CHEMICAL-CHANGES IN STORED TOASTED CRUDE CANOLA AND SESAME SEED OILS

'Alto' canola seed and sesame seed were roasted at 180, 200, 220, 240, and 260C, for 8 min or 10 min. As temperature increased, minor change s in fatty acid composition were observed Darkness and blueness in can ola oil increased with toasting temperatures up to 240C, and then decr eased. The darkness, greenness and yellowness of sesame seed oil incre ased with increasing toasting temperature. The overall color of canola oil was significantly darker than that of sesame seed oil (alpha less than or equal to 0.05). 2-Thiobarbituric acid (TBA) numbers for both oils increased as toasting temperature increased. TBA numbers of the c anola oil increased with extended storage time up to 4 weeks and then decreased. For sesame seed oil, TBA numbers also were influenced by st orage rime, but less change was observed than for canola oil. 2-Thioba rbituric acid reactive substances (TBARS) content of canola oil was si gnificantly higher than that for sesame seed oil when TBA numbers were compared to the same treatment.