1, the fat (oil) on the skin is not scraped clean; 2, cooking time is not enough; There is too much water. If there is more water, the pigskin will not freeze. In this case, you should return to the pot and cook until the water comes up.

A, add enough water at a time, don't add water in the middle. Generally speaking, water can overflow the material. After high-pressure exhalation, turn to low heat and simmer slowly.

B, high-pressure cooking time is not fixed, generally about 2 kg of pigskin, it takes 45-60 minutes to cook with low fire.