Preparation and functional characterisation of fish skin gelatin and comparison with commercial gelatin

Gelatin was extracted from the skin of farmed giant catfish (GC) and tilapia (TP) at a yield of 19.50% and 23.34% (wet wt). It was high in protein (8488%) but low in fat (0.091.24%) and ash content (0.150.17%). The GC exhibited lower emulsifying activity (2435%), but greater foam ability (98110%), water holding capacity (477844%) and fat binding capacity (25413314%) than commercial beef skin gelatin (BF) (P<0.05). GC and TP showed comparable functional properties to BF. SDS-PAGE patterns of TP gelatin showed high band intensity for the - and -components, while the lowest band intensity of the major component was found in the BF. From the study, it can be concluded that the farmed freshwater fish skin GC and TP is a prospective source for producing a significant gelatin yield with desirable functionalities. Because of these, fish skin gelatin could be more effectively and widely used in food industries as a good food ingredient.