Combined effect of pH and heating conditions on the physical properties of Alaska pollock surimi gels

Abstract

Physical properties of Alaska pollock surimi paste were investigated as affected by pH (4.0 and 6.0–10.0) and heating conditions (slow and fast). The highest values of gel strength and deformability, as shown by breaking force and penetration distance, were obtained at pH 7.5–8.0, while the lowest values were at pH 10.0 followed by pH 6.0 and pH 6.5, respectively. Two-step slow heating process increased the breaking strength value nearly two times higher than one-step fast heating. The effect of pH was strikingly high at pH 7.5 when gels were prepared using 2-step heating, indicating the pH dependence of endogenous transglutaminase. However, the highest gel strength was obtained at pH 8.0 when gels were prepared in fast heating. Whiteness value (L − 3b*) increased significantly (p