With the development of production technology, more and more drying equipments appear, artificially controllable heat source and mechanical ventilation and dehumidification methods gradually replace the ancient method, and the effect is becoming more and more prominent.
Advantages of vacuum drying:
When drying under low pressure, the oxygen content is low, which can prevent the oxidative deterioration of the material to be dried, and can dry flammable and explosive dangerous goods; it can vaporize the moisture in the material at low temperature, and it is easy to dry heat-sensitive materials; it can recover the moisture in the material to be dried. Valuable and useful ingredients; can prevent the discharge of toxic and harmful substances in the dried materials, and can become an environmentally friendly "green" drying. Therefore, the application of vacuum drying equipment is becoming more and more extensive.
Disadvantages of vacuum drying:
A vacuum system capable of pumping water vapor is required, which leads to high equipment investment costs and high operating costs; low equipment production efficiency and small output. To overcome these shortcomings, many scientific and technological workers have made many efforts. At the same time, due to the many advantages of vacuum drying, some products have to use vacuum drying equipment.
Therefore, the development of vacuum drying equipment will be very promising.
In addition, vacuum drying has a series of advantages such as low drying temperature and relative lack of oxygen in the drying room, which can avoid fat oxidation and pigment browning. It is suitable for drying heat-sensitive food materials. In addition, the equipment cost and drying cost are relatively low. Drying plays an important role in food drying.
Vacuum microwave drying absorbs the advantages of both microwave heating and vacuum drying, and is a promising drying technology. Therefore, it is recommended that my country speed up the research and development of vacuum microwave drying devices.