Relationships between consumer preference, flavor attributes and chemical compounds of Vidalia onion

The chemical compounds and flavor attributes of two Vidalia onion varieties (Nunhems 1006 sweet variety; Sapelo hot variety) grown at different fertilizer levels were analyzed to investigate their influence on flavor perception. The first part of this study consisted of the descriptive sensory analysis and chemical analyses of sugars (HPLC), lachrymatory factor (LF; propanethial S-oxide) and methyl thiosulfinates (GC-FID/FPD). The lachrymatory sensation and pungency/aftertaste were significantly correlated with the LF and methyl thiosulfinate content attributing the majority of Vidalia onion flavor, whereas sugars had little impact. In the second study, the relationship between consumer flavor preferences and chemical composition were defined. Samples containing low content of the LF (LF < 1.806 mol/g) and methyl thiosulfinates were perceived as less pungent, and also preferred by the majority of consumers. Partial least squares (PLS) regression and agglomerative hierarchical clustering (AHC) revealed consumer segmentations with different preference patterns in the population tested.