Physical, chemical and functional properties of gelatin extracted from the skin of rohu, Labeo rohita and yellowfin tuna, Thunnus albacares

Abstract

Gelatin, a commercially important polypeptide derived from collagen has wide applications in food and pharmaceutical industry. Gelatin extracted from the tropical fish species has an advantage over cold water species, the former having better rheological properties. In this study the physic-chemical properties of gelatin extracted from the skin of rohu, Labeo rohita and yellowfin tuna Thunnus. albacare were studied. The results indicated that tuna skin gelatin was superior in terms of yield, gel strength, viscosity and foam stability. However, rohu skin gelatin had a better colour and foam formation ability. The amino acid composition showed significantly higher content of glycine (27.5%) and imino acid (26.98%) in tuna skin gelatin. Although tuna gelatin had better gel strength, rohu skin gelatin was found to be more suitable for food applications as it had better colour and sensory properties.