I've made several batches of bacon and smoking it on my Masterbuild electric smoker. I usually have a 10 pound pork belly that I cut in half before curing, then smoke it at 200 degrees until it reaches an internal temp of 150 degrees. In the last couple of batches, they're developed a thin rubbery rind on the fat cap and I'm not sure why that's happening. Any ideas on what might cause that? I have 20 pounds curing now that I plan to smoke and slice in a couple of days. Any help would be appreciated.