## 3 Results
### Sensory Analysis  
PCA performed on all the sensory data (Figure 3) showed that two principal components accounted for 74% of the total variance. PC1 explained well the time--evolution (49% of the variance), whereas PC2 (25% of the variance) seemed only partially to represent the separation by vinication, although its interpretation is less clear.  
In this PCA biplot, trends characterizing the scores and the effects on the variables (loadings) are shown. The descriptors that mostly contributed to W3 (at negative values of PC1), hence to the temporal trend by decreasing in time, were clarity, fresh vegetative aroma, off-odor and astringency. On the other hand, color intensity, floral aroma, cleanness, and bitterness described mostly W6 (negative values of PC2). Regarding W9, the sensory descriptors were sourness, saltness, sweetness, warmness, dried fruit, tropical fruit and apple aromas; thus, these variables contributed also substantially to the temporal trend (increasing over time from W3 to W9). Regarding the difference between the two vinications (V1 vs. V2) at W9 (after nine-month storage), the most relevant sensory descriptors characterizing V1 were tropical fruit aroma, apple aroma, and overall quality judgement. Instead, the most important sensory descriptors that characterized V2 (positive values of PC2) were olfactory intensity, spicy and pear aromas. Taking a look at the PCA considering each wine individually, it is possible to highlight that the wine V1 after nine months of storage (V1.W9) was evaluated with a high overall quality judgement and was described predominantly by the sensory descriptors tropical fruit and apple aromas as well as the absence of off-odor.  
To better investigate these trends, a two-way ANOVA was applied on all the sensory variables used in the PCA biplot (Table S6). The aim was to assess the main effect of each independent variable (time and unification) but also if there was any interaction between them (time \(\times\) unification). The ANOVA showed that floral, tropical fruit and cleanness were statistically different for the unification factor. Considering the factor time, the sensory descriptors different were floral, tropical fruit, dried fruit and fresh vegetative aromas, warmness, sweetness, sourness, saltness, and overall judgement. Finally, considering the interaction, only floral aroma was found significative. This showed an interesting relation with the results shown in Figure 2 for the volatile compounds analyzed by GC-MS: V1 appeared to be the wine with a faster evolution into the bottle, indicated by the separation it showed from previous months and from V2.W9; in fact, V2 evolved as well as from W6 to W9 but more slowly than V1. However, according to the sensory profile, the two wines at W9 are characterized by rather different descriptors, a possible effect of the different operations performed over the vinicitation styles. In addition, further studies are necessary using other set of Pinot blanc wines under the same vinicitation conditions to firmly confirm the differences found in this study.  
Figure 3: Principal component analysis (PCA) on sensory profile data of Pinot Blanc wines. V: unification type (1: control wine, 2: wine variant), W: time over storage (months).