| Abstract
| - The flavor of fennel fruits and fennel tea was examined by aroma extract dilution analysis of therespective dichloromethane extracts. In both fennel fruits and tea, trans-anethole, anisaldehyde, andtrans-4,5-epoxy-2(E)-decenal showed high flavor dilution (FD) factors followed by fenchone, 1,8-cineole, (R)-α-pinene, estragole, and β-myrcene. On the basis of these results, the odorants showinghigher FD factors were quantified in tea as well as in fruits, and odor activity values (OAV) in teawere calculated by dividing the concentration of the compound by its recognition threshold in water.The highest OAV was found for trans-anethole, followed by estragole, fenchone, 1,8-cineole, (R)-α-pinene, β-myrcene, and anisaldehyde. From a comparison of the concentrations of odorants infruits and tea, trans-anethole and estragole showed similar extraction rates of approximately 10−15%, whereas the extraction rates for (R)-α-pinene, β-myrcene, and limonene were below 2%. Incontrast to this, fenchone, camphor, linalool, and carvone showed higher extraction rates (26−50%),whereas the high apparent extraction rates of anisalcohol (393%) and vanilline (480%) were attributedto the formation from precursors. Sensory studies of aqueous models containing odorants in theamounts quantified in fennel teas revealed high similarity of the models with the tea and proved thatall impact odorants had been identified in their correct concentrations. Further sensory experimentsshowed that estragole had no odor impact on the overall flavor of fennel tea, and, therefore, a reductionof estragole in fennel products would have no negative impact on their sensoric quality. In contrastto this, trans-anethole and fenchone were found to be character impact compounds of fennel. Keywords: Aroma extract dilution analysis; estragole; fennel; fennel tea; odor activity value
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