First, use a little salt and vinegar to remove the mucus in the pig intestine, then turn it over with clear water for several times to remove dirt, then put the large intestine into a basin, add two teaspoons of vegetable oil, knead it by hand for about 10 minute, and finally rinse it with clear water. You can also marinate pork intestines with cola for half an hour, and then rub them with rice washing water.