Porcine plasma proteins as gel enhancer in bigeye snapper (Priacanthus tayenus) surimi

Cohn's fraction I-S from porcine plasma showed the highest transglutaminase activity, compared to fi-actions I, II+III, IV, IV-I. The optimum temperat ure for incorporating monodancylcadaverine into dimethylated casein was 45C Plasma transglutaminase in fi-action I-S was activated by calcium chloride but was inhibited by A-ethylmaleimide, ethylenediaminetetraacetic acid and ammonium chloride. The addition of fraction I-S into bigeye snapper surimi resulted in a substantial increase in gel breaking force and deformation, particularly in the presence of calcium chloride and thrombin. No changes i n whiteness and water holding capacity, were observed in surimi gel with th e addition of 0-0.5% of fraction I-S. Fraction I-S was found to catalyze no ndisulfide covalent cross-linking of myosin heavy chain. The combination of endogenous and plasma transglutaminase enhanced surimi gelation.