## 3 Results
### Total Polyphenol and Flavonoid Content  
The phenolic and flavonoid contents of the beer and hop extract samples are shown in Tables 5 and 6, respectively. Total polyphenols ranged from 27.4 to 49.8 mg GAE/g of dried hops and from 228.7 to 292.0 mg GAE/100 mL of beer. Total flavonoids varied between 6.3 and 22.0 mg QE/g of dried hops and between 3.1 and 5.8 mg QE/100 mL of beer. Among hop extracts, TPE showed the highest amount of polyphenols while PCJe had the highest amount of flavonoids. CCHe hop was found to be the poorest in both polyphenols and flavonoids (Table 5). Among the beers, ACD was the richest in both classes of compounds. LKO beer exhibited a higher amount of polyphenols than IPA beer and both possessed similar flavonoid content (Table 6).  
\begin{table}
\begin{tabular}{c c c c c c c} \hline \hline \multirow{2}{*}{**N\({}^{\circ}\)**} & \multirow{2}{*}{**COMPONENT 1**} & \multirow{2}{*}{**LRI 2**} & \multirow{2}{*}{**LRI 3**} & \multirow{2}{*}{**IPA(\%)**} & \multirow{2}{*}{**LKO(\%)**} & \multirow{2}{*}{**ACD(\%)**} \\ \cline{1-1}  & & & & & & \\ \hline
1 & 3-methyl-1-butanol & 738 & 740 & 2.5 \(\pm\) 0.03 & 9.6 \(\pm\) 0.03 & 8.2 \(\pm\) 0.02 \\
2 & 2-methyl-1-butanol & 741 & 744 & 1.2 \(\pm\) 0.02 & 3.5 \(\pm\) 0.03 & 3.6 \(\pm\) 0.03 \\
3 & isoamyl acetate & 875 & 877 & 1.8 \(\pm\) 0.02 & 3.0 \(\pm\) 0.01 & 5.2 \(\pm\) 0.02 \\
4 & hethly hexanoate & 980 & 981 & 1.1 \(\pm\) 0.02 & 3.5 \(\pm\) 0.03 & 2.4 \(\pm\) 0.03 \\
5 & \(\beta\)-myrce & 987 & 989 & 2.0 \(\pm\) 0.02 & - & 7.7 \(\pm\) 0.02 \\
6 & linalool & 1094 & 1095 & 0.8 \(\pm\) 0.03 & - & - \\
7 & 2-phenyl ethanol & 1100 & 1102 & 0.6 \(\pm\) 0.02 & 4.5 \(\pm\) 0.02 & 3.9 \(\pm\) 0.01 \\
8 & caprylic acid & 1174 & 1178 & 2.4 \(\pm\) 0.02 & 8.8 \(\pm\) 0.02 & 13.3 \(\pm\) 0.02 \\
9 & hexyl octanoate & 1196 & 1198 & 8.0 \(\pm\) 0.02 & 32.9 \(\pm\) 0.07 & 23.7 \(\pm\) 0.01 \\
10 & phenylethyl acetate & 1230 & 1229 & 1.7 \(\pm\) 0.02 & 0.8 \(\pm\) 0.02 & 4.1 \(\pm\) 0.01 \\
11 & 2-methyl-2-pentenoic acid & 1254 & * & 0.3 \(\pm\) 0.02 & - & - \\
12 & capric acid & 1375 & 1373 & 0.7 \(\pm\) 0.02 & 6.9 \(\pm\) 0.04 & 10.5 \(\pm\) 0.02 \\
13 & ethyl decanoate & 1398 & 1396 & 2.8 \(\pm\) 0.02 & 23.4 \(\pm\) 0.02 & 15.3 \(\pm\) 0.06 \\
14 & ethyl dodecanoate & 1596 & 1593 & 0.9 \(\pm\) 0.03 & 3.1 \(\pm\) 0.02 & 2.1 \(\pm\) 0.02 \\
15 & palmitic acid & 1977 & 1973 & 73.2 \(\pm\) 0.06 & - & - \\  & SUM & & 100.0 & 100.0 & 100.0 \\  & Monoterpenes & & 2.8 & - & 7.7 \\  & Fatty Acids & & 89.4 & 78.6 & 67.3 \\  & Other & & 7.8 & 21.4 & 25.0 \\ \hline \hline \end{tabular}  
* The components are reported according to their elution order on a polar column; 2 Linear Retention Indices measured on apolar column; 3 Linear Retention indices from literature;
* LRI not available; IPA: Percentage mean values of “Ipagea” beer components (%); LKO: Percentage mean values of “Lokomotive” beer components; ACD: Percentage mean values of “Accademia” beer components (%); ; : Not detected; tr: traces (mean value \(<\) 0.1%).  
\end{table}
Table 4: Chemical composition (percentage mean value \(\pm\) standard deviation) of vapor phase beer samples.  
\begin{table}
\begin{tabular}{c c c} \hline \hline \multirow{2}{*}{**Hops**} & \multicolumn{2}{c}{**Total Polyphenols**} & \multicolumn{2}{c}{**Total Flavonoids**} \\  & **(mg GAE/g Dried Hops)** & **(mg QE/g Dried Hops)** \\ \hline STGe & 35.5 \(\pm\) 0.5 & 17.7 \(\pm\) 0.0 \\ HBKe & 27.4 \(\pm\) 0.4 & 15.3 \(\pm\) 0.1 \\ HLBe & 32.0 \(\pm\) 0.0 & 18.8 \(\pm\) 0.0 \\ CCHe & 23.0 \(\pm\) 0.0 & 6.3 \(\pm\) 0.1 \\ PCJe & 37.0 \(\pm\) 0.1 & 22.0 \(\pm\) 0.1 \\ PCe & 30.8 \(\pm\) 0.1 & 16.9 \(\pm\) 0.1 \\ TPE & 49.8 \(\pm\) 0.5 & 20.6 \(\pm\) 0.1 \\ \hline \hline \end{tabular}  
* HSTGe: “Stytrian Golding” hop extract; HBKe: “Hersbrucker” hop extract; HLBe: “Hallertau Blanc” hop extract; CCHe: “Cascade Cryo Hops” hop extract; PCJe: “Pacifica” hop extract; PCe: “Pacifica” hop extract; TPE: “Topazz” hop extract.  
\end{table}
Table 5: Polyphenols and flavonoids of hop extract samples.