Abstract:

The objective of this study was to evaluate the effect of ionic strength on the emulsifying and physico-chemical
properties of pork myofibrillar proteins (MP). MP was extracted and its emulsifying and physico-chemical properties
including emulsifying capacity (EC), emulsion stability (ES), solubility and intermolecular hydrogen bonds, surface
hydrophobicity, and active and total sulfydryl groups under different ionic strengths were measured correlated with each
other. The results showed that EC, ES and solubility increased with increasing ionic strength. Meanwhile, the contents
of active sulfhydryl group and intermolecular hydrogen bonds tended to increase, whereas the surface hydrophobicity
decreased. Total sulfhydryl groups did not exhibit any change. The solubility was positively correlated with either EC
(P < 0.05) or ES (P < 0.01), and active sulfydryl groups were positively correlated with EC (P < 0.01). On the other hand,
the surface hydrophobicity was negatively correlated with either EC (P < 0.01) or ES (P < 0.05). Therefore, ionic strength
can affect the emulsifying and physico-chemical properties of MP, with a significant or extremely significant correlation
observed between these two properties.

Key words: myofibrillar protein, emulsification, ionic strength, solubility