Effects of Moisture Content, Loading Rate, and Grain Orientation on Fracture Resistance of Paddy (Oryza Sativa L.) Grain

Research Article
Effects of Moisture Content, Loading Rate, and Grain Orientation on Fracture Resistance of Paddy (Oryza Sativa L.) Grain

H. Zareiforoush, M.H. Komarizadeh, M.R. Alizadeh, H. Tavakoli and M. Masoumi

International Journal of Food Properties, 2012, 15(1), 89-98. DOI: 10.1080/10942911003754643

Abstract

In order to predict the extent of mechanical damage of rice kernels during de-husking, milling, and other subsequent storage projects, information on such engineering properties of paddy grains as force and deformation curve must be provided. In this research, fracture resistance of paddy grain was determined in terms of grain rupture force and energy. The paddy grains were quasi-statically loaded in horizontal and vertical orientations at three moisture content levels of 8, 11, and 14% (w.b) and two loading rates of 5 and 10 mm min⁻¹. In the current study, 12 treatments were performed as randomized complete block design with 10 replications. Based on the results obtained, as the moisture content of the paddy grain increased from 8 to 14% (w.b), the force required for initiating grain rupture decreased from 167.70 to 88.33 N and 43.55 to 21.68 N, and the energy absorbed at grain rupture increased from 13.08 to 34.39 mJ and 10.38 to 26.98 mJ, for horizontal and vertical orientations, respectively. This showed that the grains are more flexible in horizontal orientation. Furthermore, both the rupture force and energy decreased as the loading rate increased from 5 to 10 mm min⁻¹.

ASCI-ID: 198-217

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