I can't seem to find anywhere how to tie off natural hog casings sausage. I'm having issues getting the stuffed casing to stay stuffed when I leave the sausage unsmoked after stuffing them and put them in the freezer. I twist the links after stuffing the casing but as expected, after I cut the links apart the meat starts spilling out of the ends. I suspect the answer to this is simple but it's alluding me. Any ideas?