Table 6. Significant individual phenolic compounds in the wine produced from Meili grapes based on density classes (mg L-1).
| Phenolic compounds | Wine sample | ||
|---|---|---|---|
| D3 α | D4 | D5 | |
| Nonflavonoid phenolics | |||
| Hydroxybenzoic acids | 85.32 (38.29%) | 104.40(37.08%) | 137.01(39.41%) |
| Gallic acid | 32.27 ±1.33(a) β | 36.25 ± 1.44(ab) | 38.15 ± 1.29(b) |
| Benzoic acid | 2.80 ± 0.49(a) | 4.39 ± 0.53(a) | 9.72 ± 1.04(b) |
| Vanillic acid | 29.24 ± 1.63(a) | 33.33 ± 2.24(a) | 58.55 ± 1.00(b) |
| Syringic acid | 5.03 ± 0.14(a) | 8.20 ± 1.11(b) | 8.03 ± 0.28(b) |
| p-Coumaric acid | 3.97 ± 0.55(a) | 8.04 ± 1.24(b) | 7.85 ± 0.87(b) |
| Salicylic acid | 12.02 ± 2.35(a) | 14.20 ± 1.65(a) | 14.72 ± 0.99(a) |
| Hydroxycinnamic acids | 28.45(12.77%) | 34.34(12.20%) | 46.59(13.40%) |
| Chlorogenic acid | nd γ | nd | nd |
| Caffeic acid | 7.16 ± 0.50(a) | 10.10 ± 1.53(ab) | 11.80 ± 0.42(b) |
| Ferulic acid | 21.29 ± 1.61(a) | 24.24 ± 1.12(a) | 34.79 ± 1.73(b) |
| Stilbenes | 0.88(0.40%) | 1.36(0.48%) | 1.49(0.43%) |
| trans-Resveratrol | 0.88 ± 0.10(a) | 1.36 ± 0.21(a) | 1.49 ± 0.26(a) |
| Benzopyrone | 8.99(4.03%) | 10.68(3.79%) | 13.14(3.78%) |
| Coumarin | 8.99 ± 0.75(a) | 10.68 ± 0.62(ab) | 13.14 ± 0.98(a) |
| Sum of individual nonflavonoid phenolics | 123.64(55.49%) | 150.78(53.54%) | 198.23(57.03%) |
| Flavonoids | |||
| Flavan-3-ols | 64.53(28.96%) | 88.82(31.54%) | 97.43(28.03%) |
| (+)-Catechin | 29.43 ± 1.71(a) | 46.28 ± 1.51(b) | 53.26 ± 1.53(c) |
| (-)-Epicatechin | 35.09 ± 1.65(a) | 42.55 ± 1.59(b) | 44.17 ± 1.01(b) |
| Flavonols | 34.64(15.55%) | 41.99(14.91%) | 51.95(14.94%) |
| Rutin | 19.12 ± 1.99(a) | 24.48 ± 1.60(a) | 31.53 ± 1.66(b) |
| Morin | nd | nd | nd |
| Quercetin | 9.71 ± 1.55(a) | 11.67 ± 1.22(ab) | 13.60 ± 0.30(b) |
| Kaempferol | 5.81 ± 0.76(a) | 5.84 ± 0.77(a) | 6.81 ± 0.34(a) |
| Hesperetin | nd | nd | nd |
| Sum of individual flavonoid phenolics | 99.17(44.51%) | 130.81(46.46%) | 149.37(42.97%) |
| Sum of individual phenolics | 222.81 ± 3.20(a) | 281.58 ± 6.25(b) | 347.60 ± 7.64(c) |
α D3, D4, and D5 indicate Meili wine produced from grapes at 1076 kg m-3, 1082 kg m-3, and 1089 kg m-3, respectively.
β Values are the mean ±standard deviation (n = 3). Within lines, significant differences according to the Fisher’s LSD test at the P≤0.05 level are indicated by different letters.
γ nd: not detected.