Optimal conditions for obtaining collagen from chicken feet and its characterization

Abstract The objective of this study was to extract collagen from chicken feet, determining optimal extraction conditions according to acetic acid concentration, pepsin content and time of enzymatic hydrolysis. A factorial design 23 was used, with three replications at the central point, totaling 11 experiments. The response variable studied was the collagen content of the isolate obtained. In addition to the optimization, the characterization of the isolates with higher and lower collagen content, in relation to the amino acid profile, electrophoretic profile, peptide hydrophobicity and functional properties, such as water solubility, water retention capacity and emulsifying activity, were carried out. The proposed model was statistically significant, with conditions of higher collagen content of 0.3 mol/L of acetic acid, 0.2% of pepsin and 12 hours of hydrolysis. The collagen isolate under these conditions showed higher iminoacids content, higher sum of peptide areas, higher solubility in water and water retention at 60 °C. The treatment with lower collagen content showed high emulsifying activity. The collagen isolate of the chicken feet presented characteristics makes it suitable for application in the food industry.