Table 3.
Probable alcohol (%v/v) in grape berries of Touriga Nacional and Touriga Franca grape variety during different time of sampling until maturation.
| Variety/Sampling Time | Control | Kaolin 5% | Potassium Silicate (0.1%) | Potassium Silicate (0.05%) |
|---|---|---|---|---|
| Touriga National | ||||
| 26/07 | 5.6 ± 0.1 aA | 5.4 ± 0.2 aA | 5.4 ± 0.1 aA | 5.4 ± 0.2 aA |
| 02/08 | 8.4 ± 0.1 bA | 7.8 ± 0.8 bA | 8.6 ± 0.6 bA | 8.4 ± 1.6 abA |
| 09/08 | 12.8 ± 1.5 cdA | 12.2 ± 1.8 dA | 11.0 ± 0.2 cA | 11.5 ± 1.7 bcA |
| 17/08 | 9.6 ± 0.2 bcA | 11.2 ± 0.1 cA | 10.6 ± 0.1 cA | 11.3 ± 0.7 bcA |
| 23/08 | 10.6 ± 1.4 bcdA | 11.7 ± 0.1 cA | 11.6 ± 0.1 cdA | 11.5 ± 0.4 bcA |
| 07/09 | 12.8 ± 0.9 cdA | 12.8 ± 0.1 dA | 13.5 ± 0.1 eA | 13.4 ± 0.6 cA |
| 20/09 | 13.4 ± 0.0 dA | 13.0 ± 0.1 dA | 12.7 ± 0.5 deA | 12.9 ± 0.0 cA |
| Touriga Franca | ||||
| 26/07 | 5.6 ± 0.1 aA | 5.2 ± 0.9 aA | 5.4 ± 0.7 aA | 5.5 ± 0.6 aA |
| 02/08 | 9.3 ± 0.3 bA | 6.7 ± 0.3 abA | 7.4 ± 2.5 abA | 6.5 ± 2.8 abA |
| 09/08 | 9.1 ± 0.1 bA | 8.3 ± 0.8 bA | 8.8 ± 2.3 bA | 9.0 ± 2.6 bA |
| 17/08 | 10.2 ± 0.6 cA | 10.6 ± 1.2 bA | 10.4 ± 0.0 cA | 11.3 ± 0.0 cA |
| 23/08 | 11.0 ± 1.1 cA | 11.0 ± 0.7 bcA | 12.2 ± 0.8 cdA | 11.0 ± 0.6 cA |
| 07/09 | 11.9 ± 0.6 dA | 12.4 ± 0.8 cA | 13.0 ± 0.1 dA | 13.4 ± 0.1 dA |
| 20/09 | 12.2 ± 0.1 dA | 12.5 ± 0.6 cA | 13.0 ± 0.8 dA | 13.2 ± 0.3 dA |
Means (average ± standard deviation) within a column followed by different lower case letters are significantly different (p < 0.05). Values with the same capital letter on the same line for each grape variety and sampling data are not significantly different from each other at p < 0.05.