Table 2.
Physicochemical properties of rice starch.
| Physicochemical properties | Early rice | Late rice | |||||
|---|---|---|---|---|---|---|---|
| Treatments | CK | SBR | SR | CK | SBR | SR | |
| Thermal properties | To (°C) | 67.1a | 66.2b | 67.5a | 62.6b | 66.2a | 66.6a |
| Tp (°C) | 72.3a | 71.6a | 72.8a | 68.8b | 71.0a | 72.9a | |
| Tc (°C) | 76.6b | 75.5b | 77.6a | 74.0b | 75.9b | 77.2a | |
| ΔHgel (J/g) | 9.8b | 10.3a | 10.5a | 10.4b | 10.7b | 11.1a | |
| R | 9.5b | 9.3b | 10.1a | 11.4a | 9.7c | 10.6b | |
| PHI | 1.9a | 2.0a | 2.0a | 1.7a | 2.2a | 1.8a | |
| Pasting properties | PV(cP) | 4911b | 4939b | 5311a | 3543b | 3432c | 4055a |
| TV(cP) | 2212a | 2034b | 2213a | 2363a | 2352a | 2487a | |
| FV(cP) | 3053b | 3050b | 3260a | 4082a | 4140a | 4208a | |
| BD(cP) | 2699c | 2905b | 3098a | 1181b | 1080b | 1568a | |
| SB(cP) | −1858a | −1889a | −2052b | 539a | 708a | 153b | |
| PaT(°C) | 84.62a | 85.17a | 84.63a | 74.68a | 74.47a | 73.93a | |
| Textural properties | Hardness (g) | 2007.4a | 1950.5b | 1837.7c | 2771.6a | 2731.4a | 2342.2b |
| Stickiness (g) | −399.4b | −427.7b | −354.9a | −257.3a | −363.6b | −260.4a | |
| Springiness | 0.54a | 0.55a | 0.53a | 0.68a | 0.70a | 0.71a | |
| Cohesiveness | 0.24a | 0.24a | 0.20b | 0.37b | 0.41a | 0.31c | |
| Chewiness(g) | 475.6a | 461.5a | 444.2b | 911.2a | 1062.4a | 733.6b | |
Different lowercase indicates significant differences in different values at p < 0.05 in the same column and the same rice season.
To, onset temperature; Tp, the peak of gelatinization temperature; Tc, conclusion temperature; ΔHgel, gelatinization enthalpy.
PV, peak viscosity; TV, trough viscosity; BD, breakdown; FV, final viscosity; SB, setback; PaT, pasting temperature.
CK, straw removed with chemical fertilizers application; SBR, straw burning returning; SR, straw returning in situ.