Potassium Sorbate Diffusivity in American Processed and Mozzarella Cheeses

The diffusivity of potassium sorbate in cheeses was determined by using diffusion models and computer programming for examining the residual surface concentration and the penetration of surface-applied potassium sorbate into cheese. To determine diffusivity, the concentration of potassium sorbate in sliced cheese was measured by penetration time and distance from surface. The diffusivity was calculated by nonlinear regression with experimental data based on Fick's law. The diffusivity of potassium sorbate through American processed cheese was 1.31∞10^-6 cm²/sec and for Mozzarella cheese 6.74∞10^-7 cm²/sec. This indicated that Mozzarella cheese would maintain surface concentration of potassium sorbate above the critical fungistatic level two times longer than American processed cheese.