Originally Posted by e4c6
This might be a dumb question, but could someone describe the 90 degree test a little bit? Does this basically mean if you bend them, they should be able to form a right angle? If they're not tender enough, they won't be able to bend that far, correct?
Well, "tender enough" is a subjective term.
What I usually do is to watch for the meat to shrink back about 1/4" from the rib ends and then do the first bend test. If you're willing to do a little experimentation, eat the first rack (or part of it) that reaches 45 degrees and see how you like it. Then go incrementally from there until you get a rack that bends 90 degrees; it might take you more than 1 cook to do this but you'll get a better idea of judging the ribs that're cooked the way you like.