PREPARATION AND CHARACTERIZATION OF GELATIN EXTRACTED FROM THE SKINS OF ROHU (LABEO ROHITA) AND COMMON CARP (CYPRINUS CARPIO)

Abstract

ABSTRACT Gelatin was extracted from the skins of rohu and Common carp, and its physicochemical properties were studied. The yield of gelatin obtained from the skin of rohu and Common carp were 12.93 and 12%, respectively. The corresponding viscosity values were 6.06cP and 5.96cP. Rohu and Common carp skin gelatin had high content of imino acids i.e., 20.49 and 19.16%, respectively. Rohu gelatin had a significantly higher (P < 0.05) melting point than that of Common carp skin gelatin. The setting temperature observed for the gels from rohu and Common carp was 18.52 and 17.96C, respectively. Rohu and Common carp skin gelatins were found to have a mild but easily perceivable odor. The gelatins from the skin of rohu and common carp had a snowy white appearance and were light-textured. Rohu skin gelatin had significantly higher gel strength compared with Common carp skin gelatin. Foam formation ability and form stability of Common carp gelatin was significantly lower (P < 0.05) than that of Rohu gelatin. Rohu skin gelatin had the high fat-binding capacity. In this study, the functional properties observed for gelatins from the skin of rohu and Common carp are similar, if not better than many of the gelatins from other fish sources, and can be used as potential substitutes for the same in many applications. PRACTICAL APPLICATIONS Among the cultured carps, rohu (Labeo rohita) and Common carp (Cyprinus carpio) contribute significantly to the Aquaculture production in India. These species are presently being increasingly used for the preparation of mince and fillet-based value added products, with skin forming a major portion of the fishery waste thus generated. Hence, based on the availability and commercial importance and with the objective of efficient utilization of fish skin waste, these species were chosen for studies on gelatin extraction. It was observed that the physicochemical and functional properties for rohu and Common carp skin gelatins are similar, if not better than many of the gelatins from other fish sources and can be used as potential substitutes for the same in many applications. There is a future scope for developing binary blends of these gelatins with animal gelatins that are completely compatible and commercially useful in many applications.