Search results for "Hybrid Heating"

Comparing different processing methods in apple slice drying. Part 1. Performance of microwave, hot air and hybrid methods at constant temperatures

2019

The drying curves, energy efficiency and colour variations of sliced apples dried at various temperatures and using different techniques were evaluated, i.e. microwave (35, 55 and 65 °C), hot air (35, 55, 65 and 75 °C) and combination of both (65 °C). The microwave (MW) tests also included comparison between air recirculation and continuous inlet of fresh air. Each drying method was evaluated at a fixed temperature level by means of a control system based on infrared thermography. The time required to complete the drying process at 65 °C varied from about 44 min for MW with fresh air ventilation (double with air recirculation), to 122 min for hybrid heating and 238 min for hot air. Drying k…