Investigation of moisture changing and breakage percent of paddy seeds by using of microwave dryer

Document Type : Research Article


1 M.Sc. student, Bio Systems Engineering, Department of Bio Systems Engineering, Sari University of Agricultural Sciences and Natural Resources, Sari, Iran

2 Assistant Professor, Bio Systems Engineering, Department of Bio Systems Engineering, Sari University of Agricultural Sciences and Natural Resources, Sari, Iran

3 Assistant Professor, Bio Systems Engineering, Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran


Drying process is one of the most sensitive steps during paddy conversion operations.  Using the accurate, scientific and technical principals in paddy drying process causes increasing the paddy conversion efficiency and longer storage time. Therefore in this study, influence of different conditions of a laboratory microwave oven on the drying rate and the grain breakage have been investigated in terms of the measured moisture decrement, percent of broken paddies, microwave power, power and relaxation times. Two conventional and well known varieties in Mazandran province “Nemat” and “Tarom Hashemi” have been investigated in the current research. The obtained results indicated that the percent of broken paddies significantly increases with increasing the oven powers ranging from 90 to 450 watt and simultaneously the moisture ratio reduced. According to the results obtained in the present study, powers more than 450 watt causes burning the paddy are as a result doesn’t recommended for the laboratory or industrial applications. The obtained results indicated that the wave period of 30 second, tempering period of 60 second and 270 watt power are the suitable condition for drying the investigated paddies via microwave rays. In this condition, the average broken seeds was equal to 29.37%.


Main Subjects

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