A Simple Approach to Determine Diffusion Coefficient of Salt in Various Food

5 different types of foods are studied, and their diffusion coefficients of salt are experimentally determined with a simple and low-cost method. The foods which are studied include potato, sweet potato, pumpkin, taro, and radish. We pre-cut the foods into a spherical shape with known diameters and then brine them into the pre-mixed salt solution. After a certain soaking time, the ball-shaped piece is taken out and cut out a small piece from its center. A compact salt meter (LAQUAtwin-salt-11) made by Horiba was used to determine the salt concentration. The salt concentration at the center of the piece was measured as the diameter or the soaking time is used as variables. We then fit the measured data with the simulation. We are able to determine the following diffusion coefficient data with good matching between the measurement data and the simulation results. Furthermore, the diffusion coefficient of salt in potatoes was also measured at 100°C. The activation energy is thus determined to be around 74meV or 7.13 kJ/mol.