Identification of the major drivers of 'phenolic' taste in ... - GWRDC

AWRI: Identification Of The Major Drivers Of ‘Phenolic’ Taste In White Wines
both alcohol (r= 0.37) and residual sugar (RS) content (r= 0.56), while the winemakers’ perception of
quality was negatively correlated with alcohol (r= -0.46), and was unrelated to residual sugar content (r=
0.03). Therefore it appears that consumers considered the basic wine matrix components were important
in determining their liking of the wine, while winemakers saw alcohol level and phenolic levels as being
important in their quality assessments of white wines.
Correlation Coefficient (r)
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1.0
0.8
0.6
0.4
0.2
0.0
-0.2
-0.4
-0.6
-0.8
-1.0
Alcohol pH TA RS A280 A320
Consumer liking Winemaker score
Figure 4-2: Correlations between consumer liking, winemaker quality score and basic wine
composition of 24 commercial white wines.
Relating Winemaker perception of quality to composition
The predictive power of the PLS model relating winemaking score to compositional variables was also
not significant (p=0.395). This was either due to the exclusion of important compositional variables that
influenced quality, or that the winemakers lacked specific criteria in assessing such a diverse range of
wines. When only Riesling wines were considered, there was a substantial improvement in the predictive
power of the PLS model using the same compositional variables (p=0.001). This suggests that winemaker
assessment of quality was more reliable when they were able to apply a specific set of style based criteria.
Using alternative approaches: 1) the proportion of winemakers who thought that the wine tasted
‘phenolic’ was correlated against wine composition (Table 4-3), and 2) individual winemaker yes/no
responses to ‘phenolic taste’ were modelled against the quality score that they assigned.