Step 2: Add cold water to the pressure cooker, put in the old ginger slices, then put in the blanched stick bones, put some pepper, and very importantly add a few drops of white vinegar.
PS: 1, with cold water stew soup, cold water to be sure to add enough, cold water can make the meat outer layer of protein will not immediately solidify, the inner and outer layer of protein can be fully dissolved into the soup, so that the soup tastes more fresh.
2, stewed bone broth, add a few drops of white vinegar, because vinegar can make the bones of calcium, phosphorus dissolved into the soup, and do not add salt too early, because salt can make the meat containing water quickly run out, will accelerate the protein coagulation, affecting the flavor of the soup.