Tocopherol degradation in wheat germ oil was studied during storage at different temperatures. Two types of wheat germ were used: heat-treated germ (HT) and raw germ (RG). The oil was extracted (Soxhlet, n-hexane) and stored at 25 and 47 degrees C (82 days) and at -20 and 5 degrees C (600 days). Tocopherols were determined by HPLC. Total tocopherol, -tocopherol, and -tocopherol decreased following first-order kinetics. At 25 and 47 degrees C, the values of the degradation rate constants for total tocopherol were 5.00x10(-3) days(-1) (RG), 3.00x10(-3) days(-1) (HT), and 5.37 x10(-2) days(-1) (RG), 2.57x10(-2) days(-1) (HT), respectively, indicating an increase in tocopherol degradation rate with increasing temperature. The reaction rates of total tocopherol were similarly affected at 5 and -20 degrees C, with lower rate constants (4x10(-4) and 2x10(-4) days(-1), respectively). -tocopherol degraded faster than -tocopherol, presenting higher rate constants. Low temperatures favour the preservation of tocopherols.