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Thermomechanical Transitions of Rice Kernels
Author(s) -
Sun Zhenhua,
Yang Wade,
Siebenmorgen Terry,
Stelwagen Annemieke,
Cnossen Auke
Publication year - 2002
Publication title -
cereal chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.558
H-Index - 100
eISSN - 1943-3638
pISSN - 0009-0352
DOI - 10.1094/cchem.2002.79.3.349
Subject(s) - differential scanning calorimetry , glass transition , chemistry , plasticizer , moisture , thermomechanical analysis , starch , melting temperature , transition temperature , thermal analysis , thermal , analytical chemistry (journal) , thermodynamics , materials science , food science , composite material , polymer , chromatography , organic chemistry , physics , superconductivity , quantum mechanics
Thermomechanical analysis (TMA) and differential scanning calorimetry (DSC) were used to investigate the thermal transitions of long‐grain rice kernels. Three distinct thermomechanical transitions were identified as rice kernels were heated from 0 to 200°C. The identified transitions were a low temperature transition with onset at ≈45°C, an intermediate temperature transition at ≈80°C, and a high temperature transition at ≈180°C. Low temperature transition with onset from ≈60°C at 5% moisture content (MC) to 30°C at 20% MC was identified as the glass transition of the rice kernels. Intermediate temperature transition from 60 to 100°C, depending on MC, may be caused by rapid evaporation of moisture in the rice kernels. High temperature transition was associated with melting of the crystalline structure of rice starch. The temperatures of all three transitions decreased as MC increased, confirming that moisture acted as a plasticizer in rice kernels.