Table 1.
Phenolic composition of the juice at the beginning (2 h) and at the end (72 h) of the process, and powder obtained by spray-drying (S-D) with the addition of arabic gum (AG).
| Phenolic Compounds | Concentration (mg/L) of Juice * | Concentration (μg/g of Powder) * | |
|---|---|---|---|
| Time | S-D + AG | ||
| 2 h | 72 h | ||
| Phenolic Acids | |||
| Caffeic acid | 0.06 ± 0.01 a | 0.43 ± 0.16 b | 0.8 ± 0.0 |
| Coumaric acid | 0.03 ± 0.00 | nd | 0.5 ± 0.1 |
| Ferulic acid | 1.7 ± 0.4 b | 0.14 ± 0.00 a | 29.4 ± 4.7 |
| Caftaric acid | 50.0 ± 6.6 b | 27.5 ± 1.7 a | 191 ± 5 |
| Coutaric acid | 15.9 ± 1.8 b | 9.4 ± 0.1 a | 27.6 ± 4.4 |
| Fertaric acid | 16.8 ± 3.1 a | 30.1 ± 3.3 b | 291 ± 73 |
| Gallic acid | 0.05 ± 0.00 a | 9.4 ± 2.1 b | 9.5 ± 0.3 |
| Flavonols | |||
| Quercetin | 0.07 ± 0.00 a | 0.29 ± 0.01 b | 1.3 ± 0.0 |
| Quercetin 3-O-glucoside | 0.13 ± 0.02 a | 19.8 ± 0.8 b | 11.8 ± 0.8 |
| Quercetin 3-O-glucuronide | 0.38 ± 0.07 a | 27.0 ± 1.2 b | 56.6 ± 3.1 |
| Rutin | 0.02 ± 0.00 a | 0.40 ± 0.03 b | 0.4 ± 0.0 |
| Isorhamnetin | 0.04 ± 0.00 | nd | 0.7 ± 0.0 |
| Kaempferol | 0.02 ± 0.00 | nd | 0.5 ± 0.0 |
| Myricetin | nd | 0.03 ± 0.00 b | nd |
| Flava-3-Ols | |||
| (−)-Epicatechin | 0.24 ± 0.02 a | 39.5 ± 1.6 b | 64 ± 12 |
| (+) Catechin | 6.3 ± 0.2 a | 38.4 ± 1.3 b | 327 ± 19 |
| Procyanidins | |||
| Procyanidin B1 | 0.82 ± 0.11 a | 23.9 ± 0.9 b | 19.0 ± 1.5 |
| Procyanidin B2 | 0.15 ± 0.00 a | 2.0 ± 0.1 b | 10.1 ± 1.0 |
| Stilbenes | |||
| Resveratrol | 0.01 ± 0.00 a | ± 0.00 b | 0.2 ± 0.0 |
* Data are presented as mean ± Standard Deviation (SD). Data are the mean of three replications. Significant differences (p < 0.05) are shown by a,b letters in the same line; nd, not detected.