Abstract: Duck thigh meat was salted with sodium chloride (≥ 99.1%) alone or in combination with potassium chloride (30% KCl + 70% NaCl, namely sodium replacement). Changes in the mass, water content and salt content of duck thigh meat were analyzed during its salting with vacuum tumbling. The kinetic data of mass transfer were obtained. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was carried out to study the influence of tumbling salting with different salts on the protein profile of duck thigh meat. The results showed that changes in meat mass (ΔMt0), water content (ΔMtw) and salt content (ΔMts) had a good correlation with the square root of curing time (t0.5) for the two groups. ΔMt0, ΔMtw and ΔMts increased rapidly with curing time up to 4 h. The effective diffusion coefficient De of full-sodium and reduced-sodium cured meat was 4.432 × 10-8 and 4.462 × 10-8 m2/s, respectively. There was a slight difference between them. The gel electrophoresis maps showed that myofibrillar proteins were constantly degraded during the salting process irrespective of whether sodium chloride was replaced by potassium chloride. In conclusion, the rate of mass transfer can remain unchanged regardless of the replacement of sodium chloride by potassium chloride.

Key words: duck meat, salt reduction, salting with vacuum tumbling, mass transfer kinetics, gel electrophoresis