## 2 Materials and Methods
### Beer Quality Traits
#### 2.6.3 Sensory Analysis  
Beers were evaluated by a trained panel (16 assessors: 8 females and 8 males, age 25-60) of the CREA Research Centre for Viticulture and Enology (Asti). The sensory tests were carried out in a tasting room (ISO norms 8589-2007). Beer samples (50 mL) were identified with a 3-digit code and poured in tasting glasses (ISO 3591-1977). The tetrad test was utilized to discriminate the two samples, according to their similarity [15]. \begin{table}
\begin{tabular}{l l l l l l l l} \hline \hline
**KI 1** & **MW 2** & **Compound** & **Main Fragments 3** & \(\mathbf{A_{u}}\)**4** & **CAS\_L** & \multicolumn{2}{c}{\(\mathbf{A_{u}}\)4**} & **CAS\_T** \\ \hline  & & & & & & & **AV** & **ST DEV** & **AV** & **STD DEV** \\ \hline
780 & 100 & Hexanal & 56(100), 44(100), 41(90), 57(90),42(50), & 2.0 & 0.1 & 3.5 & 0.1 \\
853 & 98 & (_E_)-2-Hexrenal & 41(100), 55(90), 69(90), 83(80), 98(30) & 1.5 & 0.1 & 3.8 & 0.9 \\
939 & 136 & \(\alpha\)-Pinen & 93(100), 77(30), 12(20), 105(20), 136(20) & 0 & 0 & 2.4 & 3.3 \\
980 & 136 & \(\beta\)-Pinen & 93(100), 69(25), 41(25), 79(25), 121(20), & 38.6 & 9.4 & 112.9 & 6.3 \\
990 & 136 & \(\beta\)-Myrcene & 93(100), 69(50), 41(50), 79(15), 53(15), & 1287.8 & 67.2 & 2127.9 & 71.1 \\
1032 & 158 & Amyl & 43 (100), 70 (80) 71 (70) 55 (30) 89 (20) & 4.2 & 0.5 & 10.9 & 0.6 \\
1036 & 136 & Limonene & 93(100), 68(50), 77(40), 136(30), 121(20) & 24.7 & 3.0 & 54.6 & 1.6 \\
1040 & 136 & \(\beta\)-Cycmene & 93(100), 91(50), 79(40), 78(35), 77(30), & 6.1 & 1.0 & 6.1 & 0.2 \\  & & & 136(10) & & & & & \\
1085 & 154 & Linalool & 17(100), 93(85), 41(50), 55(45), 80(40), & 53.3 & 7.3 & 91.8 & 1.1 \\
1217 & 152 & Methyl & 120(100), 92(60), 152(50), 121(30), 65(15) & 10.9 & 1.7 & 13.7 & 0.2 \\  & & salicate & Methyl & 74(100), 87(50), 129(20), 141(20), 172 tr & 6.3 & 0.1 & 6.5 & 0.0 \\
1224 & 172 & monanoate & 69(100), 41(55), 93(10), 123(10), 154 tr & 7.7 & 0.6 & 22.4 & 0.2 \\
1250 & 154 & Geraniol & 69(100), 41(70), 84(30), 94(25), 137(25), & 10.4 & 2.2 & 11.9 & 0.2 \\
1277 & 152 & (Neral) & 152(10) & 58(100), 43(100), 71(90), 59(80), 85(10), 170 tr & 9.2 & 1.1 & 16.2 & 0.1 \\
1281 & 170 & 2-Undecanone & 74(100), 110(75), 55(50), 67(55), 152(50) & 28.8 & 1.2 & 37.4 & 0.1 \\
1291 & 184 & Methyl-(Z)-4-decenoate & 69(100), 41(40), 114(40), 123(30), 83(20), 182 & 12.8 & 1.1 & 43.3 & 0.5 \\
1300 & 182 & (_E_)-Methyl & 69(100), 41(40), 114(40), 123(30), 83(20), 182 & 69(100), 93(50), 41(50), 42(45), 80(20) & 6.7 & 0.3 & 8.5 & 0.1 \\
1360 & 196 & (Z-) & Geranyl acetate & 69(100), 43(45), 93(40), 121(25), 136(20), 196 & 69.9 & 0.9 & 70.5 & 0.9 \\
1380 & 196 & (_E_)- & tr & 93(100), 133(100), 79(70), 69(65), 204(10) & 652.8 & 28.2 & 677.8 & 5.3 \\
1411 & 204 & Caryophyllene & 161(100), 105(45), 91(40), 119(30), 133(10), & 27.0 & 1.8 & 31.2 & 0.3 \\
1437 & 204 & Germacrene D & 204(10) & 119(100), 93(95), 41(30), 107(35), 79(30), 204 & 30.1 & 1.7 & 37.3 & 0.1 \\
1438 & 204 & Bergamotene & tr & 93(100), 80(30), 121(30), 147(25), 107(20), & 1341.4 & 35.4 & 1510.4 & 11.6 \\
1445 & 204 & \(\alpha\)-Humulene & 204(10) & 161(100), 119(50), 105(55), 91(45), 79(40), & 73.2 & 4.0 & 83.9 & 1.1 \\
1450 & 204 & \(\beta\)-Salienne & 105(100), 93(95), 79(80), 121(60), 161(60), & 96.3 & 4.8 & 114.9 & 0.7 \\
1490 & 204 & \(\beta\)-Selienne & 204 (65) & 93(100),41(50), 69(50), 107(50), 79(45), & 21.4 & 0.8 & 25.1 & 0.4 \\
1500 & 204 & \(\alpha\)-Farnesene & 107(45), 204 (10) & & & & & \\ \hline \hline \end{tabular}  
* Kováts Index, calculated using a _n_-alkanes linear series; 2 Molecular Weight; 3 relative quantitation, assuming as 100 the most abundant fragment; 4 area units (area/10\({}^{6}\)).  
\end{table} 
Table 3: Compounds identified by GC-MS in CAS_T and CAS_L hop oils. The beer sensory profiles were realized by the same panel but with 14 assessors, as two subjects: one male (age 43) and one female (age 58) were not available, following a procedure derived from the ISO standards (11035-1994) and applied in wine [16; 17]. The first evaluation was a qualitative description of the products.