Table 2.
Experiments performed and coded values of the variables using the Box-Behnken design
| Run | Independent variables |
| X1, Severity factor (Ro) | X2, Extraction temperature (°C) | X3, Ratio of water to material (mL/g) |
| 1 | 1 | 0 | –1 |
| 2 | 0 | 0 | 0 |
| 3 | 1 | 0 | 1 |
| 4 | –1 | 1 | 0 |
| 5 | 0 | 0 | 0 |
| 6 | 0 | –1 | –1 |
| 7 | –1 | 0 | –1 |
| 8 | 1 | –1 | 0 |
| 9 | –1 | 0 | 1 |
| 10 | 0 | –1 | 1 |
| 11 | 1 | 1 | 0 |
| 12 | 0 | 1 | 1 |
| 13 | 0 | 0 | 0 |
| 14 | 0 | 0 | 0 |
| 15 | –1 | –1 | 0 |
| 16 | 0 | 1 | –1 |
| 17 | 0 | 0 | 0 |