The influence of chitosan on physico-chemical properties of chicken salt-soluble protein gel

The feasibility of chitosan as cold-set binder in a model with chicken salt-soluble proteins (SSP) was investigated. The parameters studied were molecular weight (MW), percent degree of deacetylation (%DD), and concentration of chitosan, each at three levels (low, medium, and high). The cold-set gels were formed by mixing various preparations of chitosan with 8% w/v SSP and setting at 4'C for 24h. The physico-chemical properties of the developed gels, i.e. color, theological characteristics, texture, disultide content, nondenaturing gel-electrophoresis pattern, and gel structure, were determined. Chitosan can act as cold-set binder when using in the form of alkali-precipitate. The MW, %DD and concentration significantly affected all of the characteristics of cold-set SSP gel. The inclusion of chitosan resulted in improvement of texture (p < 0.05), increasing of the disulfide content (p < 0.05), and improvement of the rheological characteristics and structure of cold-set SSP gel, while the pattern on non-denaturing gel-electrophoresis remained unchanged. However, the inclusion of chitosan also increased the lightness and paleness (p < 0.05). The appropriate characteristics of chitosan giving the best cold-set gel was chitosan with MW of 1.84 x 10(5) Da, 94%DD at the concentration of 1.5% by weight. (C) 2007 Elsevier Ltd. All rights reserved.