Effects of proteolysis pretreatment on the formation, structural changes and emulsifying properties of rice glutelin amyloid-like fibrils

Enzymatic hydrolysis prior to fibrillation can improve the formation capacity of food protein fibrils, which further affects their functional properties. In this study, the effects of proteolysis pretreatment with trypsin on the formation, structural changes and emulsifying properties of rice glutelin (RG) fibrils were investigated. The results showed that the formation of protein fibrils was confirmed by Thioflavin T fluorescence spectra, and the fibril formation capacity was enhanced by trypsin proteolysis pretreatment. The fibrils derived from the enzymatically modified rice glutelin (E-RG) had more β-sheet structures (58.20 %). Hydrogen bonds and hydrophobic interactions were mainly involved in the formation of fibrils. More and more flexible fibrils were observed during the E-RG fibrillation. In addition, the emulsifying activity (21.68 m²/g), stability (26.84 min) and apparent viscosity of the E-RG fibrils were improved. Hence, these findings can provide a reference for broadening the application of rice glutelin fibrils in food processing.