quote:
Originally posted by Dale_MT:
Todd,
I reread your post regarding the plateau and I just realized the essence of what you are saying. (at least I think so). During the plateau period, the internal temp of the meat stays relatively constant and this lack of heat exchange in the meat causes the smoker temp to stay low as well? Is that what you are saying or am I reading too much into it? I ask this more for idle curiousity now. I know you certainly don't have to understand all of the mechanics of this to make it work. Again, though my airline training jumps in and makes me have to ask....
I understand the curiosity. I'm the same way, and as ridiculous as it sounds to my friends and other non-BBQ geeks, the plateau to me is really fascinating because there's a lot going on for something that most people would never think about. My engineering school days are long behind me, but if I recall correctly the laws of thermodynamics (entropy) apply here. (That's a sentence you don't see on many BBQ forums) The cooker will attempt to produce heat, but the butt can(will) absorb more heat than the cooker can produce, resulting in an apparent drop in temp, an actual drop also, but not one caused by a reduction of heat energy being applied, but rather by it's absorbtion and subsequent transformation into melted fat. Hence my reference to the rendering of fat as a heatsink. When the fat renders sufficently or entirely, the heat in the cooker will have no route of escape, and your temp will once again rise in both the cooker and the meat.
I've never checked, but I suspect that if you took frequent accurate readings of the meat and the ambient temp inside the cooker(CS), you'd find that the plateau ends when the two different temps match, however briefly. My guess is this would happen about 176-178*, then shazam, before you know it, you're at 190* and it's time to eat. The dynamics are slightly different for other types of cookers based on their heat production, but I think the process is basically the same.
And my earlier post was made without knowing your level of experience. A lot of new users report problems that are traced back to their inability to leave the door closed. I even admit to opening mine on occasion back in the day. Sounds like things are mostly straightened out though. Good deal.
For the record, I usually cook at least two butts at a time. I buy the twin packs from BJ's around 16-18#. They tend to cook in about 7.5-8.5 hours with cooker set at 225*, but I've had one butt go for 12 hours before. FWIW, I don't see any significant change in cook times between two and four butts either. I think the lack of mass just makes the temp fluctuations more drastic than the small heating element can compensate for in an 008. But if the element were bigger, the control on the thermostat would have to be much tighter and that would just drive up costs and most likely wouldn't save much time on an average cook. I think the 008 is a great example of the KISS principle. Low tech engineering that just works.
Also with a bigger element, you could just power through the plateau, and keeping it from doing it's job of breaking down the colagen in the meat. Sadly, this would mean no more tender meat. If you need proof, throw a butt in the kitchen oven at 400*. Set a meat therm for 195*. You're going to hit your temp pretty quick, and the meat is definitely "done" from a cooking standpoint, but I bet you don't want to eat it. Can you say chewey?
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