Characteristics and Physicochemical Properties of Gelatin Extracted from Scales of Seabass (Lates calcarifer) and Grey Mullet (Mugil cephalus) in Vietnam

In this study, gelatin was obtained from the scales of seabass (Lates calcarifer) and grey mullet (Mugil cephalus) collected in Vietnam by using Alcalase (R) 2.4L FG for pretreatment and electrochemically activated water with pH 2.0-2.5 for extraction. The characteristics and physicochemical properties of gelatin were investigated. The results indicated that the gelatin had a high protein content (88.6-90.0%) with ash (1.43-1.55%) and no fat. The gelatin was identified as type A due to its pH value. The yields of gelatin were 14.1-15.2%. The gel strength and melting point were 270.3g and 26.7 degrees C, respectively, for gelatin from seabass scales and 249.1g and 25.9 degrees C, respectively, for samples from grey mullet scales. In contrast, the viscosities of gelatin were found to be 6.97 cP for seabass and 8.73 cP for grey mullet. Both gelatins contained -chain and -chain as the major components. Circular dichroism spectra indicated that the triple helical structure in collagen was almost transformed to the random coil structure in gelatin. The proportion of imino acids was high (197-205 residues/1,000 residues). So, gelatin from seabass and grey mullet scales could be used as a potential replacement for mammalian gelatin.