The decomposition of ochratoxin A (OTA) was examined, under different temperature and moisture conditions. The calculated half-lives, corresponding to 50% values, were 707, 201, 12, and 6 min, respectively, at 100, 150, 200, and 250 degrees C for dry wheat and 145, 60, and 19 min, respectively, at 100, 150, and 200 degrees C for wheat heated under wet conditions. The presence of water (50%) increased the decomposition of OTA at 100 and 150 degrees C; the opposite was observed at 200 degrees C. Complete destruction of OTA within the limits of this study (100 to 250 degrees C) was not obtained.