Extraction and physicochemical characterization of native and broiler chicken feet gelatin

Poultry processing generates a large amount of industrial waste, which is rich in collagen content. This waste can be utilized for the extraction of valuable components such as gelatin, which can be used as an alternative to mammalian gelatin (porcine and bovine).

Gelatins were analyzed for their yield, proximate analysis, pH, color, viscosity, bloom strength, and texture profile analysis. The yield of broiler chicken feet gelatin (BCFG) was slightly higher (7.93%) as compared to native chicken feet gelatin (NCFG) (7.06%). The protein content was 85.92% and 82.53% for BCFG and NCFG. Both gelatin had moisture content in the standard range (< 15) as given by Gelatin Manufacturers of Europe (GME). Both gelatins showed higher bloom strength (326 g for NCFG and 203 g for BCFG) at 6.67% gelatin concentration, classified as high bloom. Fourier-transform infrared (FTIR) analysis showed amide I, amide A, amide B at 1636 cm^-1, 3302 cm^-1, 2945 cm^-1 for NCFG and 1738 cm^-1, 3292 cm^-1, 2920 cm^-1 for BCFG. At 6.67% gelatin concentration, hardness and cohesiveness values were also higher than commercial gelatin previously studied. The pH values for NCFG were 5.43 and BCFG was 5.31. Both NCFG and BCFG viscosities (4.43 and 3.85 cP) were in the optimum range of commercial gelatins (2-7 cP).

Hence, the present study concluded that both NCFG and BCFG have a huge potential to replace commercial mammalian gelatins (porcine and bovine) in the food industries. However further studies should be done to optimize the extraction process. © 2024 Society of Chemical Industry.