The effects of normal and controlled atmosphere combinations on tuber components responsible for acrylamide formation were studied during prolonged storage at 9 +/- 1 degrees C using the tubers of "Agria" and "Russet Burbank." The effects of low-dose irradiation (50, 200 Gy) prior to normal atmosphere storage were also studied. There was only a limited increase in the concentrations of sugars during 6 month of storage under normal atmosphere conditions. Low-dose irradiation slightly decreased the rate of sweetening in the tubers. The potential of acrylamide formation remained almost the same; however, the loss of firmness became clearer during 6 month of storage under normal atmosphere conditions. Controlled atmosphere storage in which O-2 was deficient to a sufficient respiration increased the concentrations of sugars, and thus, the potential of acrylamide formation in potatoes upon frying at 170 degrees C for 10 min. The sum of glucose and fructose concentrations showed a good correlation (r(2) similar to 0.90) with the potential of acrylamide formation for both cultivars.