Effects of emulsified lard and TGase on gel properties of threadfin bream (Nemipterus virgatus) surimi

The effects of emulsified lard and transglutaminase (TGase) on the characteristics of threadfin bream surimi gels were investigated. Results showed that irrespective of TGase addition, the storage and loss modulus of surimi paste decreased with the increasing emulsified lard content during gel formation. The breaking force and deformation of surimi gels decreased from 857.33 g to 16.91 mm to 234.14 g and 8.44 mm respectively, after the addition of emulsified lard (2.5 g/100 g surimi). With further increase in the concentration of emulsified lard, the breaking force decreased, and the deformation remained almost unchanged. However, the weakening effect of emulsified lard was restrained by TGase. Regardless of TGase addition, the lightness, yellowness, and juiciness of surimi gels increased with the emulsified lard concentrations. The disulfide cross-linking among myosin heavy chains (MHCs) in surimi gels was inhibited by the emulsified lard, and the covalent cross-linking among MHCs was promoted by TGase. Emulsified lard and TGase could promote the hydrogen bonds among protein molecules in surimi gels. The compact and dense 3D gel network was destroyed by the added emulsified lard but protected in the presence of TGase. Therefore, high-quality surimi products could be produced under the combined action of emulsified lard and TGase.