o e r rThe thermal decomposition of ferulic acid has been studied by thermal gravimetric analysis. The decomposition products were separated by gasliquid chromatography and identified by GLC retention time and infrared spectral comparison with authentic materials. Combined gas-liquid chromatography-mass spectrometry and thin-layer chromatography were used as supplementary tools in product analysis.Unsubstituted, 4-methyl-, 4-ethyl-, and 4-vinylguaiacols were identified as products from the decomposition of ferulic acid in air and nitrogen atmospheres. Vanillin, acetovanillone (4-hydroxy-3-methoxyacetophenone), and vanillic acid were formed only in the air atmosphere. A mechanism is proposed for a portion of the ferulic acid decomposition.ardwood smoke used to cure food products consists of a variety of compounds-carbonyls, acids,