عنوان مقاله [English]
Drying is one of the most common techniques for agricultural production processing which improves shelf life of the final product. Corn (Zea mayz) is a high nutritional value food and is an essential source of minerals and vitamins; thus it makes a substantial contribution to human nutrition. In this study the effects of hot air drying temperature (35, 50, 65 and 80°C), drum rotation speed (2, 6 and 10 rpm) and final moisture content of kernels (13 and 17 %) at constant air velocity (0.8 m/s) on drying time, percentage of broken kernels of corn, and percentage of crack of corn kernels were investigated. For this propose, the laboratory batch rotary dryer is designed. The results showed that increasing the temperature form 35 °C to 80°C, the percentage of broken grains and percentage of cracked grains increased and the drying time was decreased. Increasing the rotating cylinder rotation speed increased the drying time and the percentage of broken grains, but not significant effect in percentage of cracked grains.. The drying time, percentage of broken grains and percentage of cracked grains is lower in grain with 17 % db than the sample with 13 % db To obtain the desired quality parameter, the optimum drying for production of dried corn was determined as 65°C for 2 rpm and 17 % db.