Effects of chitosan on the gel properties of salt-soluble meat proteins from silver carp

Chitosans (CHI) with different degree of deacetylation (DD) (60.5%, 65.4%, 70.8%, 77.3%, 86.1%) and different molecular weight (MW) (299, 410, 600, 706, 880 kDa) were obtained. Heat-induced composite gels were prepared from 4% salt-soluble meat proteins (SSMP) with chitosans at 0.6 mol/L NaCl, pH 7.0. Penetration forces and storage modulus of SSMP-CHI composite gels increased proportionally with increasing amount of molecular weight. Gel containing chitosan with DD 77.3% exhibited the highest penetration force and storage modulus. The SEM observations showed that SSMP-CHI incorporated gels were compact and fine compared with that of SSMP. Chemical forces involved in SSMP-CHI composite gels were investigated by determining the effects of NaCl, urea, propylene glycol, and 2-MeSH on penetration forces. Results of these studies demonstrated that interaction between CHI and SSMP contributed to the enhancement of texture of the SSMP-CHI composite gels by electrostatic interactions and hydrogen bonds. (C) 2010 Elsevier Ltd. All rights reserved.