Microwaves are electromagnetic waves with frequencies ranging from 300MHz to 300GMHz, and their direction and magnitude undergo periodic changes over time. The process of microwave heating involves the direct interaction between microwaves and materials, converting ultra-high frequency electromagnetic waves into thermal energy. Water is a substance that strongly absorbs microwaves, and the water molecules in the material are polar molecules. Under the action of microwaves, their polarity orientation changes with the external electromagnetic field, causing rapid friction and collision of molecules, resulting in a series of processes such as heating and puffing of the material to achieve the purpose of microwave heating.

The non thermal factors exhibited by electromagnetic fields in the sterilization process have become the dominant factor in bacterial death, breaking the conventional pattern of heating sterilization. The object of resistance for bacteria to survive has been changed to "electromagnetic force". The sterilization mechanism of pulsed electromagnetic fields is mainly manifested in the following two aspects: electric field effect and ionization effect, commonly known as "non biological effects".

Equipment features:

1. Short time and fast speed: Conventional thermal sterilization transfers heat from the surface of food to the interior through methods such as heat conduction, convection, or radiation. It often takes a long time for the interior to reach the sterilization temperature. Microwaves utilize their transmission effect to uniformly and rapidly heat up and kill bacteria inside and outside the object through the combined effect of thermal and non thermal effects. The processing time is greatly reduced, and under high power density intensity, satisfactory results can be achieved in just a few seconds to tens of seconds.
2. Low temperature sterilization and preservation of drug ingredients: The rapid heating effect of microwave heating and non thermal biochemical effects enhance the sterilization function. Compared to conventional thermal sterilization, it can achieve insecticidal and bactericidal effects at relatively low temperatures and in a shorter period of time. Generally, the sterilization temperature is between 75-80 ℃ and the treatment time is 3-5 minutes. The unique microwave processing method can retain more effective ingredients, maintain the original color, aroma, taste, shape and other flavors. If conventional heat treatment is used to preserve 46-50% of vitamin C in vegetables, microwave treatment can reach 60-90%; Conventional heating of pig liver maintains vitamin A at 58%, while microwave heating reaches 84%.
3. Energy saving: Microwave electromagnetic conversion rate is high, generally above 70%, which is better than the electric heating efficiency of heating. In addition, microwaves directly convert magnetic thermal energy into food, and the microwave heater itself is not heated, so there is no additional thermal power consumption, which saves energy and electricity by 30-50% compared to electricity saving.