Effects of microbial transglutaminase and sodium alginate on cold-set gelation of porcine myofibrillar protein with various salt levels

The effects of microbial transglutaminase (TG) and sodium alginate (SA) systems on cold-set gelation of myofibrillar protein (MP) at various salt levels were investigated. The gelation kinetics data showed that both TG and SA had optimal but different salt levels to form an acceptable cold-set MP gel. Although their gelling characteristics were altered with different salt levels, the combination of TG and SA showed a rapid cold-set MP gel formation, regardless of salt levels. The effect of TG and SA on gel strength was reversed by increasing the salt level, while the cold-set MP gel strength of the TG and SA combination was not affected by salt levels. Furthermore, the SA system contributed to improved water-binding ability and cold-set MP gel formation, while the TG system enhanced the gel strength of the MP after cooking at low-salt levels. In addition, TG's effects on gel strength of MP increased at higher salt levels, the SA system prevented the moisture loss induced by the TG reaction. There was no evidence of any interaction between SA and MP in the thermogram and gel electrophoresis data. Results from this study suggested that a system combining TG with SA had the potential advantage of improving the water-binding ability and producing cold-set MP gelation at an even lower salt level than TG alone.