AbstractPresence of Formic Acid in Irradiated Maize Starch. Formic acid occurs in relatively large amounts during gamma irradiation of maize starch (100 μg/g/Mrad, in oxygen). It represents the main part of radio‐induced free acidity. We determined the influence of several parameters: irradiation conditions (dose, dose rate, temperature, surrounding gas), storage temperature, starch characteristics (moisture, impurities), heat treatment. A formation process is prospos