## 2 Results and Discussion
### Quantification of Polyfunctional Thiols in Commercial Wines  
Using the optimized method, the three polyfunctional thiols were measured in 31 California wines and 30 commercial New York State wines representing seven wine types: four _V. vinifera_ (Gewurztraminer, Riesling, Sauvignon blanc, Cabernet Sauvignon), one non-varietal _V. vinifera_ (rose blends), one _V. labruscana_ (Niagara), and one _Vitis_ spp. (Cayuga White). Results are summarized in Table 3. The only thiol detected in all wine samples was 3-MH, and concentrations were significantly higher in the _vinifera_-based wines than the interspecific hybrid-based wines (Cayuga White and Niagara). However, 3-MH concentrations were not significantly higher in Sauvignon blanc wines than the other white varietal wines, unlike results reported elsewhere [3]. \begin{table}
\begin{tabular}{c c c c c} \hline \hline \multirow{2}{*}{**Variety**} & \multirow{2}{*}{**Region**} & \multicolumn{3}{c}{**Concentration (ng/L)**} \\ \cline{3-5}  & & **4-MMP** & **3-MH** & **3-MHA** \\ \hline _Cayuga White_ & Finger Lakes, NY (\(n=5\)) & \(<\)LOD & 195 \(\pm\) 38 & \(<\)LOD \\ _Niagara_ & Finger Lakes, NY (\(n=5\)) & 18 \(\pm\) 13 & 230 \(\pm\) 159 & \(<\)LOD \\ _Riesling_ & Finger Lakes, NY (\(n=5\)) & 2.3 \(\pm\) 2.5 & 569 \(\pm\) 334 & \(<\)LOD \\ _Gewürztraminer_ & Finger Lakes, NY (\(n=5\)) & \(<\)LOD & 373 \(\pm\) 134 & \(<\)LOD \\ _Rosé_ & Finger Lakes, NY (\(n=5\)) & \(<\)LOD & 296 \(\pm\) 116 & a \\ \hline \multirow{4}{*}{_Sauvignon blanc_} & Finger Lakes, NY (\(n=5\)) & 27 \(\pm\) 8 & 446 \(\pm\) 154 & a \\  & Napa Valley, CA (\(n=4\)) & 44 \(\pm\) 22 & 438 \(\pm\) 87 & b \\  & Sonoma County, CA (\(n=4\)) & 43 \(\pm\) 18 & 712 \(\pm\) 342 & b \\  & Central Coast, CA (\(n=3\)) & 50 \(\pm\) 25 & 835 \(\pm\) 137 & b \\ \hline \multirow{4}{*}{_Cabernet Sauvignon_} & Napa Valley, CA (\(n=8\)) & \(<\)LOD & 765 \(\pm\) 396 & 57 \(\pm\) 16 \\  & Sonoma County, CA (\(n=5\)) & \(<\)LOD. & 405 \(\pm\) 106 & 60 \(\pm\) 21 \\ \cline{1-1}  & Central coast, CA (\(n=6\)) & \(<\)LOD & 498 \(\pm\) 113 & 67 \(\pm\) 24 \\ \cline{1-1}  & Lodi (\(n=1\)) & \(<\)LOD & 396 & 46 \\ \hline \hline \end{tabular}  
* Only one sample had detectable values: Rose = 52.3 ng/L and Sauvignon blanc = 33.8 ng/L. b Interference on quantifier ion prevented accurate quantification.  
\end{table} 
Table 3: Concentrations of volatile polyfunctional thiols in California and NY wines. Mean 3-MH concentrations were lower in New York and California Sauvignon blanc (less than 1000 ng/L) than reports from other regions. For example, a survey of commercial Sauvignon blanc wines from Australia, New Zealand, France, and South Africa reported mean concentrations ranging from 1700 to 7100 ng/L [24]. Mean concentrations of 3-MH in Sauvignon blanc in our survey were also lower than what was reported in an earlier survey of US Sauvignon blanc, \(\sim\)2000 ng/L for eight wines over 3 vintages [24], although the lack of specific information regarding wine region and large standard deviations (\(\sim\)100%) in the previous report makes direct comparison challenging. In contrast, mean 3-MH in New York Gewurztraminer and Riesling (373 and 579 ng/L, respectively) were in the middle of ranges reported for Australian sources of these varietal wines [26]. 3-MH in the California Cabernet Sauvignon was within the broad range reported for Bordeaux red wines previously (10-5000 ng/L) [27]. The contribution of volatile thiols like 3-MH to red wines has not been well studied, but the mean values reported in this study (396-765 ng/L) are comparable to other non-Sauvignon blanc white wines, both in the current study and elsewhere [26]. The reasons for lower concentrations of 3-MH in the California and New York State Sauvignon blanc in this study as compared to other reports is unclear, as several factors are known to affect final 3-MH concentrations.