Changes in Functional Factors of Sesame Seed and Oil during Various Types of Processing

Sesame seed and oil have long been used as a representative health food, and recently, various important physiological activities of sesame lignans have been elucidated. Most sesame foods are produced by roasting at about 150 °C to develop characteristic flavor and taste. The sesame oil from seeds roasted at 180-200 °C have a characteristic flavor and brown-red color, and are very stable against oxidative deterioration. Sesame salad oil from unroasted seeds is commonly purified, and is also stable against oxidation. Among lignans, sesamin was stable in roasting and almost no change occurred even at 200°C, while sesamolin decomposed mostly to give sesamol, especially in deep frying. The marked antioxidative activity of deep-roasted oil was shown to be caused by the multi-synergistic effects of Maillard-type roasted products, γ-tocopherol, sesamol, and sesamin. A very interesting fact is that sesamolin was changed effectively to sesaminol, a newly discovered antioxidative lignan, during the decolorization process of unroasted sesame oil. The deep-roasted sesame flavor concentrates containing various alkylpyrazines showed marked antithrombosis activity. Sesame lignans, antioxidative factors, and also characteristic flavor components could be extracted specifically by supercritical CO 2 extraction from sesame seed or oil.