Effect of oxidized phenolic-containing plant extracts on gel properties of goatfish surimi

Abstract

The effect was studied of oxidized phenolic-containing plant extracts from Vietnamese coriander and holy basil at 0.1–0.4% protein content on the gel properties of goatfish (Mulloidichthys martinicus) surimi. The lowest expressible moisture content and the highest breaking force, deformation,gel strength and texture profile (hardness, gumminess, chewiness) were observed in surimi gel with 0.1% oxidized phenolic-containing plant extracts from Vietnamese coriander. The trichloroacetic acid-soluble peptide content decreased as the concentration of extract increased. Analysis of protein subunits using sodium dodecyl sulfate-polyacrylamide gel electrophoresis demonstrated that as the concentration of extract increased the intensity of the myosin heavy chain band decreased, whereas that of the polymerized protein band increased. Compared to the control, the microstructure of surimi gel with 0.1% oxidized phenolic-containing plant extracts from Vietnamese coriander was denser, more ordered and had a more uniform protein network. Compared to the control, sensory evaluation resulted in higher liking scores for surimi gel with 0.1% oxidized phenolic-containing plant extracts from Vietnamese coriander with regard to springiness, texture and overall liking. Therefore, the addition of 0.1% oxidized phenolic-containing plant extracts from Vietnamese coriander could improve the gel-forming ability of goatfish surimi without having any adverse effects on the sensory properties.