I heard that many canned food processing plants, such as canned eight-treasure porridge, are dirty and full of rats?

You're just hearsay. That's not true. I didn't dare to say before, but now canned food materials (materials that come into direct contact with food) must declare QS permission, and there is a special agency responsible for management and supervision. Canned eight-treasure porridge manufacturers also implement the food QS production license management system. There won't be rats everywhere. Unless you buy products from underground processing plants.