After rice hulling process, the paddy becomes brown rice. After removing most of the cortex and part of the embryo of brown rice, we get rice.
White rice grain surface is covered with a small amount of chaff powder, which affects the rice appearance, storage and taste. So Rice Polishing Machine is necessary used to remove the chaff powder.
In order to improve the rice surface brightness, some illegal rice production manufacturer don’t only add water when polishing, but illegally add mineral oil. Due to mineral oil is harmful to our health so, adding mineral oil polished rice into a "poison rice".

After polishing process with rice polishing machine, rice becomes more white and more bright, taste is more delicious.
However, rice polishing machine also removes some nutrients of rice, rice bran is one of nutrients. Allegedly, squeezed in rice bran oil 5 L can be sold more than 100 RMB, which is more expensive than peanut oil.