Effects of Grain Moisture Content on the Mechanical and Physical Characteristics of Local Grains Darmanto Darmanto1*, Sandra Malin Sutan1, Andri Paska Ginting1
1Biosystems Engineering Department, Universitas Brawijaya, Jalan Veteran, Malang, East Java 65145, Indonesia
*Email: darmanto_sm[at]ub.ac.id
Abstract
The aim of this research is to obtain physical and mechanical properties of local East Java grains as well as the percentage of milled yield at various levels of moisture content, and to analyse the relationship between grain moisture content toward the physical, mechanical, and milling properties. An experimental method was conducted by conditioning the moisture content of the grain with the addition of water to then measured and tested its physical and mechanical properties and calculated the percentage of grain milled according to the variation of the moisture content. The results show that the geometrical properties (axial dimensions, surface area, volume, and roundness) of the grain of cempo rogo, mahameru, and glutinous rice mentok ponorogo increased with an increase in water content as well as the gravimetric properties and the bulk density. True density and porosity tended to fluctuate with increasing water content by 0,01-0,06 gram/𝑐-𝑚-2 and 0,8-0,9 %, respectively. The frictional properties tended to decrease with range 0.8-0.9, respectively. The stress tend to go down as the water content increases by 0.1-0.2 N, although the strain increased by 0,02-0,030 mm.
