Measurement of glass-rubber transition temperature of rice by thermal mechanical compression test (TMCT)

Abstract

TMCT (Thermal Mechanical Compression Test) was applied to measure the Tg-r (glass-rubber transition temperature) of rice flour and individual rice kernels at low moisture content (2.4-19.5% wet basis). As expected, Tg-r decreased with increasing moisture content. The T g-r temperatures measured by TMCT were comparable with those measured by DSC (Differential Scanning Calorimetry), TMA (Thermo-mechanical Analysis), and DMTA (Dynamic Mechanical Thermal Analysis) as reported in the literature. These results indicated that the TMCT technique could be applied to measure the glass-rubber transition of a single grain of rice or the rice in powder form. The sensitivity of the test was observed higher for the rice kernel than rice flour. TMCT technique has the advantage of usefulness and cost-effectiveness compared with the other techniques.