Re: Always wanted to knowI don't agree that meat stops taking on smoke at 140 or any other of the arbitrary temps I've read on the internet.
15-20 years ago when there were vastly fewer charcoal smokers (small offsets and bullets) and Q was mostly the provenance of larger all wood cookers, foil wrapping was originally used not a tenderizing aid, but a means to prevent over smoking, if smoke uptake stopped at a given temperature anyway, this would be unnecessary. Other methods to prevent over smoking were used as well, like cooking in paper grocery bags, cooking in cheese cloth etc.
Where I think the idea that smoke uptake stops at 140 came from, is that there is a temperature range that the formation of smokering stops.
Smokering is a chemical reaction between nitrites in the smoke (nitric oxide) and myoglobin in the meat. At a given temp, which varies with ph of the meat, the myoglobin denatures (protein molocules unwind) are are no longer able to make the conversion to the coveted pinkish purple color brisket cooks long to see when they slice a flat. This chemical reaction can end, depending on variables, anywhere between 104* and 160*.
It is important to note that although smokering is a valuable indicator that you've done things right during the cook, it really has no bearing on the actual smoke flavor.
Whether or not smoke uptake does stop is actually very easy to check, next time you cook a brisket or butt, use mellower woods for the duration of the cook, once the meat exceeds 140 or 160 or even during just the last hour of the cook, use cherry or mesquite or another distinctly flavored wood and see if you can taste it on the meat.
I've done this a couple of times, and you can absolutely taste the stronger smoke even after 160.