USING TIME-INTENSITY ANALYSIS TO EVALUATE THE BITTER TASTE OF BEVERAGES PREPARED FROM CONILON COFFEE (Coffea canephora) AND ARABICA COFFEE (Coffea arabica)

In the roasted and ground coffee industry, it is common to mix coffees of different species, such as arabica and conilon, which can give the beverage a different flavor. However, these blends can alter the sensory quality of the product. The classic descriptive sensory analysis restricts the evaluator's sensory response to a value that represents an average or integration of perception throughout the ingestion of the product, not allowing a satisfactory measure of the temporal evolution of sensory stimuli. Thus, time-intensity analysis was used to assess the change over time in the intensity of the bitter taste of the beverage due to the presence of arabica coffee, conilon or blend of these species. Three coffee samples were analyzed: 100% arabica, blend with 11.05% conilon in arabica and 100% conilon. The sample with 11.05% conilon refers to the detection threshold of conilon in arabica coffee (DT), determined in preliminary studies. Ten judges were selected and trained, and evaluated the coffee samples using SensoMaker® program. The results were analyzed by ANOVA and Tukey's test. The 100% conilon beverage had the highest means for the area under the curve (area), the total duration of the stimulus (Ttotal) and maximum intensity of the stimulus (Imax). For Ttotal and area, 100% arabica had the lowest means. The 11.05% conilon and 100% arabica beverages did not differ (p> 0.05) regarding Imax. The three coffee samples did not differ regarding the time to reach the maximum intensity (TImax). These results show the variation of the bitter taste when using conilon in the beverage. Studying the beverage prepared at the DT concentration level, the evaluators noticed the difference in relation to 100% arabica coffee, however this difference was not due to a change in the intensity of the attribute, but rather due to a greater residual bitter taste of coffee (Ttotal and area). However, the trend was that, by increasing the conilon concentration in the beverage, there was also an increase in the intensity of the bitter taste. Consequently, this addition of conilon coffee also increased the residual bitter taste in the beverage.