Characterization of flavor modulating effects in complex mixtures via high temperature liquid chromatography.

The identification of flavor modulating compounds, for example, bitter masking or sweet enhancing compounds, in complex mixtures such as botanical extracts or food preparations is difficult and time- and work-intensive. To accelerate this process, an improved screening method was developed on the basis of the separation of complex matrixes by the so-called LC Taste setup and subsequent comparative sensory analysis. The eluent containing only water and ethanol was diluted with a basic tastant solution (500 mg L(-1) caffeine and 5% sucrose, respectively) and evaluated by a trained panel by duo comparison tests. This novel method was applied to the known flavor and taste modulating substances homoeriodictyol (1), sterubin (2), hesperetin (3), and lactisol (9) as well as to simple mixtures of homoeriodictyol (1), sterubin (2), and hesperetin (3). To evaluate the potential of the method for more complex matrixes, the protocol was applied to plant extracts from Yerba Santa (Eriodictyon californicum) and honeybush tea (Cyclopia intermedia). The flavor modulating activities reported for homoeriodictyol (1), sterubin (2), and hesperetin (3) could be confirmed in these complex mixtures.