The Verification of the Usefulness of Electronic Nose Based on Ultra-Fast Gas Chromatography and Four Different Chemometric Methods for Rapid Analysis of Spirit Beverages

Table 4

Compounds detected in whiskey samples.

Name	RT/LTPRI1	RT/LTPRI2	LTPRI1 LIT	LTPRI2 LIT	Descriptor
(E)-2-Decanal	73.93/1260	74.36/1370	1262	1371	Green, orange, and tallowy
(E)-2-Heptenal	51.87/967	54.44/1068	960	1062	Almond, earthy, grossy, and sulfurous
(Z)-3-Hexen-1-ol	41.95/851	45.39/949	852	960	Mossy, green, and fresh
(Z)-3-Hexen-1-ol, butanoate	62.83/1173	67.05/1252	1187	1256	Banana, green, and winey
(Z)-3-Hexenyl isobutyrate	64.91/1133	64.39/1211	1144	1208	Apple, etheral, sweet, and winey
(Z)-4-Heptenal	46.43/903	48.33/986	900	988	Creamy, sweet, and boiled potato
(Z)-Whisky lactone	76.94/1305	84.64/1550	1316	1548	Coconut
1-Hexanol	44.01/875	48.67/991	870	980	Dry, floral, grossy, green, woody, and fruity
1-Hexen-3-ol	34.00/772	38.82/865	775	850	Green
2, 4, 5-Trimethylthiazole	54.21/995	54.50/1069	996	1073	Earthy, hazelnut, moldy, and chocolate
2-Methyl-1-butanol	31.68/735	37.41/849	739	852	Fruity and malty
2-Methyl-1-propanol	23.13/628	28.76/740	628	735	Alcoholic, bitter, and winey
2-Methylfuran	21.06/601	22.64/652	602	639	Burnt, solvent, metallic, and musty
2-Methylphenol	57.98/1043	69.35/1288	1054	1283	Phenolic
3, 5-Octadien-2-one	61.96/1093	64.00/1205	7092	1203	Fruity and mushroom
3-Heptanone	45.39/891	46.91/968	888	969	Cinnamon, green, spicy, and sweet
4-Ethylguaiacol	74.66/1271	77.35/1421	1282	1430	Floral, spicy, and phenolic
6-Decenal	70.20/1206	70.60/1308	1203	1294	Green
Benzaldehyde	50.37/950	55.86/1088	959	1086	Almond, woody, and burnt sugar
Beta-ionone	88.65/1487	88.71/1623	1490	1627	Floral, woody, and raspberry
Beta-phellandrene	56.63/1026	52.75/1045	1030	1059	Fruity, minty, and herbaceous
Beta-pinene	52.71/977	48.79/992	979	994	Green, pine, sweet, and resin
Butanoic acid	38.50/812	46.84/967	816	970	Rancid, sweaty, and butter
Carvone	73.14/1249	75.94/1397	1253	1386	Minty and peppermint
Diethyl ether	16.70/476	16.90/524	491	532	—
Ethanol	15.14/432	18.28/566	437	564	Alcoholic
Ethyl acetate	22.16/615	24.05/675	609	673	Acidic, etheral, fruity, and orange
Ethyl butyrate	37.34/799	38.92/867	799	864	Banana, fruity, sweet, and acetonic
Furfural	40.86/839	47.61/977	827	972	Almond, bread, and sweet
Geosmin	85.91/1444	83.15/1523	1430	1513	Beet and earthy
Hexyl acetate	55.27/1009	55.80/1087	1011	1082	Citrus, fruity, green, and spicy
Hexyl butyrate	69.27/1193	68.18/1270	1191	1257	Apple, fruity, and green
Indole	76.04/1291	84.64/1550	1295	1549	Burnt, earthy, floral, and jasmine
Limonene	56.63/1026	53.13/1051	1033	1061	Citrus, fruity, minty, and peely
Methyl butanoate	29.59/711	31.73/778	717	784	Ester, etheral, green, and sweet
n-Butanol	26.00/655	31.69/774	651	778	Fermented and fruity
p-Cresol	60.18/1071	71.60/1325	1072	1312	Phenolic and smoky
Pentanol	33.68/757	38.87/867	767	879	Anise, fruity, and green
Propyl acetate	28.76/701	31.38/774	708	775	Fruity, ketonic, sweet, and solvent
Terpinolene	61.36/1086	58.04/1118	1088	1112	Fruity, pine, herbaceous, and sweet
tert-Butylmethylether	20.35/551	20.28/596	546	600	—

RT1: retention time in column 1 (MXT-5);
LTPRI1: linear temperature-programmed retention index for compounds from column 1;
RT2: retention time in column 2 (MXT-1701);
LTPRI2: linear temperature-programmed retention index for compounds from column 2;
LTPRI1 LIT: linear temperature-programmed retention index for compounds from column 1 from literature;
LTPRI2 LIT: linear temperature-programmed retention index for compounds from column 2 from literature.
The positive identification of selected compounds was highlighted in bold font.