Effects of nanofiber cellulose on functional properties of heat-induced chicken salt-soluble meat protein gel enhanced with microbial transglutaminase

The effects of carboxylated nanofiber cellulose (cNFC) on chicken breast muscle salt-soluble protein (SSP) in model systems in the presence or absence of transglutaminase (TG) were investigated. cNFC at concentrations of 0%, 2.5%, 5%, 7.5%, and 10% was introduced into salt-soluble protein. The results indicated that cNFC contributed to the improvement of water-holding capacity of gels, but this effect was insignificant when TG was added into the composite gel. This was attributed to steric hindrances of the pre-formed TG cross-linked network. The presence of cNFC enhanced gel strength in the model system with TG. Based on scanning electron micrographs (SEM) and confocal laser scanning micrographs (CLSM), the addition of cNFC to SSP produced a hydrogel in the form of a semi-IPN (Interpenetrating Polymer Network). In the presence of TG, this structure was more compact. No strong intermolecular interaction between SSP and nanocellulose was evident from FTIR spectra, suggesting the occurrence of physical entanglement of cNFC in the composite gel. In summary, the presence of cNFC can improve gel properties of salt-soluble protein, depending on its concentration and the gel structure, thereby providing potential applications in restructured meat products.