Submitted to: International Journal of Food Engineering
Publication Type: Peer reviewed journal
Publication Acceptance Date: 1/26/2009
Publication Date: 4/1/2009
Citation: Jia, H., Li, D., Lan, Y., Bhandari, B., Chen, X., Mao, Z. 2009. Thermomechanical property of rice kernels studied by DMA. International Journal of Food Engineering. 5:1-13. Interpretive Summary: Rice is the most widely grown food grain crop and serves as the staple food for about half the world’s population. Much research has been reported on the physical, chemical, thermal, and some mechanical properties of rice, but thermomechanical properties of rice kernels remain to be investigated. A dynamic mechanical analyzer was used to test the thermomechanical properties of rice kernels. Results show that thermomechanical properties were not significantly affected by variety. The thermomechanical transition temperatures of the rice kernels were found to be inversely proportional to the moisture content. These findings can be used to evaluate rice quality in the rice industry.
Technical Abstract: The thermomechanical property of the rice kernels was investigated using a dynamic mechanical analyzer (DMA). The length change of rice kernel with a loaded constant force along the major axis direction was detected during temperature scanning. The thermomechanical transition occurred in rice kernel when heated. The transition temperatures were determined as 47°C, 50°C and 56°C for the medium-grain rice with the moisture contents of 18.1%, 16.0% and 12.5% (wet basis), respectively. Length change of rice kernel increased with increase of temperature and moisture content. Among four rice varieties investigated, the results showed that the thermomechanical property was not significantly affected by variety.