The results were similar to the report by Lee and Park (1998), which indicated that shear stress of Alaska pollock gel increased by 34% after the addition of 0.2% calcium carbonate. Benjakul et al. (2004) also reported that breaking force and penetration distance of bigeye snapper surimi gel increased significantly with the addition of calcium carbonate ranging from 0.5 to 1.5%. According to Hemung and Yongsawatdigul (2005) and Yongsawatdigul and Sinsuwan (2007), Ca2+ ion, in addition to being a TGase activator, induced the unfolding of myosin at 10–100 mM as evidenced by the increase of surface hydrophobicity and loss of a-helical structure. As a result, more exposure of those reactive residues was reported to favour a TGase mediated reaction, which improves gel texture.