## 3 Materials and Methods
### Fermentation Experiments  
Three different winemaking methods were used in this study (classical white-winemaking, classical red-winemaking and carbonic maceration methods). Muscat Hamburg grapes were hand-harvested in 2014. For the classical white-winemaking method, the Muscat Hamburg grapes were immediately destemmed and gently crushed. Musts were clarified by cold-settling for 18 h at 10 degC to separate the clear juice from the sediment and the loading volume was about 90% of the tank capacity. \begin{table}
\begin{tabular}{c c c c c c} \hline \hline \multirow{2}{*}{**Attributes**} & \multirow{2}{*}{**Class**} & \multicolumn{4}{c}{**Type of Wine**} & \multirow{2}{*}{**Significance b**} \\ \cline{3-3} \cline{5-6}  & & **W** & & **R** & **CM** \\ \hline \multirow{2}{*}{Visual analysis} & Clarity (5) & 4.5 \(\pm\) 0.15 & 4.4 \(\pm\) 0.15 & 4.6 \(\pm\) 0.1 & — \\  & Appearance (10) & 8.5 \(\pm\) 0.15 & 8.1 \(\pm\) 0.2 & 8.2 \(\pm\) 0.1 & ** \\  & Aroma purity (6) & 5.3 \(\pm\) 0.1 & 5.1 \(\pm\) 0.15 & 5.5 \(\pm\) 0.15 & *** \\ Aroma analysis & Aroma intensity (8) & 6.8 \(\pm\) 0.15 & 5.8 \(\pm\) 0.15 & 7.3 \(\pm\) 0.2 & *** \\  & Aroma quality (16) & 12.1 \(\pm\) 0.15 & 11.5 \(\pm\) 0.15 & 13.5 \(\pm\) 0.2 & *** \\  & Taste purity (6) & 5.1 \(\pm\) 0.1 & 4.6 \(\pm\) 0.2 & 5.3 \(\pm\) 0.2 & *** \\ \multirow{2}{*}{Taste analysis} & Taste intensity (8) & 6.8 \(\pm\) 0.1 & 6.7 \(\pm\) 0.15 & 6.9 \(\pm\) 0.2 & — \\  & Taste prolongation (8) & 6.6 \(\pm\) 0.15 & 6.7 \(\pm\) 0.1 & 7.1 \(\pm\) 0.2 & * \\  & Taste quality (22) & 16.9 \(\pm\) 0.1 & 16.1 \(\pm\) 0.2 & 18.2 \(\pm\) 0.2 & *** \\ Global evaluation & Harmony (11) & 9.5 \(\pm\) 0.15 & 8.6 \(\pm\) 0.1 & 10.2 \(\pm\) 0.15 & *** \\ Total a  & 100 & 82.1 \(\pm\) 0.3 & 77.6 \(\pm\) 0.2 & 86.8 \(\pm\) 0.4 & *** \\ \hline \hline \end{tabular}  
* \(p\) \(<\) 0.05; ** \(p\) \(<\) 0.01; *** \(p\) \(<\) 0.001.  
\end{table} 
Table 4: Sensory analysis of Muscat Hamburg wines produced by different winemaking techniques. The fermentation temperature was 13-15 \({}^{\circ}\)C, and the alcoholic fermentation lasted for 12 days. In classical red-winemaking method, the Muscat Hamburg grapes were destemmed and subjected to a short cold maceration (4 h at 10 \({}^{\circ}\)C) prior to the winemaking process and the loading volume was around 80% of the tank capacity. The fermentation temperature was controlled at 25-28 \({}^{\circ}\)C. In addition, during the fermentation process, half of the total volume of wine was pumped over in air 1-3 times per day depending on the kinetics of the fermentation. After the alcoholic fermentation was complete (7 days), only free-run must was used for bottling. For the carbonic maceration process, the intact grapes with stems were placed into a stainless-steel tank that had been saturated with food-grade carbon dioxide and hermetically closed. The tanks were saturated with carbon dioxide every 12 h. The temperature was controlled at 28 \({}^{\circ}\)C for 12 days. After carbonic maceration, only the must obtained by gentle pressing was used for fermentation. The fermentation temperature was controlled at 13-15 \({}^{\circ}\)C, and the alcoholic fermentation lasted for 7 days. All grape must samples were treated with sulfur dioxide (sulfited) to a final concentration of 40 mg/L, and the final pH value of the must was adjusted to 3.3 by aseptically adding tartaric acid (85%, _w/v_). This organic acid was selected because it is normally found in grapes and wines and is rarely metabolized by ascomycetous yeasts. The initial yeast inoculums were 1 \(\times\) 10\({}^{6}\) cells/mL from cultures grown overnight in YPD medium (1% (_w/v_) yeast extract, 2% (_w/v_) peptone and 2% (_w/v_) glucose). All the fermentations were carried out in 25-L stainless-steel tanks with at least three replicates. A stainless-steel mesh screen was fixed at the bottom of the 25-L stainless-steel tank during the carbonic maceration process to separate the intact grapes from the must.