Figure 1. Multivariate analysis output showing the first two factors. The upper plot shows Factors 1 and 2 for the 16 wines. The lower plot shows Factors 1 and 2 for the descriptors in the various conditions: O = Olfactive; G = Global; N = Nose-clip; NZ = New Zealand participants’ data; F = French participants’ data.
classification). We undertook extensive physico-chemical measures for each wine, including estimates of organic acids, pH, TA, reducing sugars, ethanol, free and total sulphur dioxide, determination of concentrations of thiols and other sulphur compounds, fermentation-derived volatile aroma compounds, methoxypyrazines, and transition metal elements. The sensory and physico-chemical data will be associated via multivariate analyses to provide information about the relation between perceived subcomponents of minerality (i.e., the sensory
Lincoln University chemists (left to right): Brett Robinson, Rob Sherlock, Jason Breitmeyer.
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data) and wine composition (i.e., the physical and chemical measures) as a function of wine country of origin. These results will be reported in a second article to follow at a later date.
Results: Sensory data Sorting task: The Sorting Task data showed that both French and NZ participants in general differentiated French Sauvignons from NZ Sauvignons. However, there were a few exceptions: For French participants, a Loire wine (FLPC) associated more closely with NZ wines whilst a NZ wine (NZSVCH – Clos Henri)
associated more closely with French wines. For the New Zealand participants, several wines from Loire and Sancerre (FSHB; FLCH; FLPC) associated more closely with the New Zealand wines and a NZ wine NZSVA (Ara) associated more closely with French wines than it did with other NZ wines. Wine descriptor ratings: Analyses of variance (ANOVAs) were conducted on the descriptor ratings with subject origin and wine as factors. Overall, wines from New Zealand were rated as significantly sweeter, more fruity, and with more green characters than the French wines. On the other hand, French wines were rated as more bitter, and as lower on fresh/ zingy, familiarity, and liking than the NZ wines. Wines from NZ and France were rated similarly in intensity of perceived mineral, as well as in intensity of assumed sub-components of mineral (e.g., flinty/smoky; chalky/calcareous). Our hypothesis was not supported in that French wines on average were not rated significantly higher in “mineral” than NZ wines. Of particular importance was the finding that there was a significant wine effect of mineral in all three conditions, Olfactive (smelling only), Global (full ‘tasting’), and Nose-clip (inhibition of aroma). The significant effect of the descriptor “mineral” when judged by bouquet only supports the notion that minerality can be smelled. Not only did participants discriminate different intensities of minerality across the 16 wines in the nose-only condition, but the Olfac-