Put the tripe in a basin, add salt and vinegar, and rub it repeatedly with both hands to remove the mucus from the tripe. Then wash off the mucus with water, put your hand into the tripe, grab the other end of the tripe with your hands, turn it over, still add salt and vinegar and rub it to wash off the mucus; then put the tripe into a pot of boiling water and scrape it , wait until the inner wall of the tripe is smooth, then turn the tripe over and put it into a pot of cold water. While heating, turn it over with a spoon. When the water boils, the fishy smell of the tripe can be removed, and then the tripe is still in the pot. Soak in cold water.