Identification of predominant odorants in Thai desserts flavored by smoking with "Tian Op", a traditional Thai scented candle

"Tian Op", a traditional Thai scented candle, is used for the smoking and flavoring of sweets, cakes, and other desserts for the purpose of adding a unique aroma to the final product. Gas chromatography-olfactometry, aroma extract dilution analysis, and GC-MS were applied to identify the potent odorants in two types of traditional Thai desserts ("num dok mai" and "gleep lum duan") prepared using a Tian Op smoking process. On the basis of the results of AEDA and calculated odor-activity values, the predominant odorants in the Tian Op flavored desserts were vinyl ketones (C ₅-C₉), n-aldehydes (C₅-C₁₁), (E)-2-unsaturated aldehydes (C₈-C₁₁), and ω-1-unsaturated aldehydes (C₈ and C₉). Sensory studies of model mixtures confirmed the importance of n-aldehydes, ω-1-unsaturated aldehydes, and guaiacol as predominant odorants; however, the results showed that vinyl ketones and (E)-2-unsaturated aldehydes, despite having high odor-activity values, may be of only minor importance in the typical aroma profiles of traditional Tian Op smoked desserts.