Physicochemical properties and microstructure of surimi treated with egg white modified by tea polyphenols

作者:Zhou, Xuxia; Chen, Ting; Lin, Honghan; Chen, Hong; Liu, Jianhua; Lyu, Fei; Ding, Yuting*
来源:Food Hydrocolloids, 2019, 90: 82-89.
DOI:10.1016/j.foodhyd.2018.07.031

摘要

Effects of egg white (EW) modified by different concentrations (0.2%, 0.4%, 0.6%, 0.8% w/w) of tea polyphenols (TP) on physicochemical properties and microstructure properties of surimi gel were investigated. FTIR analysis showed that TP modification changed the secondary structure of EW proteins, reduced alpha-helix content but increased the content of beta-folding. The TP-modified EW showed significant effects (P < 0.05) in increasing the breaking force and deformation of surimi and resulted in the formation of a stronger network in surimi gel with greater water-holding capacity, as indicated by a lowered expressible moisture content, decreased solubility and increased storage modulus (G') and loss modulus (G '') by dynamic viscoelastic measurement. Protein pattern analysis suggested that the TP-modified EW might contribute to the decrease in the myosin heavy chain (MHC) band intensity of surimi through cross-linking with surimi proteins, which might further increase the superior setting phenomenon of surimi gel. Moreover, a finer and more ordered network of the gel was observed. Therefore, TP-modified EW is efficient in improving the properties of surimi gel, and for the best effect, a concentration of 0.6% is recommended.