Table 6.
Central composite design with two coded (x3 and x4) and decoded (X3 and X4) variables and the response function (W) for the conversion of conjugated isoflavones into their corresponding aglycones.
| Assays | Block | Coded Variables | Decoded Variables | Response Function (W) | ||
|---|---|---|---|---|---|---|
| x 3 | x 4 | T (°C) (X3) | pH (X4) | % Aglycones * | ||
| 1 | 1 | −1 | −1 | 20.0 | 4.00 | 47.5 |
| 2 | 1 | +1 | −1 | 50.0 | 4.00 | 44.6 |
| 3 | 1 | −1 | +1 | 20.0 | 7.00 | 68.6 |
| 4 | 1 | +1 | +1 | 50.0 | 7.00 | 84.0 |
| 5 (c) | 1 | 0 | 0 | 35.0 | 5.50 | 88.6 |
| 6 (c) | 1 | 0 | 0 | 35.0 | 5.50 | 79.0 |
| 7 (c) | 1 | 0 | 0 | 35.0 | 5.50 | 88.6 |
| 8 | 2 | 0 | −1.41 | 35.0 | 3.39 | 11.6 |
| 9 | 2 | 0 | +1.41 | 35.0 | 7.61 | 98.7 |
| 10 | 2 | −1.41 | 0 | 13.9 | 5.50 | 48.6 |
| 11 | 2 | +1.41 | 0 | 56.2 | 5.50 | 47.1 |
| 12 (c) | 2 | 0 | 0 | 35.0 | 5.50 | 85.0 |
| 13 (c) | 2 | 0 | 0 | 35.0 | 5.50 | 88.3 |
* % aglycone isoflavones relative to total isoflavones extracted, determined by ultra-high-performance liquid chromatography (UHPLC). High-aglycone defatted soybean cotyledon flours were produced by treatment with β-glucosidase from germinated soybean epicotyls. “c” is central point.