Modeling Moisture Movement in Rice

摘要: Rice is one of the leading food crops in world with total annual production being about 448 million metric tons on milled rice basis 2008/09 year (USDA, 2010). found marketplace different forms depending level its subsequent processing. Rough (or paddy rice) that obtained just after harvest. After removal outer husk hull), it becomes brown rice. Brown milling, where bran layer and embryo removed become whiter color called white favored form human consumption most countries. generally harvested at 18-24% moisture contents wet requires drying down to 12-14% for safe storage. At commercial scale, carried out by blowing heated air over grains causing them lose rapidly. In addition drying, movement inside kernels occurs when exposed dry or humid environments desorption adsorption moisture, respectively, during any preharvest post-harvest stages. During processes, surface kernel reaches equilibrium content surrounding environmental conditions very rapidly, however, center changes slowly, developing gradients within kernel. Higher magnitudes such are believed be major reasons fissures cracks rice, which result broken milling. Milled three-fourths more unbroken length head while rest 1994). Since full-length grain preferred has typically half market value than (Mossman, 1986; Thompson & Mutters, 2006). Therefore, reducing fissuring been an important goal research. last five decades, many researchers have pursued mathematical modeling process. Key objective model development was determine sample certain period. Development models also assisted understanding impact factors affecting process temperature speed optimizes time, without performing a large number experiments. Mathematical were used might affect fissuring. improve process, can help making decisions whether particular period time significant