Physicochemical Properties of Gelatin from Jellyfish Rhopilema hispidum

The objective of this study was to elucidate the physicochemical characteristics of gelatin extracted from jellyfish Rhopilema hispidum. We investigated the proximate composition, amino acids, gel strength, gelling/melting points, dynamic viscoelastic properties, and viscosity of jellyfish gelatin. Jellyfish gelatin contained 12.2 % moisture, 1.5 % lipid, 2.1 % ash, and 84.8 % protein. Glycine, hydroxyproline, proline, and alanine were the predominant amino acids. The gelatin showed a gel strength of 31.2 kPa, a gelling point of 18.0°C, and melting point of 22.3°C. The gelatin was composed of α1-chain, α2-chain, β-chain, and γ-chain. During cooling and heating process, jellyfish gelatin showed lower elastic modulus (G') and loss modulus (G'') values than mammalian gelatin. Jellyfish gelatin did not show superior rheological properties to mammalian gelatin, like other fish gelatin; however, it can be used in various food and cosmetic products not requiring high gel strength