorable potato staple foods.