The aims of the present study were to analyze the most important chemical reactions between sodium hydroxide and potato constituents involved in potato chemical peeling, and to measure the apparent diffusivity of NaOH in potato skirt and flesh separately, as a function of temperature and NaOH concentration, selected according to potato chemical peeling process. Chemical reaction of the suberin of the potato skin with NaOH was proposed as the most important one to promote chemical peeling. Whereas starch hydrolysis, middle lamella dissolution and cell wall disruptions were proposed as the principal chemical reactions in flesh. Experiments to determine NaOH apparent diffusivities in skin and flesh were performed following a cell diffusion method at 25, 40, 50, 60 and 70 degrees C temperatures and concentrations of 4, 12 and 20 g NaOH/100 g of solution. Finally, correlation equations were determined to describe apparent diffusivity dependence on temperature and concentration.