Microencapsulation of maltodextrin and gelatin using spray drying with double-condenser compression refrigeration systems

Abstract

In this study, a compressor air pressure of 2 bar was used to produce 20,91 ± 3,42 µm encapsulated maltodextrin. Next, energy consumption was measured to obtain specific energy consumption (SEC) by varying the flow, specific humidity, and drying air temperature, with and without a refrigeration system. The use of a refrigeration system enhances the dehumidification of drying air; however, when such a system is not used, energy consumption increases. The highest productivity exhibited by the spray dryer to produce microencapsulated maltodextrin and gelatin was 9,84 × 10−5 lps of liquid material. This productivity was realized for a drying airflow, drying air temperature, and specific humidity of 450 lpm, 120 °C, and 4,98 g/kg d.a., respectively. The lowest SEC was 9999,12 kJ/l for drying air flow, drying air temperature, and specific humidity of 150 lpm, 120 °C, and 4,95 g/kg d.a., respectively. The ratio of SEC (RSEC) is more important than SEC, where the minimum value of RSEC was 0,6 for a drying air flow, drying air temperature, and specific humidity of 300 lpm, 90 °C, and 4,58 g/kg d.a., respectively. However, the productivity under these conditions was 0,25 lph of liquid material, which is less than the maximum productivity (0,35 lph) discussed above.