The paper presents a study of the influence of the conditions applied during differential scanning calorimetry (DSC) measurements (concentration and heating rate) on the possible detection of the differences between gelatinization occurring in both non-irradiated and irradiated potato starch with a dose of 20kGy. Differences in gelatinization of irradiated and non-irradiated potato starch during DSC analysis was attributed to the radiation induced destruction of crystalline ordering. This was confirmed by studies of the samples irradiated to very high doses (446 and 600kGy), and by comparing with the effect of grinding. Changes of starch properties caused by radiodepolymerization-contrary to those caused by grinding-influences gelatinization behaviour much more than the WAXS crystallinity in solid state.