Table 4.
Full factorial design matrix of independent variables and their corresponding experimental and predicted yields of total phenolic content betacyanin, and betaxanthin for citric acid solution as solvent.
| Experimental Responses | Predicted Responses by RSM | Predicted Responses by ANN | ||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Sl. No. | Time (min) | Temperature (°C) | pH | TPC (mg of GA/g) | BC (mg/g) | BX (mg/g) | TPC (mg of GA/g) | BC (mg/g) | BX (mg/g) | TPC (mg of GA/g) | BC (mg/g) | BX (mg/g) |
| 1 | 5 | 40 | 5 | 5.26 | 2.44 | 2.42 | 5.51 | 2.88 | 3.13 | 5.31 | 2.39 | 2.41 |
| 2 | 10 | 40 | 5 | 5.30 | 2.34 | 2.33 | 5.32 | 2.67 | 2.99 | 5.34 | 2.43 | 2.34 |
| 3 | 15 | 40 | 5 | 5.30 | 2.28 | 2.29 | 5.08 | 2.56 | 2.91 | 5.25 | 2.35 | 2.28 |
| 4 | 20 | 40 | 5 | 4.82 | 2.17 | 2.23 | 4.82 | 2.55 | 2.86 | 4.76 | 2.20 | 2.23 |
| 5 | 25 | 40 | 5 | 4.83 | 2.15 | 2.20 | 4.53 | 2.64 | 2.83 | 4.74 | 2.11 | 2.20 |
| 6 | 30 | 40 | 5 | 4.66 | 2.13 | 2.17 | 4.22 | 2.83 | 2.83 | 4.74 | 2.11 | 2.17 |
| 7 | 5 | 40 | 4 | 5.17 | 1.18 | 1.70 | 5.68 | 1.71 | 2.4 | 5.23 | 1.08 | 1.64 |
| 8 | 10 | 40 | 4 | 4.86 | 0.78 | 1.56 | 5.52 | 1.61 | 2.27 | 4.84 | 0.80 | 1.45 |
| 9 | 15 | 40 | 4 | 4.53 | 0.67 | 1.32 | 5.33 | 1.61 | 2.16 | 4.48 | 0.79 | 1.36 |
| 10 | 20 | 40 | 4 | 4.67 | 0.62 | 1.27 | 5.12 | 1.71 | 2.08 | 4.69 | 0.71 | 1.30 |
| 11 | 25 | 40 | 4 | 4.65 | 0.61 | 1.23 | 4.87 | 1.89 | 2.02 | 4.66 | 0.59 | 1.26 |
| 12 | 30 | 40 | 4 | 4.43 | 0.56 | 1.22 | 4.62 | 2.18 | 1.99 | 4.40 | 0.58 | 1.22 |
| 13 | 5 | 40 | 3 | 5.20 | 0.44 | 1.10 | 4.94 | 0.33 | 1.22 | 5.11 | 0.48 | 1.07 |
| 14 | 10 | 40 | 3 | 5.05 | 0.33 | 1.01 | 4.83 | 0.33 | 1.05 | 4.93 | 0.31 | 1.05 |
| 15 | 15 | 40 | 3 | 4.85 | 0.25 | 0.87 | 4.68 | 0.43 | 0.92 | 4.88 | 0.26 | 0.97 |
| 16 | 20 | 40 | 3 | 5.33 | 0.24 | 0.96 | 4.51 | 0.63 | 0.80 | 5.21 | 0.23 | 0.94 |
| 17 | 25 | 40 | 3 | 4.54 | 2.32 | 0.85 | 4.31 | 0.93 | 0.72 | 4.65 | 2.34 | 0.90 |
| 18 | 30 | 40 | 3 | 4.47 | 2.23 | 0.84 | 4.07 | 1.32 | 0.66 | 4.35 | 2.02 | 0.88 |
| 19 | 5 | 30 | 3 | 5.23 | 0.68 | 1.23 | 5.22 | 1.21 | 1.79 | 5.14 | 0.69 | 1.13 |
| 20 | 10 | 30 | 3 | 4.26 | 0.44 | 0.78 | 5.14 | 1.13 | 1.65 | 4.42 | 0.50 | 0.82 |
| 21 | 15 | 30 | 3 | 4.62 | 0.33 | 0.85 | 5.03 | 1.14 | 1.53 | 4.43 | 0.39 | 0.77 |
| 22 | 20 | 30 | 3 | 3.90 | 0.26 | 0.66 | 4.89 | 1.26 | 1.44 | 4.08 | 0.37 | 0.68 |
| 23 | 25 | 30 | 3 | 3.86 | 0.25 | 0.65 | 4.72 | 1.47 | 1.38 | 4.06 | 0.26 | 0.65 |
| 24 | 30 | 30 | 3 | 3.80 | 1.00 | 0.64 | 4.52 | 1.77 | 1.34 | 3.85 | 0.89 | 0.63 |
| 25 | 5 | 30 | 4 | 7.08 | 2.77 | 2.49 | 6.73 | 2.84 | 2.95 | 6.99 | 2.70 | 2.48 |
| 26 | 10 | 30 | 4 | 7.12 | 2.65 | 2.46 | 6.61 | 2.65 | 2.84 | 7.09 | 2.56 | 2.42 |
| 27 | 15 | 30 | 4 | 7.14 | 2.53 | 2.38 | 6.46 | 2.56 | 2.75 | 7.03 | 2.41 | 2.40 |
| 28 | 20 | 30 | 4 | 7.26 | 2.58 | 2.44 | 6.28 | 2.57 | 2.69 | 7.15 | 2.46 | 2.42 |
| 29 | 25 | 30 | 4 | 7.17 | 2.51 | 2.38 | 6.07 | 2.67 | 2.66 | 7.30 | 2.46 | 2.40 |
| 30 | 30 | 30 | 4 | 7.12 | 2.47 | 2.38 | 5.83 | 2.88 | 2.65 | 7.23 | 2.47 | 2.34 |
| 31 | 5 | 30 | 5 | 8.13 | 3.35 | 2.81 | 7.34 | 4.24 | 3.63 | 8.13 | 3.20 | 2.75 |
| 32 | 10 | 30 | 5 | 8.28 | 3.33 | 2.80 | 7.18 | 3.95 | 3.54 | 8.17 | 3.20 | 2.79 |
| 33 | 15 | 30 | 5 | 8.20 | 3.30 | 2.77 | 6.98 | 3.76 | 3.48 | 7.96 | 3.22 | 2.80 |
| 34 | 20 | 30 | 5 | 5.23 | 3.28 | 2.78 | 6.76 | 3.66 | 3.45 | 5.35 | 3.36 | 2.78 |
| 35 | 25 | 30 | 5 | 5.08 | 3.20 | 2.73 | 6.51 | 3.66 | 3.44 | 5.11 | 3.36 | 2.75 |
| 36 | 30 | 30 | 5 | 5.03 | 3.07 | 2.73 | 6.23 | 3.76 | 3.46 | 4.97 | 3.18 | 2.72 |
| 37 | 5 | 20 | 3 | 5.42 | 1.34 | 1.71 | 4.56 | 1.29 | 2.01 | 5.56 | 1.42 | 1.63 |
| 38 | 10 | 20 | 3 | 5.21 | 1.07 | 1.55 | 4.52 | 1.12 | 1.89 | 5.37 | 1.28 | 1.57 |
| 39 | 15 | 20 | 3 | 4.52 | 0.90 | 1.43 | 4.44 | 1.05 | 1.79 | 4.56 | 1.05 | 1.51 |
| 40 | 20 | 20 | 3 | 4.28 | 0.91 | 1.48 | 4.34 | 1.07 | 1.72 | 4.26 | 0.88 | 1.47 |
| 41 | 25 | 20 | 3 | 4.22 | 0.88 | 1.42 | 4.21 | 1.23 | 1.68 | 4.30 | 0.84 | 1.43 |
| 42 | 30 | 20 | 3 | 4.22 | 0.85 | 1.41 | 4.05 | 1.42 | 1.66 | 4.16 | 0.80 | 1.41 |
| 43 | 5 | 20 | 4 | 5.81 | 2.42 | 2.40 | 6.86 | 3.15 | 3.15 | 5.72 | 2.39 | 2.43 |
| 44 | 10 | 20 | 4 | 6.12 | 2.31 | 2.32 | 6.77 | 2.88 | 3.06 | 6.01 | 2.37 | 2.37 |
| 45 | 15 | 20 | 4 | 6.60 | 2.28 | 2.33 | 6.66 | 2.75 | 2.99 | 6.44 | 2.34 | 2.32 |
| 46 | 20 | 20 | 4 | 6.28 | 2.23 | 2.27 | 6.51 | 2.63 | 2.95 | 6.22 | 2.30 | 2.28 |
| 47 | 25 | 20 | 4 | 6.18 | 2.22 | 2.23 | 6.34 | 2.65 | 2.94 | 6.13 | 2.24 | 2.29 |
| 48 | 30 | 20 | 4 | 6.19 | 2.21 | 2.21 | 6.13 | 2.76 | 2.95 | 6.19 | 2.21 | 2.30 |
| 49 | 5 | 20 | 5 | 7.26 | 3.31 | 2.75 | 8.25 | 4.80 | 3.8 | 7.23 | 3.37 | 2.74 |
| 50 | 10 | 20 | 5 | 8.13 | 3.37 | 2.80 | 8.12 | 4.42 | 3.74 | 7.99 | 3.34 | 2.73 |
| 51 | 15 | 20 | 5 | 8.28 | 3.36 | 2.77 | 7.96 | 4.14 | 3.7 | 8.42 | 3.32 | 2.74 |
| 52 | 20 | 20 | 5 | 8.05 | 3.36 | 2.79 | 7.78 | 3.96 | 3.69 | 8.16 | 3.32 | 2.78 |
| 53 | 25 | 20 | 5 | 7.95 | 3.29 | 2.77 | 7.56 | 3.88 | 3.75 | 7.73 | 3.37 | 2.78 |
| 54 | 30 | 20 | 5 | 7.67 | 3.29 | 2.74 | 7.32 | 3.89 | 3.75 | 7.59 | 3.38 | 2.75 |
RSM—Response Surface Methodology; ANN—Artificial Neural Network; TPC—Total Phenolic Compounds; BC—Betacyanin; BX—Betaxanthin; Responses are expressed as mg/g of beetroot powder for betacyanin (BC) and betaxanthin (BX), and as mg of gallic acid (GA)/g of beetroot powder for total phenolic compounds (TPC).