ABSTRACT
The perception of aroma and taste, that is, the ‹avor of a given food, is induced by bioactive molecules interacting with chemoreceptor proteins located in the nose and on the tongue, respectively. On the basis of current knowledge in ‹avor research, the presence of certain structural elements (olfactophores, gustophores) as well as speci c concentrations exceeding the sensory thresholds is an important prerequisite of the molecules to become “‹avor-active.” Moreover, it is well accepted today that not a single ‹avor impact molecule, but a combinatorial code of multiple odor-and taste-active key compounds, each in its speci c concentration, is needed to re‹ect the typical aroma and taste pro le of a given food. Thus, comparing ‹avor with
18.1 Introduction .................................................................................................. 413 18.2 Why Research on Food Flavors? .................................................................. 417 18.3 Why Is the Combinatorial Code of Aroma and Taste of Foods Often
Unknown? ..................................................................................................... 418 18.4 Aroma Compounds in Black Tea Infusions .................................................. 420
18.4.1 Differences in Odorant Composition between Black Tea Leaves and Tea Beverage .............................................................................. 426
18.5 Taste Compounds in Black Tea Infusions .................................................... 428 18.5.1 Identi cation of Taste-Active Molecules .......................................... 428 18.5.2 Quanti cation of Taste Compounds and Calculation of
Dose-over-Threshold Factors ............................................................ 432 18.5.3 Taste Recombination ........................................................................ 432 18.5.4 Modulation of Caffeine Bitterness by Flavonol-3-O-Glycosides ..... 433
References .............................................................................................................. 436
sound perception, it is not a single instrument, but it is the instrumental ensemble of an orchestra and the well-balanced interplay between the single instruments that make music a unique experience. Thus, the number and the concentrations of such bioactive constituents determine whether, for example, a wine has an enjoyable overall ‹avor or whether it has developed an awful cork taint.
