Milk stains are water-soluble stains. The newly stained milk stains can be soaked in cold water (18 degrees) for 3-60 minutes, and then washed repeatedly with raw soap to remove them. When soaked in clear water, a small amount of salt or ammonia water can improve the decontamination effect. Old milk stains are difficult to remove. Consider the following methods: (1) Grind carrots or white radishes, mix them with salt, smear them on the stains, rub them repeatedly with your hands, and then rinse them with clear water. Because protein in milk meets amylase in radish, it will decompose, thus removing stains. (2) It is also effective to scrub milk stains with ginger. (3) Wash with detergent first, then with dilute ammonia water, and finally rinse with clear water. Milk stains should not be washed with hot water. In case of high temperature, the protein in such stains will be firmly combined with the fiber, which is more difficult to remove.