K Kruger
TVWBB 1-Star Olympian
Assume for the moment that you've purchased a bone-in butt, and that all the conditions of processing the meat leading up to your purchase were exactly as they were supposed to be. Further assume that you handle the meat correctly, get it in to cook, and your meat reaches say, 175, before something happens (whatever), and your internal drops to 130. Would there likely be a bacterial issue? No. So long as the surface temp of the meat remained above 140, you're probably fine. [Important note: For the sake of this illustration I am discounting the possibility that you may have pushed external bacteria into the meat with your probe.]
You are correct that the bacteria were killed during the temp rise (trichina, formerly a major concern in pork, now very rare, is killed at 137). Here's where it gets tricky and where the 'danger zone' of 40-140 comes in to play: Same scenario as above, but this time assume that the surface temp of the meat was 135. Let's say the meat was in that condition for one or two hours, or you just can't be sure. This is potentially dangerous. Though bacteria were killed during the first stage of the cook, once the temp gets below 140 for a period of time a whole new door opens for new bacteria to colonize. The more time that elapses, the worse the potential. Though you can stoke your cooker and bring your temps up and kill the bacteria, they are no longer the problem. The toxins that they produced are the problem, and no matter how high a temp you can get out of your cooker, you can not destroy them.
You are correct that the bacteria were killed during the temp rise (trichina, formerly a major concern in pork, now very rare, is killed at 137). Here's where it gets tricky and where the 'danger zone' of 40-140 comes in to play: Same scenario as above, but this time assume that the surface temp of the meat was 135. Let's say the meat was in that condition for one or two hours, or you just can't be sure. This is potentially dangerous. Though bacteria were killed during the first stage of the cook, once the temp gets below 140 for a period of time a whole new door opens for new bacteria to colonize. The more time that elapses, the worse the potential. Though you can stoke your cooker and bring your temps up and kill the bacteria, they are no longer the problem. The toxins that they produced are the problem, and no matter how high a temp you can get out of your cooker, you can not destroy them.