# Exploitation of Three Non-Conventional Yeast Species in the Brewing Process
## 3 Results
### Fermentation Trials with the Selected Non-Saccharomyces Yeasts
#### 3.2.3 Main Volatile Compounds
\begin{table}
\begin{tabular}{c c c c c c} \hline  & _Z. flowertinia_ DiSVA & **US05 + DISVA** & **US05 + DISVA** & **US05 + DISVA** & **S. cerevisiae** \\  & **263** & **263 1.1** & **263 1.10** & **263 1.20** & **US-05** \\ \hline \multicolumn{5}{c}{**Esters**} \\ Ethyl butyrate & 0.02 \(\pm\) 0.014 \({}^{\rm c}\) & 0.01 \(\pm\) 0.00 \({}^{\rm c}\) & 0.064 \(\pm\) 0.014 \({}^{\rm b}\) & 0.140 \(\pm\) 0.014 \({}^{\rm a}\) & 0.042 \(\pm\) 0.014 \({}^{\rm b}\) \\ Ethyl acetate & 1.6 \(\pm\) 0.1 \({}^{\rm b}\) & 8.33 \(\pm\) 0.04 \({}^{\rm a}\) & 7.7 \(\pm\) 2.1 \({}^{\rm a}\) & 6.7 \(\pm\) 5.0 \({}^{\rm a}\) & 2.6 \(\pm\) 0.2 \({}^{\rm b}\) \\ Phenyl ethyl acetate & 0.17 \(\pm\) 0.017 \({}^{\rm d}\) & 0.317 \(\pm\) 0.01 \({}^{\rm b}\) & 0.26 \(\pm\) 0.0 \({}^{\rm c}\) & 0.09 \(\pm\) 0.02 \({}^{\rm b}\) & 0.45 \(\pm\) 0.01 \({}^{\rm a}\) \\ Ethyl hexanoate & 0.00 \(\pm\) 0.00 \({}^{\rm c}\) & 0.09 \(\pm\) 0.02 \({}^{\rm b}\) & 0.08 \(\pm\) 0.00 \({}^{\rm b}\) & 0.02 \(\pm\) 0.00 \({}^{\rm c}\) & 0.22 \(\pm\) 0.03 \({}^{\rm a}\) \\ Isoamyl acetate & 0.30 \(\pm\) 0.01 \({}^{\rm a}\) & 0.34 \(\pm\) 0.02 \({}^{\rm a}\) & 0.23 \(\pm\) 0.01 \({}^{\rm b}\) & 0.33 \(\pm\) 0.04 \({}^{\rm a}\) & 0.190 \(\pm\) 0.01 \({}^{\rm b}\) \\ \hline \multicolumn{5}{c}{**Alcohols**} \\ n-Propanol & 14.0 \(\pm\) 3.0 \({}^{\rm b}\) & 19.44 \(\pm\) 0.36 \({}^{\rm a}\) & 18.9 \(\pm\) 1.9 \({}^{\rm a}\) & 19.9 \(\pm\) 0.3 \({}^{\rm a}\) & 17.8 \(\pm\) 0.3 \({}^{\rm c}\) \\ Isobutanol & 6.9 \(\pm\) 3.1 \({}^{\rm b}\) & 11.25 \(\pm\) 1.34 \({}^{\rm a}\) & 10.2 \(\pm\) 0.3 \({}^{\rm b}\) & 11.8 \(\pm\) 0.3 \({}^{\rm a}\) & 9.5 \(\pm\) 0.3 \({}^{\rm a}\) \\ Amylic alcohol & 3.49 \(\pm\) 2.7 \({}^{\rm b}\) & 7.85 \(\pm\) 0.17 \({}^{\rm a}\) & 7.9 \(\pm\) 0.7 \({}^{\rm a}\) & 7.8 \(\pm\) 1.0 \({}^{\rm a}\) & 7.9 \(\pm\) 0.2 \({}^{\rm a}\) \\ Isoamylic alcohol & 20.42 \(\pm\) 1.34 \({}^{\rm c}\) & 43.53 \(\pm\) 3.21 \({}^{\rm a}\) & 4.10 \(\pm\) 1.6 \({}^{\rm a}\) & 4.13 \(\pm\) 0.3 \({}^{\rm a}\) & 37.23 \(\pm\) 1.8 \({}^{\rm b}\) \\ \(\beta\)-Phenyl ethanol & 1.74 \(\pm\) 0.144 \({}^{\rm e}\) & 3.94 \(\pm\) 0.001 \({}^{\rm c}\) & 4.17 \(\pm\) 0.007 \({}^{\rm b}\) & 2.78 \(\pm\) 0.001 \({}^{\rm d}\) & 7.29 \(\pm\) 0.00 \({}^{\rm a}\) \\ \hline \multicolumn{5}{c}{**Carbonyl compounds**} \\ Acetaldehyde & 14.2 \(\pm\) 1.9 \({}^{\rm d}\) & 51.63 \(\pm\) 9.74 \({}^{\rm c}\) & 56.9 \(\pm\) 0.9 \({}^{\rm b}\) & 68.8 \(\pm\) 0.014 \({}^{\rm b}\) & 84.9 \(\pm\) 7.03 \({}^{\rm a}\) \\ \hline \multicolumn{5}{c}{**Terpens**} \\ Linalol & 0.051 \(\pm\) 0.014 \({}^{\rm b}\) & 0.124 \(\pm\) 0.028 \({}^{\rm a}\) & 0.129 \(\pm\) 0.007 \({}^{\rm a}\) & 0.041 \(\pm\) 0.001 \({}^{\rm b}\) & 0.114 \(\pm\) 0.007 \({}^{\rm a}\) \\ \(\alpha\)-terpineol & 0.094 \(\pm\) 0.028 \({}^{\rm a}\) & 0.078 \(\pm\) 0.006 \({}^{\rm a}\) & 0.088 \(\pm\) 0.001 \({}^{\rm a}\) & 0.077 \(\pm\) 0.015 \({}^{\rm a}\) & 0.058 \(\pm\) 0.001 \({}^{\rm a}\) \\ Citronello & 0.401 \(\pm\) 0.020 \({}^{\rm c}\) & 0.402 \(\pm\) 0.073 \({}^{\rm c}\) & 0.263 \(\pm\) 0.022 \({}^{\rm b}\) & 0.237 \(\pm\) 0.026 \({}^{\rm d}\) & 0.781 \(\pm\) 0.014 \({}^{\rm a}\) \\ \hline \multicolumn{5}{c}{Data are the means \(\pm\) standard deviation. Data with different superscript letters (\({}^{\rm a,b,c,d}\)) within each row are significantly different (Duncan tests; \(p<\) 0.05).} \\ \end{tabular}
\end{table} 
Table 4: The main by-products and volatile compounds in the beers produced by _Z. flowertinia_ in the pure and mixed fermentations (mg/L). \begin{table}
\begin{tabular}{c c c c c} \hline  & _L. thermotolerans_ & **US05 + DISVA** & **US05 + DISVA** & **US05 + DISVA** & _S.