Abstract: The off-flavour compounds of irradiated bread were detected with a combinated method of solid phase microextraction (SPME) and gas chromatography-mass spectroscopy (GC-MS) methodology. The effects of irradiation on producing off-flavor compounds of bread with different improved treatments were also investigated. Results showed that the main volatile com-pounds of irradiated bread are 1,3-bis(1,1-dimethylethyl)-benzene, ethyl octanonate, hexanal, 2-pentyl-furan, etc. In all these components, the kinds and the contents of aromatic hydro-carbon, aldehydes, alkyls and alkenes increased significantly. Their mutual effects were likely to be responsible for the off-flavour of the irradiated bread. With the reduction of irradiation dosage, the contents of main off-flavour compounds decrease markedly, but the effects of other improved treatments are insignificant.

Key words: irradiation, bread, off-flavor, treatment