Bought a range raised pork belly. Cured this according to recipe. Cold smoked for 20 hours with a mix of apple and hickory. Hot smoked in my Camp Chef pellet grill oh high smoke (temp around 250F) until internal temp 130F. Sliced and ate same. Tasted sour. What do I do to keep this from happening in the future. {Note: I use Maple sugar, coarse Kosher salt and pink salt in the cure.} Thanks in advance for your help.