Table 2.
Concentration of volatile compounds (μg/L) in control and red wines containing GL added pre- or post-fermentation in 28 L ferments.
| Compound | Control | PRE 1 | PRE 2 | PRE 4 | POST 1 | POST 4 | Sig | Aroma Detection Threshold (μg/L) |
|---|---|---|---|---|---|---|---|---|
| ethyl acetate | 3793.6 ± 2330.8b | 7018.5 ± 604.1ab | 8252.6 ± 1258.8a | 7755.0 ± 998.4a | 7374.0 ± 1810.3ab | 8016.4 ± 561.9a | 0.021 | 15,000 ** a |
| ethyl butanoate | 26.1 ± 4.6 | 23.9 ± 2.2 | 25.9 ± 2.1 | 26.3 ± 1.3 | 29.4 ± 2.2 | 27.9 ± 2.8 | 0.292 | 20 ** a |
| ethyl-2-methylbutanoate | 0.5 ± 0.0 | 0.5 ± 0.0 | 0.5 ± 0.0 | 0.5 ± 0.1 | 0.6 ± 0.1 | 0.5 ± 0.0 | 0.572 | 1 ** a |
| ethyl 3-methylbutanoate | 0.6 ± 0.1 | 0.6 ± 0.1 | 0.7 ± 0.1 | 0.7 ± 0.1 | 0.7 ± 0.1 | 0.7 ± 0.0 | 0.653 | 3 ** a |
| 3-methylbutyl acetate | 614.1 ± 28.3 | 609.5 ± 124.1 | 636.6 ± 37.5 | 502.2 ± 6.9 | 563.3 ± 69.0 | 539.0 ± 41.9 | 0.156 | 30 ** a |
| ethyl hexanoate | 60.3 ± 3.2 | 65.6 ± 3.2 | 60.8 ± 2.0 | 58.0 ± 6.3 | 66.2 ± 10.4 | 58.0 ± 5.6 | 0.381 | 14 ** b |
| hexyl acetate | 32.3 ± 2.4 | 30.8 ± 5.6 | 29.0 ± 6.3 | 26.5 ± 3.6 | 29.9 ± 7.4 | 25.7 ± 2.7 | 0.603 | 670 ** a |
| ethyl lactate | 5186.6 ± 494.4 | 5165.3 ± 551.4 | 5637.1 ± 565.7 | 5458.7 ± 1000.1 | 5742.9 ± 1164.8 | 5776.8 ± 366.6 | 0.845 | 146,000 ** a |
| ethyl octanoate | 15.7 ± 0.9 | 15.8 ± 1.0 | 16.8 ± 1.6 | 18.0 ± 0.2 | 16.5 ± 1.8 | 15.8 ± 1.2 | 0.235 | 20 ** b |
| ethyl decanoate | 28.5 ± 4.5 | 33.2 ± 3.9 | 41.2 ± 10.0 | 46.8 ± 6.2 | 35.3 ± 10.9 | 31.8 ± 6.2 | 0.093 | 200 ** b |
| diethyl succinate | 1.4 ± 0.0 | 1.6 ± 0.0 | 12.2 ± 1.9 | 19.0 ± 13.6 | 10.8 ± 7.4 | 11.0 ± 3.3 | 0.052 | 1,250,000 ** a |
| 2-phenylethyl acetate | 21.2 ± 1.6 | 21.2 ± 5.1 | 20.8 ± 4.3 | 20.8 ± 3.2 | 16.4 ± 1.7 | 17.0 ± 1.5 | 0.277 | 250 ** a |
| 1-propanol | 9029.4 ± 732.8 | 8357.8 ± 570.6 | 7802.2 ± 770.4 | 8692.7 ± 616.2 | 9394.5 ± 277.2 | 9215.7 ± 589.7 | 0.066 | 500 ** b |
| 2-methyl-1-propanol | 2362.3 ± 161.8 | 2258.3 ± 231.4 | 2190.4 ± 24.5 | 2102.6 ± 46.6 | 2083.8 ± 57.4 | 2136.8 ± 30.3 | 0.107 | 40,000 ** b |
| 1-butanol | 64.3 ± 10.5 | 60.3 ± 11.2 | 67.3 ± 9.6 | 50.8 ± 8.5 | 71.5 ± 8.1 | 61.1 ± 13.3 | 0.29 | 150,000 * a |
| 3-methyl-1-butanol | 17185.2 ± 765.4 | 16411.5 ± 351.2 | 17774.1 ± 515.1 | 16513.6 ± 2882.3 | 17612.4 ± 256.5 | 16733.9 ± 560.0 | 0.69 | 30,000 ** a |
| 1-hexanol | 199.5 ± 13.8 | 194.7 ± 24.7 | 199.8 ± 14.9 | 193.7 ± 14.6 | 209.7 ± 7.0 | 211.1 ± 4.3 | 0.598 | 8000 ** a |
| Linalool | 6.2 ± 0.6 | 6.7 ± 0.7 | 6.7 ± 0.3 | 7.0 ± 1.2 | 7.6 ± 0.9 | 6.8 ± 0.4 | 0.427 | 15 ** a |
| 1-octanol | 2.4 b ± 0.1 | 2.4 ± 0.2ab | 2.6 ± 0.1ab | 2.8 ± 0.2a | 2.6 ± 0.0ab | 2.6 ± 0.1ab | 0.041 | 0.7 ** a |
| α-terpineol | 5.0 ± 0.4 | 5.2 ± 0.1 | 5.6 ± 0.8 | 6.1 ± 0.9 | 5.4 ± 0.3 | 5.1 ± 0.5 | 0.267 | 250 ** b |
| benzyl alcohol | 178.3 ± 18.7 | 179.5 ± 23.3 | 173.8 ± 22.7 | 166.1 ± 18.4 | 178.2 ± 11.7 | 159.9 ± 8.9 | 0.715 | 200,000 *** a |
| 2-phenylethanol | 1443.4 ± 123.0b | 1587 ± 180.3ab | 1545.8 ± 250.5b | 1985.5 ± 162.7a | 1356.9 ± 21.6b | 1354.5 ± 26.4b | 0.002 | 14,000 ** b |
| Limonene | 0.4 ± 0.0b | 0.5 ± 0.0a | 0.6 ± 0.0a | 0.6 ± 0.0a | 0.6 ± 0.1a | 0.6 ± 0.1a | 0.034 | 15 ** a |
| Nonanal | 2.8 ± 0.0 | 2.8 ± 0.0 | 2.8 ± 0.1 | 2.9 ± 0.1 | 2.9 ± 0.1 | 2.8 ± 0.1 | 0.461 | 2.5 ** a |
| 3-methylbutanoic acid | 45.6 ± 0.6bc | 44.1 ± 2.2c | 47.3 ± 0.7bc | 50.7 ± 1.1a | 47.5 ± 0.7ab | 47.4 ± 1.2bc | 0.001 | 33 * a |
| hexanoic acid | 702.9 ± 29.9c | 788.8 ± 13.1b | 849.5 ± 46.4ab | 887.5 ± 12.0a | 779.1 ± 43.6bc | 848.0 ± 4.8ab | <0.001 | 420 ** b |
| octanoic acid | 1448.5 ± 87.3a | 1392.1 ± 185.5a | 1301.6 ± 112.0ab | 1240.0 ± 67.6ab | 1072.4 ± 71.6b | 1181.0 ± 48.5ab | 0.009 | 500 ** b |
| decanoic acid | 375.7 ± 33.1a | 362.5 ± 13.2a | 330.7 ± 28.0abc | 341.0 ± 13.1ab | 293.3 ± 24.7bc | 271.4 ± 26.2c | 0.001 | 1000 ** b |
| β-damascenone | 24.1 ± 7.4 | 20.7 ± 6.2 | 28.7 ± 2.9 | 21.8 ± 5.2 | 22.9 ± 4.0 | 25.7 ± 6.3 | 0.561 | 0.05 ** a |
Mean values ± standard deviation of the three fermentation replicates. Bolded p-values indicate significant differences based on one-way ANOVA. Lower-case letters indicate significant differences between samples based on LSD post hoc comparison, p < 0.05). Prefixes: PRE = GL extracts added prior to fermentation, POST = GL extracts added after fermentation process. * Refers to Mayr et al. [47], ** Refers to Wang et al. [20], *** Refers to Zhao et al. [48]. Thresholds were reported for aqueous ethanol (a) and wine matrix (b).