Mathematical modeling of NaCl and KCl diffusion in mozzarella cheese using static and stirred brine

Abstract

Sodium chloride salt is used in the cheese salting because it promotes sensorial changes besides preserving the food, but in excess can cause hypertension. Therefore, it has been partially replaced by potassium chloride to not affect the sensory characteristics. In this work the mozzarella cheese was subjected to the diffusion of Na+ and K+ in brine by static and stirred immersion. The diffusion was modeled using the second law of Fick and simulated by the finite element method through the software COMSOL Multiphysics® version 5.2. The main, cross coefficients and the relation between mass transfer coefficient and the mass conductivity were determined through simplex optimization, minimizing the percentage errors between the experimental and simulated concentrations, obtaining 3.79%(w/v) for NaCl and 5.66%(w/v) of KCl in static brine. In stirring brine, the errors obtained were 5.40%(w/v) for NaCl and 6.01%(w/v) for KCl. The resulting main diffusion coefficients were 1.12 × 10−9 (m2/s) for NaCl and 0.91 × 10−9 (m2/s) for KCl.