A technological production line for candied lemon slices was developed to maximize the preservation of vitamin C. A new drying method was introduced: the thermal agent is filtered through a wet layer of lemon slices at a temperature of 70 °C. After a certain period, when the upper layers have reached their final moisture content, a thermal agent at a temperature of 18 °C is supplied. The lower layers of the material are dried using the energy accumulated by the upper layers. This process reduces energy consumption by 4659 kJ/kg of moisture.