بررسي عوامل موثر بر ايجاد ترك و خرده برنج در اثر خشك كردن شلتوك طي فرآيند تبديل

Investigation of the Effects of Drying Parameters on Rice Cracking and Breakage During Milling

Paddy, is one of the principal grains and before storage, and at the beginning of the milling process needs to be dried. A major part of grain losses occurs during drying. In order to examine the different factors affecting rice losses due to the drying process, this research was conducted. The experimental design used in this project was a split-split plot design with four factors of rice variety (Beenarn and Kazemi), drying air temperature (40, 50 and 60.C), final paddy moisture content (10, 12 and 14% w.b.), and depth of grain in the drying bin (0-10, 10-20 and 20-30 cm) at three replications. Effects of these factors on percentage of cracked (after drying) and broken rice kernels (after milling) were investigated. Results of the experiments showed that Kazemi variety was more sensitive to cracking than Beenam variety. Paddy moisture content of 14% was found to be appropriate for milling of both varieties. Statistical analysis of the data indicated that drying-air temperature of 40 C was suitable for drying of paddy. In this way, the cracked and broken grains were reduced after milling. Amount of cracking as well as rice breakage (after milling) in creased with increasing depth of paddy in the dryer bin.