Preparation of collagen concentrate from chicken feet

The meat-processing industry produces a huge and ever greater amount of involuntary by-products at slaughterhouses, which increase significantly the waste amount. In terms of poultry, these comprise feet, heads, viscera and skin - items that are rich in protein, especially collagen. The latter can be gained through a procedure that involves grinding and defatting raw material, since poultry by-products from meat-processing industry contain a wide range of fat (15 – 70 %). Indeed, it is also necessary to extract other non-collagenic matter, such as pigment and water-soluble proteins. In this study, non-collagen components were removed by treatment of chicken feet in 0.1% NaOH. Three methods of defatting of raw material (applying NaHCO3, lipolytic enzyme and 10 different solvent systems) were tested. The use of solvent mixture of petroleum ether and ethanol proved to be the most efficient method of defatting chicken feet with a residual fat content of approximately 5 %. Collagen concentrate prepared this way possesses the potential to be utilized by commercial sectors, such as the food or pharmaceutical industry. © 2018 Computer Society of the Republic of China. All rights reserved