STUDIES ON THE FUNCTIONALITIES OF MICROBI AL TRANSGLUTAMINASE FOR FOOD-PROCESSING .2. EFFECTS OF MICROBIAL TRANSGLUTAMINASE ON THE TEXTURE OF GEL PREPARED FROM SUKETOUDARA-SURIMI

Effects of microbial transglutaminase (MTGase) on the texture of gel p repared from suketoudara surimi were investigated. The jelly strength and strain of the gel increased with an increase of MTGase. The textur e improvement of surimi gel by MTGase was related to salt concentratio n,: namely the jelly strength increased with an increase in salt conce ntration The texture improvement by MTGase was observed even in low co ncentration of surimi diluted with water. The increase in jelly streng th and strain of the gel was depressed by an addition of sucrose, and enhanced by an addition of potato starch. In the cases of the setting at below 30 degrees C and at low concentrations of MTGase, the jelly s trength increased in accordance with the prolongation of setting time. On the other hand, in the case of the setting at 40 degrees C and 50 degrees C, the jelly strength increased with setting time, and then re ached constant. The content of epsilon-(gamma-Glu) Lys linkage increas ed with an increase of MTGase, Especially, in the cases of suketoudara SA, its content increased rapidly by the setting at low temperature. Based on the results of SDS-PAGE, the band of myosin heavy chain (MHC) of SA surimi paled in the presence of MTGase above 1.5 similar to 3 u /g protein, and that of C surimi faded at MTGase concentrations above 3 similar to 5 u/g protein.