Effects of chicken feet gelatin extracted at different temperatures and wheat fiber with different particle sizes on the physicochemical properties of gels

Abstract

The objectives of this study were to determine the effects of 1) the extraction temperature (65, 75, 85, and 95°C) of chicken feet gelatin (CFG) and 2) CFG extracted at different temperatures and wheat fiber (WF) with different particle sizes (80, 250, and 500μm) on the physicochemical properties of the resultant gels. Raw chicken feet (CF) were swelled by treatment of an acidic solution [i.e., 0.1N HCl (pH 2)]. The CFG was extracted from the swelled CF at different temperatures. Samples of 4% CFG or a mixture of 3% CFG and 3% WF were prepared using distilled water at 42±1°C and then cooled to form gels. The physicochemical properties of the prepared CFG or the gel with CFG and WF were then investigated. The results indicate that the extraction yield, protein content, and L* values for the CFG samples significantly increased as the extraction temperature increased, whereas the viscosity, melting point, and a* values decreased. For the gel with CFG and WF, the gel strength, melting point, viscosity, and L* and b* values were significantly affected (P <0.05) by the extraction temperature of CFG, but they partially were not affected (P >0.05) by the particle size of WF. The gel with WF and extracted CFG at 65°C had the highest (P <0.05) gel strength, melting point, viscosity, and a* values. In conclusion, CFG or the gel with CFG and WF could be utilized to prepare gelatins or gel with different physicochemical properties by controlling the extraction temperature or particle size of WF, depending on the specific application. Moreover, with its distinct physicochemical properties, the gel with CFG and WF could possibly be used as a non-meat ingredient for fat replacement.