What does the water case of hotel recruitment mean?

Hotel water case, water case refers to the personnel engaged in washing vegetables, opening chickens and opening fish, which is different from "white case" and "red case"

Red case: cutting meat

White shell: mixed with flour

Restaurant, hotel kitchen. In the north, it is divided into "red cases"-refers to the production of fish and eggs, and "white cases"-refers to the production of rice, noodles and snacks. In the south, it can be divided into "water case" and "dry case" or "hard case"