The structural, thermal, pasting and gel properties of the mixtures of enzyme-treated potato protein and potato starch

Abstract

To understand the interactions between enzyme-modified potato proteins and potato starch, herein transglutaminase or peroxidase was used to create covalent crosslinked structure of potato protein. The mixtures of native or enzyme-treated protein and potato starch in different proportions were prepared and the structural and physicochemical characteristics were studied. The results revealed that the new covalent and/or noncovalent linkages formed after enzyme modification of potato protein. Compared with the mixtures of native protein and starch, the mixtures of enzyme-treated protein and starch had larger shear resistance (breakdown value decreased by about 2–100 times) and higher gel strength (G′ and G″), but smaller thermal stability (312.3–307.3, 309.1 °C) and lower peak viscosity (decreased by 1.5–4 times). In conclusion, transglutaminase or peroxidase accelerated the formation of cross-networked structure in potato protein, which increased the interaction with starch, hence greatly improving the gel properties of the mixture of protein and starch.