Characteristics of gelatin from giant grouper (Epinephelus Lanceolatus) skin

Abstract

Gelatin extraction from the skin of giant grouper (Epinephelus lanceolatus) was conducted by acid process with a yield of 20.27 g/100 g wet skin sample. The characteristics of extracted gelatin from giant grouper was investigated in this study, and further compared to that from commercial tilapia. Results showed that when compared to commercial tilapia, giant grouper had lower levels of bloom strength and foam formation ability, but greater values of viscosity, foam stability, and lightness (L∗) on gelatin skin. Sodium dodecyl sulphate-polyacrylamide gel electrophoresis analysis revealed three high-bands intensities of major protein components of giant grouper skin gelatin, representing α1-chain, α2-chain, and β-components, and was similar to that of standard calf skin collagen type I. Compared to giant grouper, commercial tilapia contained extra proteins with molecular weight less than 70 kDa on the sodium dodecyl sulphate-polyacrylamide gel electrophoresis of both skin gelatins.