Experimental study of multipurpose heat pump dryer for honey and pollen drying

Abstract

The study was performed for experiment of a multipurpose heat pump dryer for bee honey and pollen drying with capacity of 50 kg honey/batch and 20 kg pollen/batch. The average results of 10 drying batches shown that the drying time in accordance with the initial moisture content of the material, varied from 35 to 55 minutes for honey drying and 3h20 to 3h50 minutes for pollen drying to reach the required moisture content. Drying rates were of 6,6 %/h for honey and 6,03%/h for pollen, respectively. The required drying time versus initial moisture content of honey and pollen were determined.

The specific energy consumption was 0,148 kWh/kg for bee honey drying and 0,664 kWh/kg for pollen drying. There was no HMF content, diastase content was 11,61 Gothe in honey; vitamin C content and microbial indicators in pollen fitted well with export standards.

The result in comparison with the vacuum drying method shown that the multipurpose heat pump dryer has got a higher drying rate and a lower specific energy consumption for drying process.