Reducing bitter taste through perceptual constancy created by an expectation

The influence of a perceptual expectation, based on the first bite of a model product, on the perception of the taste of subsequent bites is investigated for bitter taste. A model product (chocolate ice cream) consisting of three regions of differing concentrations of a bitter compound (theobromine) was evaluated by a sensory panel using a multiple-bite Time-Intensity (TI) method. TI bitterness parameters were compared to those obtained with the model product containing the same amount of bitter compound but distributed homogeneously through the product. The relevant parameters of the resulting TI bitterness curves, i.e. the area under the curve, the time to return to zero, the overall maximum intensity, show that when the first bite is of a low bitter intensity, the perception of subsequent regions in the product assimilate towards a lower perceived bitterness intensity.