Gelling behavior of bio-tofu coagulated by microbial transglutaminase combined with lactic acid bacteria.

The aim of this study was to investigate the gelling behavior of proteins in bio-tofu (soymilk-cow milk mixture gel) coagulated by microbial transglutaminase (MTGase) combined with lactic acid bacteria (LAB). It was shown that MTGase (3.0 U/g protein) treatment of soymilk-cow milk mixture (SCMM) could not induce gelation at 43℃ even if the incubation was lasting 4 h. However, the concomitant use of LAB (0.025 UC/L) along with MTGase could induce the formation of denser and finer gel network with smaller pores and higher storage modulus (G') compared to SCMM treated with only LAB. Electrophoresis and mass spectrometry results indicated that LAB improve MTGase-dependent polymerization of proteins. In addition, this study investigates the effect of LAB and MTGase treatment on the rheology behavior of the derived gel products. In general, the use of both bio-coagulants for the manufacture of a mixed protein gel, might open new horizons in the field of novel nutrional and functional foods.