Effects of Moisture Content and Compaction Pressure on Bulk Density of Rye

Highlights Rye grain compaction was measured for three different moisture contents (8%, 12%, and 16% wet basis) at five different compaction pressures (7, 14, 34, and 55 kPa) Bulk densities were found to be statistically significantly dependent (p < 0.0001) on both the moisture content and applied pressure. Compacted bulk densities increased with increasing applied pressure for all moisture contents. Abstract. Bulk density of agricultural grains is needed to determine the quantity of grain in storage structures and to calculate grain pressures. The objective of this study was to investigate the effects of moisture content and applied pressure on bulk density of rye grain at moisture contents and pressures typical of those seen in storage structures. Rye compaction was measured for three moisture contents (8%, 12%, and 16% wet basis) at four compaction pressures (7, 14, 34, and 55 kPa) using a square box (based on the design used by Thompson and Ross, 1983). Data from the compaction tests were used to calculate the bulk densities for the three moisture contents and four compaction pressures. The bulk densities were found to be significantly dependent (p <0.0001) both on moisture contents and the pressure applied. Bulk densities varied with increasing moisture content as has been observed in similar studies for rye and other agricultural grains such as wheat and soybeans. These results provide guidance for estimating bulk density of rye in bins and other storage structures. Keywords: Grain compaction, Grain storage, Kernel rearrangement, Kernel elasticity.