Vol. 9, Issue 4 (2020)

Author(s):
Sweta Singh, Kunal Singh and Baljor Singh

Abstract:
Carps are a major source of protein for millions of people in Asia. The wastes generated from such fishes during their processing are huge and can be effectively utilized for the preparation of gelatine, a protein. In present study, gelatin was prepared from catla skin and scales and different drying techniques like tray drying, freeze drying and drum drying were used during the drying processes. These gelatins were assessed for their physical, chemical, rheological properties and functional properties and compared with those of the commercially available gelatins. Tray drying of gelatin resulted in the highest yield 11.7%. Hydroxyproline content was highest for commercial gelatin 7.5%. while the commercial gelatins had greater L* (brightness) value (85).the tray and drum dried gelatins had greater and similar b* yellowness values (30-33). The odor profile by sensory evaluation of gelatins revealed least fishy odor for commercial and drum dried gelatins. FTIR (Fourier trans for infrared spectroscopy) analysis confirmed the conformational structure of gelatin while DSC (differential scanning calorimetry) results revealed the characteristics glass transition temperatures of the gelatins. SDS-PAGE pattern of the gelatin revealed major bands corresponding to chain and cross- linked component, chain. The gel strength of gelatine was measured and gelling ability were found more in drum dried gelatine (1256 gf). The emulsifying stability of the tray dried was the highest (73%) closely followed by drum dried gelatin. Drum dried gelatin had the least foaming capacity. While freeze dried gelatin had the highest water holding capacity (7.5 ml/g) drum dried gelatin had the highest fat binding capacity (17.5 ml/g). The drum dried gelatin showed the maximum solubility (92-93%) at Ph 3,7 and 11 indicating that the drum dried gelatins can be used in a wide range of food applications from acidic to alkaline without affecting the solubility.