Analysis of salt penetration enhancement in meat tissue by mechanical treatment using a tumbling simulator

Brining-tumbling is a key step in cured and/or cooked meat product manufacture. The massaging of meat enhances NaCl homogenization which, in combination with mechanical action, enhances protein solubilization. To clarify the underlying mechanisms and quantify their effects, meat tissue from Semimembranosus pork muscles was tested under various brining conditions: static brining (a), static brining after massaging (b), and brining-massaging (c). Using trials performed on a lab-scale tumbling simulator, massaging was controlled and characterized by three mechanical indexes. Apparent NaCl diffusivities (Dsalt) were estimated from measured NaCl profiles using Fick's diffusion theory. It was demonstrated that tissue damage is not the main factor explaining salt migration enhancement: a-vs-b comparison showed a 20% increase in Dsalt, which was explained by observed microstructural changes. a-vs-c comparison showed a 200% increase in Dsalt, possibly due to water movement promoted by meat deformation. Calculations were used to compare spatial distributions of NaCl within small meat cubes during static brining versus brining-tumbling.