The pH-shifting technology for surimi and its gelation mechanism review and prospect

Surimi is one of the main deep processed products of low value freshwater fish, but because of the small size and numerous small bones, the yield of traditional surimi process (water-washing) is very low. The pH-shifting process can significantly improve the yield of surimi, and obtain higher or equivalent gel strength, is considered a new technology of surimi processing with great potential for industrialization. This paper reviewed the latest literatures related pH-shifting process, including:the effect of pH-shifting process on the protein composition of surimi, molecule structure of protein, gelling properties of surimi, degrading and cross-linking of protein, and microstructure of surimi gel. Furthermore, following viewpoints were suggested:Using proteomic method to investigate the composition of protein of surimi and analyze the function of each protein component during gelation;Gel of pH-shifting surimi was a kind of mixed gel of protein aggregates and undenatured proteins, and the formation of microstructure of the mixed gel could be investigated according to the theory of co-gelling and micro-phase separation.