The changes in fatty acid compositions of the each fraction of oil, that is, steryl ester, triglyceride, diglyceride and free fatty acid, were analyzed during the storage of sesame seed for 4, 9, and 15 months at four different storage conditions, that is, storage under light with linen pouch(LA), storage in dark with linen pouch(DA), storage under light with poly ethylene pouch(LS), and storage in dark with poly ethylene pouch(DS).
In the fatty acid composition of steryl ester fraction, palmitic and stearic acid were decreased but linoleic acid was increased during the storage in all the storage conditions.
The ratio of C_(18) to C_(16) fatty acids in steryl ester from DA and LA was higher than that from DS and LS during storage until 15 months.
The palmitic and stearic acid content in triglyceride were decreased until 9 months of storage, then slightly increased until 15 months of storage in all the storage conditions, but reverse tendency was observed in the lineoleic acid content.
The ratio of C_(18) to C_(16) fatty acids and unstaturated to saturated fatty acids in DS were slightly higher than these in DA and LA.
In the fatty acid composition of free fatty acid, the content of palmitic and stearic acid were decreased until 9 months of storage, then increased until 15 months, but reverse tendency was observed in the oleic and linoleic acid: the ratio of unsaturated to staturated fatty acids in DA and LA was higher than that in DS and LS during the storage for 15 months.
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