Effect of Setting Condition on the Gel Properties of Surimi from Catfish (Clarias gariepinus)

Abstract

Background and Objective: Differences in gelling properties may be attributed to the chemical composition and setting conditions at a particular temperature employed during the formation of surimi gels. The aim of this study was to investigate the chemical composition and effect of setting condition on the gel properties of surimi prepared from Clarias gariepinus (local name “lele dumbo”). Materials and Methods: Kamaboko gel was prepared by incubating the surimi sol at 35EC prior to heating at 90EC, while directly heated gel was prepared by heating the sol at 90EC. Data were subjected to analysis with a one-way ANOVA for comparison of means at a 5% level of significance. Results: The myofibrillar and sarcoplasmic protein contents were 16.27±0.23 and 2.02±0.06 mg N gG1 surimi, respectively. About 40% of transglutaminase activity was retained in the final surimi. Kamaboko gel showed higher gel strength, hardness and springiness when compared with directly heated gel. However, it had a lower expressible moisture content. Both surimi gels showed no significant difference in the whiteness parameter. Electrophoretic patterns indicated that although myosin heavy chain may undergo polymerisation in both, kamaboko gel and directly heated gel, the extent of polymerisation may be greater in kamaboko gel. Conclusion: The two-step heating involving setting of surimi sol at 35EC prior to heating at 90EC could enhance gel properties of lele dumbo surimi.