Hygienically Dehydrating the Onion Flakes Using Indirect Forced Flow Solar Dryer

Abstract

The performance and analysis of indirect forced flow solar dryer for dehydrating onion flakes are
presented. The dryer consists of a 320 W PV panel of 2 m² used as a solar heat absorber. The
experimentation was carried out in the period 10th March to 8th April 2020. During the test on 1st and 2nd
April 2020, the onion flakes moisture was lowered to 4% from 84.3 % in 12 h 48 minutes with average
irradiation 595 W/m2. The air velocity varied from 3.8 - 5.2 m/s. Total 3313 KJ of heat energy gave up by
hot air to onion flakes utilized for removal of 1140 g moisture. Initially, the moisture removal rate was
high; 1100 g moisture was removed in 8h, and rest moisture removal taken 5 h. The dried products were
completely hygienic and reach in color, aroma, and taste