Energy consumption computing of cold plasma‐assisted drying of apple slices ( Yellow Delicious ) by numerical simulation

Abstract Energy consumption is a great challenge during fruit drying. New techniques such as cold plasma are used as pretreatment or the main treatment for food drying. In this work, apple drying with cold plasma was investigated with COMSOL simulation. Two treatments were designed: (a) traditional air drying at 60°C and 0.5 m/s airflow, and (b) cold plasma treatment at 100 W, and 60 Hz with laminar airflow at 60°C and 0.5 m/s. The samples were two apple slices with a 6 cm diameter and 0.3 cm thickness. Results show that plasma technology without airflow does not have an effective role in drying. But the combination of plasma and airflow drying reduced the drying time from the 9,600 s to 3,600 s. The plasma‐treated samples reached a constant moisture content faster than the air‐dried samples. The energy consumption of drying with plasma was 85‐fold lower than a traditional air‐drying method. The shrinkage of plasma‐treated samples was low and the total shrinkage was near the undried sample (0.008). Cold plasma probably can reduce the energy consumption, drying time, and final drying costs of fresh food drying. Practical application Drying with a combination of methods can reduce the processing time. In this work, the plasma technology was combined with air drying and the results show lower process time, lower shrinkage, and lower energy consumption. Plasma technology in combination with traditional air drying can reduce the drying time of food material from 9,600 s to 3,600s. The energy consumption of plasma drying was significantly lower than air drying. It can be concluded from these results that this drying method can be applied to study the drying of different types of food material.