Because if you stew, soybean soaked in water. If the stew is longer, red beans soaked in water heating is also very easy to be stewed.

The general practice of soybeans before stewing pig's feet is to soak in cold water for about half an hour.

After absorbing the cold water, it will be swollen and full, and then put into the pot with the pig's feet and stew will be directly, well, rotten and then the taste will be a little better.