Comparison of an Electronic Nose Based on Ultrafast Gas Chromatography, Comprehensive Two-Dimensional Gas Chromatography, and Sensory Evaluation for an Analysis of Type of Whisky
Table 4
Key chemical compounds (variables), which are important for sample discrimination.
Number of variables-column number
Name of the compound
Scotch
Irish
Bourbon
1-1
2-Propanol
+
+
+
2-1
n-Butanol
+
+
+
3-1
Furfural
+
+
+
4-1
Ethyl isovalerate
−
+
+
5-1
Alpha-pinene
+
+
+
6-1
Decanal
+
+
+
7-1
Eugenol
+
+
+
8-1
Geosmin
+
+
+
9-1
Gamma-decalactone
+
+
+
10-1
12-Methyltridecanal
+
+
+
1-2
n-Butanol
+
+
+
2-2
Furfural
+
−
+
3-2
1-Octanol
−
−
+
4-2
Decanal
+
+
+
5-2
2,4-Nonadienal
+
+
+
6-2
Phenylethyl acetate
+
+
+
7-2
(E,E)-2,3-Decadienal
+
+
+
8-2
4-Vinylguaiacol
−
−
+
9-2
Geosmin
+
+
+
10-2
Gamma-nonalactone
−
−
+
11-2
Gamma-decalatone
+
+
+
“+” means that the compound was considered as variable for the chosen group. “−” means that the compound was not considered as variable for the chosen group.