The drying of fresh fruits, vegetables, agricultural products, herbs and meat has always been a very energy consuming process. The conventional methods (sun drying, electric and gas-fired dryers) require high temperatures which can affect the nutrient content of the dried material.
Heat pump dehydrator can provide low temperature drying to avoid the loss of nutrient contents and to achieve good quality dried products. The heat pump can produce both latent and sensible heat with a very low energy consumption, thus it is an environmentally friendly and economical drying technology.
Moreover, the heat pump system can recycle the water through the evaporator and condenser cycles to reuse its latent heat of vaporization for drying. This reduces the energy consumption and enables higher energy utilization efficiency compared to traditional heating sources.
Some research on heat pump drying of food materials has shown that HPD can improve the quality characteristics of fruit and vegetable products, such as microbial safety, color retention, vitamin C preservation, volatile compound and aroma retention, and texture. Chua et al. [29] reported that two-stage HPD with pre-selected cyclic temperature schedule can enhance the quality of various dried agricultural products, such as guava slices and sapota pulp. They found that the use of reduced air temperatures at onset and increased temperature as drying progressed in the HPD produced dried guava with significantly improved color, astringency and ascorbic acid retention.
The AIO-DF food dehydrator uses heat pump technology to precisely control the temperature and humidity of the drying chamber for a gentle drying process that maintains the nutrition, color, aroma, flavor, and texture of the foods. It also has a closed-loop air circulation design, so no energy is lost and the air is clean and hygienic.