Table 1.
Wine phenolic concentration, tannin composition and colour properties in Shiraz wines prepared following harvest time, saigneé and water addition treatments 12 months after fermentation †.
| Phenolic Measure | Unit | H-1 ‡ | DA-1 | RR-1 | RO-1 | H-2 | DA-2 | RR-2 | RO-2 | H-3 | ANOVA p Value |
|---|---|---|---|---|---|---|---|---|---|---|---|
| Total phenolics | (A.U.) | 24.43 ± 0.52 f | 32.74 ± 0.63 d | 32.95 ± 0.46 d | 38.79 ± 1.13 a | 28.38 ± 1.05 e | 34.62 ± 0.89 c | 33.91 ± 0.58 cd | 36.84 ± 0.91 b | 36.75 ± 0.52 b | <0.0001 |
| Colour measures | |||||||||||
| Colour density | (A.U.) | 7.64 ± 0.14 e | 10.58 ± 0.29 c | 10.73 ± 0.17 c | 12.64 ± 0.49 a | 9.47 ± 0.21 d | 11.03 ± 0.29 c | 10.85 ± 0.19 c | 11.82 ± 0.40 b | 11.75 ± 0.23 b | <0.0001 |
| Hue | Ratio | 0.54 ± 0.01 e | 0.57 ± 0.01 d | 0.56 ± 0.00 de | 0.66 ± 0.02 a | 0.54 ± 0.01 e | 0.59 ± 0.00 c | 0.59 ± 0.00 c | 0.64 ± 0.00 b | 0.64 ± 0.00 b | <0.0001 |
| Total Anthocyanin | (mg/L) | 340 ± 10.66 d | 442 ± 16.85 b | 452 ± 5.42 ab | 438 ± 27.84 b | 411 ± 10.62 c | 472 ± 10.71 a | 453 ± 9.1 ab | 439 ± 14.04 b | 438 ± 8.94 b | <0.0001 |
| Non-bleachable pigment | (A.U.) | 1.35 ± 0.12 e | 1.99 ± 0.09 c | 2.01 ± 0.08 c | 3.14 ± 0.26 a | 1.58 ± 0.05 d | 2.04 ± 0.10 c | 2.10 ± 0.03 c | 2.75 ± 0.07 b | 2.62 ± 0.05 b | <0.0001 |
| Polymeric pigment | (mg/L) | 10.9 ± 0.63 g | 18.4 ± 0.56 e | 19.6 ± 0.29 e | 36.2 ± 1.96 a | 15.5 ± 0.18 f | 20.1 ± 1.15 de | 22.1 ± 0.35 cd | 31.9 ± 0.48 b | 24.5 ± 0.1 c | <0.0001 |
| Tannin concentration and composition | |||||||||||
| Tannin | (mg/L) | 232 ± 20.01 e | 539 ± 27.95 b | 513 ± 2.29B c | 82 ± 73.22 a | 369 ± 29.37 d | 545 ± 44.99 b | 548 ± 12.53 b | 742 ± 73.40 a | 723 ± 7.29 a | <0.0001 |
| Molecular mass (subunit) § | (g/mol) | 1144 ± 32 f | 1372 ± 32 d | 1351 ± 19 d | 2026 ± 65 a | 1183 ± 5 ef | 1333 ± 44 de | 1441 ± 14 cd | 1770 ± 15 b | 1541 ± 22 c | <0.0001 |
| Molecular mass (50% GPC) § | (g/mol) | 1444 ± 50 abc | 1457 ± 25 abc | 1430 ± 17 bc | 1537 ± 71 a | 1473 ± 25 abc | 1423 ± 35 c | 1453 ± 25 abc | 1477 ± 15 abc | 1531 ± 9 ab | <0.01 |
| mDP †† | no units | 3.79 ± 0.12 f | 4.52 ± 0.11 d | 4.43 ± 0.07 d | 6.64 ± 0.20 a | 3.90 ± 0.03 ef | 4.38 ± 0.14 de | 4.72 ± 0.04 cd | 5.81 ± 0.06 b | 5.05 ± 0.07 c | <0.0001 |
| Mass conversion‡‡ | (%) | 13.68 ± 0.64 d | 26.01 ± 0.60 a | 27.11 ± 0.97 a | 20.48 ± 1.40 bc | 17.57 ± 0.67 cd | 24.35 ± 0.87 ab | 24.69 ± 0.10 a | 17.92 ± 0.77 c | 17.50 ± 0.57 cd | <0.0001 |
| Galloylation §§ | (%) | 5.80 ± 0.90 ab | 5.65 ± 0.34 ab | 5.88 ± 0.08 ab | 4.88 ± 0.13 ab | 6.94 ± 0.67 a | 6.11 ± 0.20 ab | 5.49 ± 0.07 ab | 4.51 ± 0,25 b | 6.25 ± 0.34 ab | <0.05 |
| Epigallocatechin (ext.) §§ | (mol %) | 18.34 ± 1.69 d | 30.74 ± 0.93 c | 34.22 ± 0.49 bc | 44.88 ± 2.0 a | 17.00 ± 1.23 d | 30.47 ± 2.46 c | 40.96 ± 1.29 ab | 46.10 ± 1.49 a | 33.08 ± 1.69 c | <0.0001 |
| Catechin (ext.) §§ | (mol %) | 4.16 ± 0.23 a | 3.43 ± 0.09 abc | 3.48 ± 0.15 abc | 2.12 ± 0.12 e | 3.55 ± 0.18 abc | 3.59 ± 0.17 ab | 3.14 ± 0.01 bcd | 2.42 ± 0.23 de | 2.78 ± 0.12 cde | <0.0001 |
| Epicatechin (ext.) §§ | (mol %) | 47.31 ± 1.03 a | 39.23 ± 0.77 b | 35.17 ± 0.90 bc | 34.06 ± 1.70 bc | 49.23 ± 1.30 a | 38.69 ± 1.76 b | 30.80 ± 1.05 c | 30.91 ± 1.94 c | 39.55 ± 1.44 b | <0.0001 |
| Epicatechin-gallate (ext.) §§ | (mol %) | 3.75 ± 0.64 | 4.43 ± 0.29 | 4.57 ± 0.08 | 3.86 ± 0.02 | 4.57 ± 0.28 | 4.36 ± 0.15 | 3.92 ± 0.07 | 3.37 ± 0.25 | 4.78 ± 0.26 | ns |
| Catechin (ter.) §§ | (mol %) | 16.48 ± 0.24 a | 13.07 ± 0.25 b | 12.92 ± 0.33 b | 8.63 ± 0.49 c | 16.74 ± 0.29 a | 13.19 ± 0.39 b | 12.13 ± 0.17 b | 10.05 ± 0.20 c | 11.80 ± 0.06 b | <0.0001 |
| Epicatechin (ter.) §§ | (mol %) | 7.90 ± 0.61 ab | 7.89 ± 0.28 ab | 8.33 ± 0.14 a | 5.43 ± 0.24 c | 6.55 ± 0.03 bc | 7.95 ± 0.39 ab | 7.47 ± 0.03 ab | 6.02 ± 0.04 c | 6.54 ± 0.21 ab | <0.0001 |
| Epicatechin-gallate (ter.) §§ | (mol %) | 2.05 ± 0.32 ab | 1.21 ± 0.05 bc | 1.31 ± 0.04 bc | 1.02 ± 0.12 c | 2.37 ± 0.43 a | 1.75 ± 0.11 abc | 1.58 ± 0.01 abc | 1.14 ± 0.01 bc | 1.47 ± 0.11 abc | <0.001 |
† Data presented show mean values ± standard error; treatments were compared using one-way ANOVA where p < 0.05, n = 3, and differences between treatments were determined by a post-hoc Tukey’s test with significance indicated by different letters, ns = not significant; ‡ H-1, H-2, H-3 = harvest-1, harvest-2 and harvest-3; DA-1, DA-2 = direct addition treatment 1 and direct addition treatment 2; RR-1, RR-2 = juice substitution treatment-1, juice substitution treatment 2; RO-1, RO-2 = saigneé treatment 1 and saigneé treatment 2; § = molecular mass determined by using subunit composition from phloroglucinolysis (subunit) or determined at 50% elution by gel permeation chromatography (50% GPC); †† = mean degree of polymerization; ‡‡ = mass conversion based on % recovery of proanthocyanidin by phloroglucinolysis as a proportion of tannin concentration by methyl cellulose precipitation; §§ = molar proportion of subunits released by phloroglucinolysis: galloylation, total epicatechin-gallate including both extension and terminal subunits, ter. = terminal unit; ext. = extension unit.