The improvement of gel and physicochemical properties of porcine myosin under low salt concentrations by pulsed ultrasound treatment and its mechanism.

The effects of pulsed ultrasound treatment (250 W, 0-12 min) on gel and physicochemical properties of porcine myosin at low-salt group (0.3 mol/L) and control groups (0.6 and 0.9 mol/L) were investigated. The texture and water holding capacity (WHC) of low-salt group gel were remarkably lower than in medium-salt (0.6 mol/L) and high-salt group (0.9 mol/L). However, 6-min ultrasound treatment could obviously improve the texture and WHC of low-salt group gel. After ultrasound treatment, the protein solubility was increased, as the degree of protein aggregation was reduced. Simultaneously, ultrasound treatment led to unfolding of protein structure and increasing surface hydrophobicity. The three-dimensional network of myosin gel gradually became uniform by 6-min ultrasound treatment. Under 12-min ultrasound treatment, the protein aggregated excessively during the gelation, which led to the deterioration of gel quality. These results suggested that moderate ultrasound treatment is promising to be used to enhance the quality of salt-reduced meat products.