Combination effects of microbial transglutaminase, reducing agent, and protease inhibitor on the quality of hairtail surimi

A combination of microbial transglutaminase (MTGase), reducing agent and pr otease inhibitor was employed to improve the quality of underutilized fish surimi. SDS-PAGE indicated that cross-linking of myosin heavy chain (MHC) o ccurred in MTGase-contained samples, while MHC of samples without MTGase di sappeared after 120 min incubation at 45 degrees C. Although the gel-formin g ability increased with MTGase added up to 0.6 unit/g, it was still too lo w to be commercially acceptable. However, the combined use of 0.1% NaHSO3, 0.01 mM transepoxysuccinyl-L-leucylamido-(4-guanidino)butane (E-64) and 0.3 5 units MTGase/g substantially improved the quality of hairtail surimi. Bas ed on this result, the combined use of E-64, MTGase and NaHSO3 seemed to be a better way to improve gel-forming ability of hairtail surimi.