2, cleaning. A coffee cup with good quality has a tight cup surface and fine pores, and it is not easy to attach coffee stains. After drinking coffee, you can keep the cup clean as long as you rinse it with clear water immediately. Coffee cups that have been used for a long time, or cannot be washed immediately after use, make coffee stains adhere to the surface of the cup. You can soak the cup in lemon juice to remove coffee stains. In the process of cleaning coffee cups, you must never use a hard brush to scrub, and you should also avoid using strong acid and strong alkali cleaners. The surface of coffee cups is scratched and damaged, which has an impact on the taste of coffee.