Valorization of discarded industrial processing wastes of Siboga squid (Doryteuthiis sibogae) for the extraction and physico-chemical characterization of gelatin

A growing concern on the accumulation and disposal of fish processing discards and environmental degradation induces a profound attraction on the development of valuable byproducts for human purposes. Gelatin was isolated from Siboga squid ( Doryteuthiis sibogae ) skin through cold maturation process and its physico-chemical as well as structural properties viz . Water Holding Capacity (WHC), emulsifying capacity, emulsifying stability and viscosity were analyzed. The alkaline treatment of skin yielded 7.5 % gelatin powder. Extracted gelatin was characterized using UV-visible spectroscopy, 1 H NMR, FT-IR and Raman analyses. Based on FT-IR and Raman fingerprints, peak located at 1664 cm -1 (C=O stretch Amide I band) could be inferred that secondary structure of proteins as well as coiled structure of gelatin. Topographic analysis by AFM showed presence of aggregates of the polymer. The results suggest that the Siboga squid gelatin is an alternative source of gelatin and its potential applicability at industrial scale.