Modeling of Sulfur Dioxide Uptake in Pre‐Peeled Potatoes of Different Geometrical Shapes

Sulfur dioxide uptake by pre‐peeled potatoes from dipping solutions was mathematically modeled. Diffusive mass transfer equations in porous medium were experimentally verified; residual levels of sulfur dioxide were measured in the range of industrial operating conditions. Effects of sodium bisulfite solution concentration, immersion time, size, shape, dry matter, density and velocity of the product were analyzed. Three geometric approximations to pre‐peeled potato cuts were examined (spheres, cubes and parallelepipeds). The fitting of equations to experimental data determined the effective diffusion coefficient of sulfur dioxide in potato tissue, which was compared to theoretical predictions in terms of molecular diffusivity, total solids content and tortuosity factor.