Interaction of volatiles, sugars, and acids on perception of tomato aroma and flavor descriptors

To better understand the effect of sugars and acid levels on perception of aroma volatiles, intensity of tomato earthy/medicinal/musty, green/grassy/viney, and fruity/floral aroma and flavor descriptors were evaluated using coarsely chopped partially deodorized tomato puree. This puree was spiked with 1.5% to 3% sugar (glucose/fructose combinations), 0.1% to 0.2% acid (citric/malic acid combinations), or water and 2 levels of 12 individual food-grade volatiles reported to contribute to tomato flavor. A panel consisting of 6 to 8 trained members rated 9 aroma, 8 taste, and 1 aftertaste descriptors of the spiked and nonspiked purees. The panelists detected significant differences (P < or = 0.1) for various individual aroma compound/sugar/acid combinations for a range of descriptors. Adding 0.2% acids alone to bland tomato puree decreased green and floral aromas as well as sweet taste. Adding 3% sugars alone increased green and musty aromas and decreased floral aroma as well as sour, citrus, and bitter tastes. Principal component analysis (PCA) explained 56.5% of the variation in the first 3 principal components (PCs) for added acids and volatiles to bland tomato puree. The effect of added acids with the various aroma compounds generally increased perception of overall and ripe tomato taste and aroma, tropical aroma, and sour taste, and decreased sweet, fruity, and bitter tastes. PCA for added sugars with volatiles explained 67.8% of the variation in first 3 PCs, and sugars generally decreased perception of sour, bitter, and citrus tastes and green aroma, while enhancing perception of flavors associated with ripe, tropical, and aromatic tomatoes. Adding sugars, acids, and volatiles together had a similar effect to addition of sugars alone.