Drying of vegetables, fruits and other foods is an important part of the food processing industry. Now major food processing plants have achieved industrial production, the use of microwave dryer drying beef, chicken and other food has become the mainstream. Traditional drying methods have been gradually abandoned.

What are the main differences between microwave and conventional heating?
Microwave drying and traditional heating are two standard drying methods which have great influence on food processing industry. There are also significant differences in productivity and production quality between the two drying methods.
The mechanism of microwave food dryer is very different from that of traditional drying. In conventional drying, heat is transferred to the surface of the material by conduction, convection, or radiation, and to the interior of the material by heat conduction. Water initially flashes off the surface and the remaining water diffuses to the surface. This is usually a slow process in conventional drying and has a limited diffusion rate, requiring a higher external temperature to produce the desired temperature difference.
In conventional heating or surface heating, traditional drying methods use heat or sunlight. The treatment time is limited by the rate at which heat flows from the surface into the material body, which is determined by its specific heat, thermal conductivity, density, and viscosity. Surfaces are heated not only slowly but unevenly, with surfaces, edges and corners much hotter than the interior of the material. As a result, the quality of conventional heating materials is variable and often not as good as expected.
Microwaves are not a form of heat, but a form of energy, expressed as heat through interaction with materials. Microwaves initially excite the outer layers of molecules. As heat spreads inward from the outer layers, the inside of the material warms. Most of the water is evaporated before it leaves the material.
If the material is very wet and the internal pressure rises rapidly, the liquid will be discharged from the material due to the pressure difference. This creates a pumping effect that pushes the liquid, usually in the form of steam, to the surface. The result is very rapid drying without the need to overheat the atmosphere and may lead to surface hardening or other surface overheating.
Microwave food Dryer drying process, temperature gradient, heat transfer, steam pressure migration direction are consistent, so as to significantly improve the moisture migration conditions in the drying process, better than conventional drying. At the same time, due to the existence of pressure transfer dynamics, microwave dryer has the characteristics of drying from inside to outside. In other words, for wood and other materials as a whole, the inner layer of wood will dry first, thus overcoming the traditional drying of meat products in the outer layer of drying and forming a hard skin, to prevent internal water loss. From moving out.
Compared with these two drying methods, microwave sterilizer has obvious advantages.
1. Selective heating: microwave drying equipment allows uniform heating and uniform drying.
2. Energy saving and high efficiency: industrial microwave vacuum dryer directly acts on products; Therefore, there is no additional heat loss, the air in the oven and the corresponding container are not heated, so the thermal efficiency is extremely high, the production environment is significantly improved, saving electricity up to 30% compared to far infrared heating.
3. Short time, high efficiency: microwave penetrates from all directions, both inside and outside repair, so that the spice is heated evenly in a short time, significantly shortening the drying time.
4. Easy to control, advanced technology: compared with the traditional method, microwave drying equipment ready-to-use; No thermal inertia, flexible, easy to operate.
5. Long service life: microwave drying using food grade stainless steel and international famous brand motor and parts, reliable, to ensure the production of health standards.

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