The Working Principle Of Rice Polishing

Rice polishing is mainly based on two mechanisms: mechanical friction and wet softening
1. Mechanical friction polishing
Polishing roller friction: The polishing machine is equipped with a high-speed rotating polishing roller (usually made of polyurethane, rubber, or diamond material) inside, and the rice particles rub against the polishing roller and rice particles in the polishing chamber to remove surface bran powder.
Airflow assistance: During the polishing process, the airflow generated by the fan carries away the shed bran powder, preventing it from reattaching to the rice grains and reducing the heat generated by friction.
2. Wet polishing (water mist polishing)
During the polishing process, a small amount of water mist or steam (usually controlled at 0.2% to 0.5% water addition) is sprayed onto the surface of the rice grains to soften the bran layer and make it easier to remove.
Excessive moisture can cause rice grains to absorb water and expand, increasing the rate of broken rice; Insufficient moisture results in poor polishing effect.