Table 2.
Color, phenolic parameters and volatile composition of Vintage Port wine stored under different cellar conditions and bottle orientation for 44 months in bottle (n = 5).
| Parameters/ Volatiles |
Months | Cellar A | Cellar B | Statistical Differences | Descriptor (Olfactory Threshold) | |
|---|---|---|---|---|---|---|
| Vertical | Horizontal | Horizontal | ||||
| b* | T = 0 | 28 | 28 | 28 | - | - |
| 6 | 16.0 (6.6) | 19.7 (3.1) | 21.1 (3.7) | n.s. | ||
| 15 | 26.4 (2.6) | 26.6 (0.9) | 26.4 (1.3) | n.s. | ||
| 44 | 19.1 (0.7) | 18.2 (2.1) a | 25.1 (13.7) a | * | ||
|
Hue
(Abs 420 nm/Abs 520 nm) |
T = 0 | 0.58 | 0.58 | 0.58 | - | - |
| 6 | 0.74 (0.08) | 0.79 (0.05) | 0.70 (0.04) | n.s. | ||
| 15 | 0.64 (0.06) | 0.61 (0.02) | 0.63 (0.03) | n.s. | ||
| 44 | 0.72 (0.06) | 0.65 (0.14) a | 0.78 (0.06) a | ** | ||
| Total Proanthocyanidins (g/L) | T = 0 | 3.2 | 3.2 | 3.2 | - | - |
| 6 | 2.8 (0.3) | 3.1 (0.3) | 3.3 (0.2) | n.s. | ||
| 15 | 2.9 (0.3) a | 3.5 (0.3) a | 3.3 (0.2) | * | ||
| 44 | 1.3 (0.5) | 1.3 (0.1) | 0.8 (0.5) | n.s. | ||
| Tannin Specific Activity (NTU/mL) | T = 0 | 404 | 404 | 404 | - | |
| 6 | 392.1 (10.6) a | 360.8 (13.0) a | 375.1 (12.5) | ** | ||
| 15 | 361.1 (9.4) | 342.1 (12.0) | 347.8 (19.3) | n.s. | ||
| 44 | 411.1 (17.2) a, b | 471.5 (29.2) a | 436.3 (15.3) b | *** | ||
| Furfural (µg/L) | T = 0 | 137 | 137 | 137 | - | Toasty, caramel (14 µg/L) |
| 6 | 207.6 (73.7) | 227.0 (97.8) | 308.0 (118.2) | n.s. | ||
| 15 | 298.2 (26.4) a | 359.0 (92.2) b | 461.4 (43.3) a, b | **** | ||
| 44 | 521.4 (90.0) a | 471.3 (93.0) b | 914.1 (42.7) a, b | **** | ||
| 5-Methylfurfural (µg/L) | T = 0 | NQ | NQ | NQ | - | Spicy, toasty (16 µg/L) |
| 6 | NQ | NQ | NQ | - | ||
| 15 | NQ | NQ | NQ | - | ||
| 44 | 43.5 (2.0) a | 42.8 (2.8) b | 64.5 (3.9) a, b | **** | ||
| Benzaldehyde (µg/L) | T = 0 | 45 | 45 | 45 | - | Bitter almonds (2 mg/L) |
| 6 | 34.4 (10.4) | 35.7 (8.3) | 33.9 (8.8) | n.s. | ||
| 15 | 16.3 (1.9) | 17.4 (1.0) a | 15.0 (0.2) a | * | ||
| 44 | 32.7 (4.7) a, b | 25.4 (2.9) a, b | 28.9 (3.0) a | * | ||
| Phenylethyl acetate (µg/L) | T = 0 | NQ | NQ | NQ | - | Floral, sweet (250 µg/L) |
| 6 | NQ | NQ | NQ | - | ||
| 15 | 14.6 (1.3) | 16.0 (0.8) a | 13.2 (1.3) a | ** | ||
| 44 | 32.2 (1.1) | 32.8 (1.7) | 30.8 (1.2) | n.s. | ||
Results expressed as an average (standard deviation) of three readings for each bottle. Identical letters indicate statistically significant differences among samples stored under different cellar conditions and bottle orientation within the same post-bottling period. n.s. p > 0.05, * p ≤ 0.05, ** p ≤ 0.01, *** p ≤ 0.001, **** p ≤ 0.0001, NQ not quantified.