GC-MS IDENTIFICATION OF VOLATILE COMPOUNDS EVOLVED BY DRY SEEDS IN RELATION TO STORAGE-CONDITIONS

In order to identify the volatile compounds which were evolved from five types of dry seeds under different storage conditions and also released from them after heating, experiments were carried out using a GC-MS fitted with a cryo-condensation system. Fifty-nine types of volatile components were identified, of which the major components were methanol, ethanol, acetone, isopropanol, 2-butanone and various aldehydes, such as acetaldehyde, 2-methylpropanal, 2- and 3-methylbutanal, pentanal and hexanal. Regardless of the storage temperature, the seeds stored at high relative humidity (RH) contained more iso-type aldehydes, such as 2-methylpropanal and 2- and 3-methylbutanal, whereas n-type aldehydes, such as pentanal, hexanal and heptanal, were evolved abundantly from seeds stored at low RHs. Acetaldehyde, the most universal and abundant aldehyde in the seeds, was emitted at different levels depending on the seed species and the storage RH. The endogenous aldehydes of dry seeds appear to be causally related to seed ageing during storage.