Desorption isotherms of salted minced pork using K-lactate as a substitute for NaCl

The aim of this study was to obtain and compare water desorption isotherms of ground meat containing NaCl (0.107 kg NaCl/kg raw-meat dry matter) and/or K-lactate as NaCl substitute at two different levels of molar substitution (30% and 100%). A thin layer of salted ground meat was dried and sampled at pre-determined times. The moisture content of the samples and their water activities (aw) were measured at 5 °C and 25 °C. Results showed that ground meat with NaCl and/or different K-lactate contents had a similar water desorption isotherm for aw ranging from 0.7 to 1.0. Below 0.7, the water equilibrium content fell with small decreases in aw faster for meat with NaCl than for meat with K-lactate. K-lactate could reduce the excessive hardening at the surface of salted meat products. Experimental desorption isotherms were compared to those estimated using two approaches of the Ross equation. Models provided a good fit for the experimental data.