Physicochemical characteristics of muscle proteins from barracuda (Sphyraena jello) of different weight groups

The physicochemical properties of muscle proteins extracted from two different weight groups (500 and 1500 g) of barracuda (Sphyraena jello) are discussed. Solubility of sarcoplasmic protein (SPP) from groups I and II fishes were 107 and 167.18 mg/g, respectively. The myofibrillar protein (MFP) concentration was significantly higher in group II. The concentration of reactive sulphydryl group and Ca2+ ATPase activity of MFP were higher in group II fishes than in group I fishes. Surface hydrophobicity of MFP was noticeably higher for group I fishes compared to the other group. High emulsion activity index (EAI) was noticed for group I fishes. EAI of SPP increased but that of MFP decreased with increase in protein concentration in both the fishes. MFP from group I fishes showed better emulsion stability (ES) and the ES showed concentration-dependent increase in both groups for both SPP and MFP. Foam expansion was higher in group I fishes, but foam volume stability (FVS) of both the groups did not show any significant difference. Viscosity, water holding capacity (WHC) and gel strength (GS) were higher for group I fishes. Electrophoretogram of SPP and MFP of both the groups show difference in band pattern indicating that proteins expressed during various stages of growth vary. (C) 2006 Swiss Society of Food Science and Technology. Published by Elsevier Ltd. All rights reserved.