Table 1. Central composite design for optimization of reducing residual patulin content and maintaining polyphenolic content in apple juice
| Exp. No.1) | Independent variables | Response variables |
| Storage temp.(X1, °C) | Irradiation dose(X2, kGy) | Storage period(X3, day) | Residual patulin content(ppb) | Polyphenolics content(mg/g) |
| 1 | −10 (−1) | 0.5 (−1) | 5 (−1) | 259.972) | 10.41 |
| 2 | 10 (1) | 0.5 (−1) | 5 (−1) | 271.19 | 11.69 |
| 3 | −10 (−1) | 0.5 (−1) | 15 (1) | 190.45 | 10.32 |
| 4 | 10 (1) | 0.5 (−1) | 15 (1) | 236.01 | 10.38 |
| 5 | −10 (−1) | 1.5 (1) | 5 (−1) | 172.79 | 11.70 |
| 6 | 10 (1) | 1.5 (1) | 5 (−1) | 218.38 | 11.26 |
| 7 | −10 (−1) | 1.5 (1) | 15 (1) | 143.52 | 11.23 |
| 8 | 10 (1) | 1.5 (1) | 15 (1) | 113.78 | 11.08 |
| 9 | 0 (0) | 1.0 (0) | 10 (0) | 100.12 | 11.00 |
| 10 | 0 (0) | 1.0 (0) | 10 (0) | 115.75 | 11.03 |
| 11 | 0 (0) | 0.0 (−2) | 10 (0) | 673.26 | 10.41 |
| 12 | 0 (0) | 2.0 (2) | 10 (0) | 237.47 | 11.40 |
| 13 | 0 (0) | 1.0 (0) | 0 (−2) | 248.76 | 11.81 |
| 14 | 0 (0) | 1.0 (0) | 20 (2) | 156.94 | 10.17 |
| 15 | −20 (−2) | 1.0 (0) | 10 (0) | 121.23 | 11.31 |
| 16 | 20 (2) | 1.0 (0) | 10 (0) | 80.01 | 11.42 |
The number ofexperimental conditions by central composite design.
All values are mean±SD (n=3).