Numerical Solution of the Equations of Salt Diffusion into the Potato Tissues

Fick's second law equations for unsteady state diffusion of salt into the potato tissues were solved numerically. The set of equations resulted from implicit modeling were solved using Thomas method to find the salt concentration profiles in solid phase. The needed effective diffusivity and equilibrium distribution coefficient were determined experimentally. Cylindrical samples of potato were infused with aqueous NaCl solutions of 1-3% concentrations, and variations in salt concentrations of brine were determined over time. Solute concentrations profiles of samples were determined by measuring salt uptake of potato slices. For the studied conditions, equilibrium distribution coefficients were found to be dependent on salt concentrations, whereas the effective diffusivity was slightly affected by brine concentration.

Authors:

• Behrouz Mosayebi Dehkordi
• Frazaneh Hashemi
• Ramin Mostafazadeh

Keywords:

• Brine
• Diffusion
• Diffusivity
• Modeling
• Potato

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