The factory of Le Trung Thien Co., Ltd. is equipped with several drying technologies, including hot air circulation drying, infrared drying, and heat-pump drying. The later is so-called low temperature drying.
With this technology, the exhausted air from the drying room is in heat exchange with a cooling loop (evaporator of an air-con) and then its temperature is lowered. The air become saturated with moisture (relative humidity reaches 100%) and the part of the moisture in the air is condensed and is removed as liquid (condensate). As the result, the air become drier when it is warmed up. This air is introduced again into the drying chamber where it can uptake more evaporate from the fruits.
With the matter of fact that the drier air is used, the drying temperature can be adjusted at lower value and the drying time is also shorter. These both factors help the product retain better nutritional and sensorial attributes. The mango, or generally all types of fruits, dried with the heat-pump drying machine will have better color (brighter) because it suffered less impact of heat.