Sweetness Enhancement by Aromas: Measured by Descriptive Sensory Analysis and Relative to Reference Scaling

Sweetness enhancement by aromas has been suggested as a strategy to mitigate sugar reduction in food products, but enhancement is dependent on type of aroma and sugar level. A careful screening of aromas across sugar levels is thus required. Screening results might, however, depend on the method employed. Both descriptive sensory analysis and relative to reference scaling were therefore used to screen 5 aromas across 3 sucrose concentrations for their sweetness-enhancing effects in aqueous solutions. In the descriptive analysis, samples with added vanilla, honey, and banana aroma were rated as significantly sweeter than samples with added elderflower or raspberry aroma at all sucrose concentrations. In relative to reference scaling, honey aroma significantly increased the sweet taste compared with samples with added elderflower or no aroma at low and medium sucrose concentrations. Banana and raspberry aromas also increased the sweet taste significantly compared with the sample with added elderflower aroma at medium sucrose concentration in the relative to reference scaling. This demonstrates that the cross-modal effects observed by the 2 methods were different. In terms of the methods applied, relative to reference scaling was generally found to result in a decrease in the measured sweetness enhancement by aromas. In the descriptive analysis, the cross-modal effect of aromas on sweet taste perception was found to be significantly higher at 2.5% and 5.0% w/w sucrose compared with 7.5% w/w sucrose. These results highlight the importance of considering how references are employed in sensory analysis and how they affect cross-modal interactions.