# Discrimination of Smoke-Exposed Pinot Noir Wines by Volatile Phenols and Volatile Phenol-Glycosides
## 2 Results and Discussions
### Correlation of Glycos to the Free and Total Form of VPs  
Correlation analysis was performed to evaluate potential connections between VPs and putative VP-glycoses. The correlation heatmap and matrix for 35 tentative annotated VP-glycoses and the VPs (free-form and total) were plotted using [PERSON]'s correlation analysis (Figure 4). The correlation matrix identifies positive or negative correlations between different compounds--values range from 1 (darkest red) to \(-\)1 (darkest blue). The results showed that VPs and VP-glycoses were all positively correlated (Table S4), with nearly 60% of the correlations being statistically significant (\(p<0.05\)). For example, H-P-guaiacol vs. free-form guaiacol (r = 0.77, \(p\) = 2.50 \(\times\) 10\({}^{-8}\)), H-P-guaiacol vs. total guaiacol (r = 0.78, \(p\) = 6.60 \(\times\) 10\({}^{-8}\)), H-P-guaiacol-iso1 vs. free-form guaiacol (r = 0.65, \(p\) = 2.36 \(\times\) 10\({}^{-5}\)), and H-P-guaiacol-iso1 vs. total guaiacol (r = 0.71, \(p\) = 2.19 \(\times\) 10\({}^{-6}\)) showed the strong correlation in agreement with the findings [18]. The positive correlations indicated the potential interaction among their biosynthetic pathways, converting the VP to VP-glycoses.  
However, the closest relationships were among free-form and bound-form VPs, as indicated by the dark red square at the bottom right of the heat map (Figure 4). In addition, strong correlations were also observed between the VP-glycoses, such as syringyl-\(\beta\)-D-glucopyranoside vs. H-guaiacol (r = 0.92), syringyl-\(\beta\)-D-glucopyranoside vs. P-H-cresol (r = 0.92), syringyl-\(\beta\)-D-glucopyranoside vs. H-P-4-methylguaiacol (r = 0.92), H-guaiacol vs. P-H-cresol (r = 0.94), and H-guaiacol vs. H-P-4-methylguaiacol (r = 0.90).  
\begin{table}
\begin{tabular}{c c c c} \hline \hline  & **Tentative Glycos** & **Fold-Change (FC)** & **Raw \(p\)-Value** \\ \hline
1 & H-P-4-Methylguaiacol-Iso & 4.58 & 2.37 \(\times\) 10\({}^{-8}\) \\
2 & Deoxyhexose-P-4-Ethylguaiacol & 2.88 & 2.59 \(\times\) 10\({}^{-8}\) \\
3 & Deoxyhexose-H-Cresol-Iso & 2.97 & 3.02 \(\times\) 10\({}^{-8}\) \\
4 & H-H-P-4-Ethylguaiacol & 7.39 & 6.61 \(\times\) 10\({}^{-8}\) \\
5 & Syringyl-\(\beta\)-D-Glucopyranoside-Iso & 4.08 & 9.50 \(\times\) 10\({}^{-8}\) \\
6 & H-4-Methylguaiacol & 2.69 & 1.26 \(\times\) 10\({}^{-7}\) \\
7 & H-4-Methylguaiacol-Iso2 & 2.11 & 2.52 \(\times\) 10\({}^{-7}\) \\
8 & H-Guaiacol & 7.88 & 3.95 \(\times\) 10\({}^{-7}\) \\
9 & P-H-Cresol-Iso2 & 3.90 & 5.13 \(\times\) 10\({}^{-7}\) \\
10 & Syringyl-\(\beta\)-D-Gentiobioside-Iso1 & 2.60 & 8.96 \(\times\) 10\({}^{-7}\) \\
11 & H-H-P-4-Ethylguaiacol-Iso1 & 31.88 & 2.21 \(\times\) 10\({}^{-5}\) \\
12 & P-H-Cresol-Iso3 & 3.52 & 3.23 \(\times\) 10\({}^{-5}\) \\
13 & H-P-4-Methylguaiacol & 2.66 & 4.37 \(\times\) 10\({}^{-5}\) \\
14 & Deoxyhexose-H-Cresol & 3.13 & 5.73 \(\times\) 10\({}^{-5}\) \\
15 & Syringyl-\(\beta\)-D-Gentiobioside & 5.65 & 8.64 \(\times\) 10\({}^{-5}\) \\ \hline \hline \end{tabular} Abbreviations: H—Hexose, P—Pentose, Iso—Isomer.  
\end{table}
Table 1: Univariate fold change analysis of top 15 volatile phenol glycosides identified from non-smoke-exposed and smoke-exposed wines.