Table 1.
Mean1) values for the chemical compositions and pasting viscosity characteristics of yellow-fleshed potato flours
| Citric acid (%, s.b) | Starch citrate | MS2) (×10-2) | RS2) (%, d.b) | TS2) (%, d.b) | Tp 2) (°C) | Pasting viscosity (mPa·s) |
| Peak | Trough | Breakdown | Final | Setback |
| 40 | TWE-303) | 3.2±0.3a | 58.2±0.2a | 8 | -4) | - | - | - | - | - |
| 10 | - | 41.5±2.1e | 31.5±0.7e | 10.0±2.8e | 62.5±2.1e | 31.0±2.8e |
| 12 | - | 120.0±4.2d | 107.5±2.1d | 12.5±2.1d | 224.0±4.2d | 116.5±2.1d |
| TWE-503) | 2.7±0.1b | 58.0±1.0a | 8 | 88.1±0.9a | 708.0±5.7c | 535.0±4.2c | 173.0±9.9c | 750.5±3.5c | 215.5±7.8c |
| 10 | 77.6±0.2b | 1441.5±9.2b | 977.0±7.1b | 464.5±2.1b | 1503.0±2.8b | 526.0±9.9b |
| 12 | 76.5±0.5c | 2521.0±4.2a | 1410.5±6.4a | 1110.5±2.1a | 2440.0±4.2a | 1029.5±2.1a |
| | CVO5) | 2.8±0.1a | 29.3±0.2a | 12 | - | - | - | - | - | - |
| 10 | TWE-5P6) | 1.1±0.0c | 30.6±0.4b | 12 | 75.4±0.0a | 2338.0±2.8a | 1790.0±2.8a | 548.0±0.0a | 3218.0±4.2a | 1428.0±7.1a |
| | TWE-7P6) | 1.4±0.1b | 29.9±0.7ab | 12 | 75.5±0.1a | 635.0±1.4b | 302.5±3.5b | 350.5±2.1b | 613.0±7.1b | 310.5±3.5b |
Mean value of two measurement; values within a column sharing the same lowercase letter are not significantly different in a given concentration of citric acid (p<0.05).
MS; molar degree of substitution, RS; resistant starch content, TS; total solid content, Tp; Pasting temperature.
TWE-30 and TWE-50 treated at different screw speeds of 30 and 50 rpm, respectively, under identical REX conditions (150°C and 5 passes).
Not detected.
Treated in a convection oven at 150°C for 1 h.
TWE-5P and TWE-7P treated at different extruder passages of 5 and 7 passes, respectively, under identical REX conditions (150°C and 10 rpm).