DIFFUSIVITY OF CARBON-DIOXIDE THROUGH THE SKIN AND FLESH OF RUSSET BURBANK POTATO-TUBERS

The diffusion coefficient of CO2 in 'Russet Burbank' potato (Solanum tuberosum L.) tubers was determined under steady-state conditions at 10 and 27C. The data showed that the skin is the main barrier to gas diffusion, with an average diffusion coefficient of 6.57 x 10(-7) and 7.61 x 10(-7) cm.s-1 at 10 and 27C, respectively. The flesh also presents an appreciable barrier to gas diffusion. The average diffusion coefficient of CO2 in the flesh was 2.00 x 10(-4) and 2.24 x 10(-4) cm.s-1 at 10 and 27C, respectively. Under regular storage conditions, the tuber is well aerated and the concentration of O2 at the center of the tuber is sufficient to maintain aerobic respiration.