A comparative study of the effects of three typical phenolic compound on surimi gel and its mechanism
Jinling Li, Ying Mao, Wangyang Shen, Weiping Jin, Shanbai Xiong, Yang Hu
Abstract
The effects of different phenolic compounds (Epigallocatechin gallate, EGCG; Catechin, CC; Tannic acid, TA) at different phenol hydroxyl concentrations on the gel strength, water holding capacity (WHC), water distribution, and micro-morphology of surimi gels were investigated. Breaking force and deformation of surimi gels treated with EGCG, CC, and TA were increased by 20%, 15%, 12% and 14%, 7%, 4%, compared with untreated surimi gel. Polyphenols increased the WHC of surimi gels and induced the conversion of α-helix to β-sheet in proteins, which was beneficial to the gelation of surimi gel. Surimi gels treated with polyphenols had a complete three-dimensional network structure and relatively uniform and small pores, especially EGCG cross-linked surimi gel. Molecular docking indicated that the interactions between EGCG, CC, TA and myosin heavy chain II A were mainly hydrogen bond and hydrophobic interaction, and their binding energies were −37, −31, and −26 kJ/mol. The binding energy of polyphenols with myosin heavy chain II A correlates with their cross-linking ability with proteins, and the lower the binding energy is, the stronger the cross-linking ability is. This study provides important information to elucidate the mechanism of phenolic compounds regulating the physical properties of surimi gel. • Epigallocatechin gallate, catechin and tannic acid enhanced the texture of surimi gel. • EGCG, catechin, and tannic acid promoted α-helix to β-sheet conversion in proteins. • EGCG, catechin, tannic acid bond to myosin with energies of −37, −31, −26 kJ/mol.