# Pork Shoulder took 36 hours to smoke - Why?



## mayor mcpork (Mar 13, 2013)

Over the weekend, I smoked a 6.5lb pork butt. It started with a good layer of yellow mustard and the Bone Dust rub. A day later I put the pork shoulder in my smoker at 10pm on Friday night. I went to sleep soon afterward but saw the temp on my remote thermometer. It cooked between 200 and 225 all night. At 6am it was up to an IT of 124 degrees. Seeming a little slow, I pushed the smoker temp into the 250-265 range. By 10am it had hit an IT 154 degrees and then dropped 5 degrees. It stalled for most of the afternoon. By my intended dinner time, it was still only at an IT of 161 degrees. I went to sleep at 11pm Saturday night with an IT of 169. On Sunday morning the IT had only gone up two degrees to 171! At 9:30am the IT was 176 but I pulled the butt, wrapped it, and stuck it in the cooler for two hours. At 11:30am the shoulder looked perfect, pulled apart perfectly, was moist and tender, and had great flavor. 

Why on earth would it take almost 36 hours to smoke a medium pork shoulder, and still not be able to hit a target IT of 200 degrees?

To set the record straight, I verified the IT of the shoulder at 176 degrees with a digital meat thermometer. Throughout the entire smoke, my Maverick thermometer was providing readings with both the meat probe and the thermometer on the grate, next to the shoulder. I test both Maverick probes and my other digital thermometer afterwards with the boiling water test. They all hit 212 as the water boiled.

What else would have led to such a long smoke? None of my other pork shoulders have gone past 13 hours when done at 225-250.


----------



## jp61 (Mar 13, 2013)

Did you have alarms set on your thermo, while sleeping? I've heard of loooong butt smokes, but never that long. I'm assuming you're using an electric or gas smoker?


----------



## jp61 (Mar 13, 2013)

I always take butts to 205°F IT and then into the cooler for a couple 2-3 hours usually. I have zero experience pulling butts around 186°F what yours might have reached in the cooler.  I'm guessing when I say, it wouldn't pull very easily around that IT. 

lol...... is this a test?


----------



## daveomak (Mar 13, 2013)

Was the exhaust wide open on the smoker ??  Was the butt frozen or partially frozen when you started ??  Were the intakes open on the smoker ??  Sounds as if there is a temperature reading that is incorrect.....  Not saying there is.... just sounds like there is.....   Dave

You say it was cooked perfectly and tasted great...  would you do anything different next time you smoked a butt ??


----------



## jarjarchef (Mar 13, 2013)

I am with Dave on this one.......sounds like you got a false reading somewhere......... I would on your next cook maybe change the placement of the cook chamber probe.......I have gotten crazy temps and then moved mine a few inches and then a very different reading.........

The other thing that raises a flag for me is the final cook temp reading you got......you should not of been able to pull it at 176....... When pork cooks you will go through different tenderness of the meat as it goes through the temp ranges........ 135-145 for a roast moist, tender and slice able...........145-185 tough but sliceable.........185-195 very tender and sliced carefully.........195+ pulled ............ When meat cooks it goes through a reaction to the heat where it will tighten up and get tough, but then when the connective tissue reaches a certain temp it will breakdown and get tender...........I would change the placement of the probe next time.........

Glad to hear you had a great meal...........great job on sticking with it and allowing the meat do its thing........


----------



## mayor mcpork (Mar 13, 2013)

I did have alarms set. The smoker hit 200 degrees one time during the night, but before I got out of bed, it ticked back up to 210 (it was 25 degrees, windy, and sleeting). Once morning hit and I bumped up the temperature, I increased my low temp alarm to 240 when I was gunning for the 250-265 range.

I'm using a cheap Masterbuilt propane smoker. The pork shoulder came straight from the store on Thursday, wasn't frozen, and sat in my fridge for 24 hours with the mustard/rub on it. For the entire smoke, I left the vent closed the entire time. My smoker doesn't have an intake outside of the air that sneaks in the bottom where the burner resides.

After it came out of the cooler, the bark looked fantastic. It was dark but not burnt. I located the shoulder and pulled it out without even twisting. Not a shred of meat on it. It pulled perfectly and tasted great. I honestly loved the taste, especially the bark. I know this all sounds odd and that's why I'm confused too.

I tested all of my thermometers afterwards so I doubt they were wrong. I'll concede that it's possible that the grate probe may have been induced to give lower readings somehow. It was placed on the top grate, about 3 inches from the back of the smoker and about 3 inches from the pork shoulder.


----------



## fpnmf (Mar 13, 2013)

1000x500px-LL-356f16fd_ThreadisUseless.jpg



__ fpnmf
__ Jan 26, 2013


----------



## michael ark (Mar 14, 2013)

Well at least it did not make you sick . You need to check out 4 /140 guide lines. I agree with everyone else something was up.


----------



## jarjarchef (Mar 14, 2013)

I am not sure......as I am scratching my head thinking......... I know I open my vent all the way to allow the smoke flow and not get stale...........not sure if that would give you a false positive on your temp readings.......... I know there is a big difference in cook times when cooking at 250 vs 225......;; maybe with being below 225 for a long period of time it effected it even more the other way........... My vote is for you to do it again and see what happens........... I would not cook at 225, I know it is traditional, but I like my time and the assurance I will get it through the TDZ in a timely manor............

The 40 to 140 in under 4hr guideline was mentioned....... Yes I would recommend familiarizing yourself with it. But if I understand your prep method you did not cut or inject the butt.... So in reality the guideline does not apply to intact whole mussels........you should be fine but 9hrs in the TDZ is a bit long in my world


Jeramy


----------



## mayor mcpork (Mar 14, 2013)

Yup, I'm well aware of the botchalism issue but it was whole muscle and I didn't score the meat, just took off a chunk of the fat cap.

I have gotten into the mode of not opening the vent because I've found that it allows me to maintain TBS longer without burning up my wood - less flame from my propane to maintain ideal temps. I know this whole things sounds weird. That's why I thought I'd post it. I've got another pork shoulder sitting in my old freezer. I'll bring that out in a few weeks and give it another go but will try a few new things. Thanks!


----------



## seenred (Mar 14, 2013)

Like everyone else, this sounds like false readings to me.  The fact that it pulled so easily and the blade slid right out would seem to indicate a butt that was at or near the optimum 200-205 IT.  I don't think it would be that tender and easy to pull if it was closer to 176-186 IT.   So... if you're sure of your therms, its a mystery.  
	

	
	
		
		



		
		
	


	





    200-225 does seem a little low for a butt cook, but not to the extent of such a large disparity in cook time.  Try the next butt at 250 minimum cooker temp and let us know how it goes.


----------



## daveomak (Mar 14, 2013)

Mayor McPork said:


> Yup, I'm well aware of the botchalism issue but it was whole muscle and I didn't score the meat, just took off a chunk of the fat cap.
> 
> *I have gotten into the mode of not opening the vent because I've found that it allows me to maintain TBS longer without burning up my wood -* less flame from my propane to maintain ideal temps. I know this whole things sounds weird. That's why I thought I'd post it. I've got another pork shoulder sitting in my old freezer. I'll bring that out in a few weeks and give it another go but will try a few new things. Thanks!


Mayor, morning.....  Not opening the vent allows for no air flow.... This smoke could have been different from others but, no air flow, there is no heat transfer to the meat......  The zone around the meat is cooled from the meat... Air flow is similar to a convection oven... Moving the heat around and moving the cold air trapped against the meat to a different area of the smoker....    With the vent closed, and no place for moisture to escape.... and in essence you end up steaming the meat.... In My Humble Opinion...      Dave


----------



## bbally (Mar 14, 2013)

Water activity hysteresis equilibrium stall.

Mallard reaction takes place at all temperatures. Just slower when lower. 

Basically the water activity reaches a resonant frequency where energy in equals energy passed through. Evaporation stalls so time rise stalls. Easiest way to change it stab it with a big steel fork in a couple places. Breaks the bark moisture loss will return oscillation will break and temp rise will start again. Although it you get it to do this it will be some damn tender meat it you wait.


----------



## mdboatbum (Mar 14, 2013)

jarjarchef said:


> The other thing that raises a flag for me is the final cook temp reading you got......you should not of been able to pull it at 176.......


After 36 hours in the smoker, I'd think you could pull it apart at 145˚. The thing about connective tissue breaking down is that it's a product of both time and temperature. The more time, the less heat required.

All that being said, get your smoker a little hotter. No need to risk getting sick.


----------



## sound1 (Mar 14, 2013)

I think Dave may be on to something. If you think about it, at normal pressure, water will not get above 212. Hence the water test on our probes. The meat is evaporating moisture as it cooks and as a guy that uses a "swamp" cooler in the summer, I can attest to the cooling effectiveness of evaporation. I am also a strong believer that it also is a major factor in the stall. 

I can see where a lack of air flow could cause a "micro-climate" of cool air enveloping the meat.

Combined with Dave, I think you're up to $.04 in the kitty.


----------



## daveomak (Mar 14, 2013)

bbally said:


> Water activity hysteresis equilibrium stall.
> 
> Mallard reaction takes place at all temperatures. Just slower when lower.
> 
> Basically the water activity reaches a resonant frequency where energy in equals energy passed through. Evaporation stalls so time rise stalls.* Easiest way to change it stab it with a big steel fork in a couple places. Breaks the bark moisture loss will return oscillation will break and temp rise will start again.* Although it you get it to do this it will be some damn tender meat it you wait.


I think I understand what you said....  *http://www.lsbu.ac.uk/water/activity.html  *

I'll have to read and re-read that a few times to get a handle on it...  

Stabbing the meat with a fork, does that help to "skip over" the stall ??

Dave


----------



## redneck69 (Mar 14, 2013)

the outside temp and wind was your issue if you didnt have it sheltered with a wall or something like that, the cold weather was sucking all the heat out of your smoker..on my MES 40 i put a welding blanket over top of it, i keep the exhaust port open of course, for cold weather overnight smokes


----------



## cliffcarter (Mar 14, 2013)

Mdboatbum said:


> After 36 hours in the smoker, I'd think you could pull it apart at 145˚. The thing about connective tissue breaking down is that it's a product of both time and temperature. The more time, the less heat required.
> 
> All that being said, get your smoker a little hotter. No need to risk getting sick.


I agree, I have had pullable butts as low as 182°, I no longer go by temp but by feel, temp is only a guide line IMHO. 


redneck69 said:


> the outside temp and wind was your issue if you didnt have it sheltered with a wall or something like that, the cold weather was sucking all the heat out of your smoker..on my MES 40 i put a welding blanket over top of it, i keep the exhaust port open of course, for cold weather overnight smokes


The most reasonable answer to your "problem" so far IMHO.


----------



## maple sticks (Mar 14, 2013)

I took a look at that site Dave, Seems right. If you run your meat through a dehydrator before smoking there is no stall and bacteria growth is inhibited. Sounds yummy.


----------



## cliffcarter (Mar 14, 2013)

Maple Sticks said:


> I took a look at that sight Dave, Seems right. If you run your meat through a dehydrator before smoking there is no stall and bacteria growth is inhibited. Sounds yummy.


There is no stall if you cook at 325°-350° also.


----------



## mayor mcpork (Mar 14, 2013)

Wow, great replies.

I've always figured that my cheap Masterbuilt was pourous enough since smoke billows out from every shoddy weld joint! Point made though, especially in the cold/wind/rain that I probably should open that vent some and crank the heat more. I suppose I was being miserly and trying not to waste extra propane. The tradeoff might have been that I wasted time instead of propane.

The end of the story is that the pulled pork dinner that my inlaws and family gathered for, turned into a Plan B trip to the Thai restaurant for take-out...that wasn't cheap!


----------



## bbally (Mar 14, 2013)

DaveOmak said:


> bbally said:
> 
> 
> > Water activity hysteresis equilibrium stall.
> ...



Yes anything that disrupts the thermal energy current moving in the same path does it. Sometimes just flipping them is enough


----------



## bbally (Mar 14, 2013)

cliffcarter said:


> Mdboatbum said:
> 
> 
> > After 36 hours in the smoker, I'd think you could pull it apart at 145˚. The thing about connective tissue breaking down is that it's a product of both time and temperature. The more time, the less heat required.
> ...



That is correct. Maillard reaction takes place at all temperatures it just takes longer.


----------



## bbally (Mar 14, 2013)

DaveOmak said:


> bbally said:
> 
> 
> > Water activity hysteresis equilibrium stall.
> ...



You will need to review a little on fluid oscillation as well.   The water activity goes high and low as the infrared energy pushes from molecule and exits to the next. If they reach resonance where the energy added by the heat source equals the energy into the item heating which equals the energy leaving the item and that matches the energy leaving the heat box you can have a stall. 

We are just using thermal transfer which is a set of frequencies same as music.


----------



## bbally (Mar 14, 2013)

cliffcarter said:


> Maple Sticks said:
> 
> 
> > I took a look at that sight Dave, Seems right. If you run your meat through a dehydrator before smoking there is no stall and bacteria growth is inhibited. Sounds yummy.
> ...



This is caused by being so far above the water activity boiling point. You move from slow water activity to the higher level in the steam tables. All cooking is water activity, temperature decides what phase the molecule is in. Sometimes referred to as state.


----------



## reinhard (Mar 15, 2013)

lot of good ideas on this mystery but i think i would go with Dave and Redneck with  this one, even though they had different ways to present it, i think the messege sounds reasonable.  i have a Masterbuilt electric that is digital. i have no problems in cold weather with it for it is insulated well. i did a 8 pound butt in 10 hours at 240 deg. and pulled it at 205 int. wrapped and let it rest and pulled. not being an expert with the mechanics i think the cold weather had something to do with the butt taking so long because the gas Masterbuilt the original poster has is not insulated at all. i also kept my vent open the entire time of the cooking cycle. i'm a sausage head and a rookie when it comes to this type of smoking but that's my opinion. Reinhard


----------



## baconologist (Mar 15, 2013)

bbally said:


> Water activity hysteresis equilibrium stall.
> 
> Mallard reaction takes place at all temperatures. Just slower when lower.
> 
> Basically the water activity reaches a resonant frequency where energy in equals energy passed through. Evaporation stalls so time rise stalls. Easiest way to change it stab it with a big steel fork in a couple places. Breaks the bark moisture loss will return oscillation will break and temp rise will start again. Although it you get it to do this it will be some damn tender meat it you wait.





bbally said:


> Yes anything that disrupts the thermal energy current moving in the same path does it. Sometimes just flipping them is enough





bbally said:


> That is correct. Maillard reaction takes place at all temperatures it just takes longer.





bbally said:


> You will need to review a little on fluid oscillation as well. The water activity goes high and low as the infrared energy pushes from molecule and exits to the next. If they reach resonance where the energy added by the heat source equals the energy into the item heating which equals the energy leaving the item and that matches the energy leaving the heat box you can have a stall.
> 
> We are just using thermal transfer which is a set of frequencies same as music.





bbally said:


> This is caused by being so far above the water activity boiling point. You move from slow water activity to the higher level in the steam tables. All cooking is water activity, temperature decides what phase the molecule is in. Sometimes referred to as state.


Can you please back-up what you've posted with some relevant references and translate it to layman's terms?

Thanks!


----------



## daveomak (Mar 15, 2013)

[color= rgb(128, 0, 0)]*http://www.lsbu.ac.uk/water/activity.html   *[/color]

There is the link I looked up because I needed some clarification.....  and it has been posted in many posts in this thread...  

By the way, bbally is a professional cook.....   and a very good guy....  He wouldn't try to B.S. you with anything related to food.....

Maybe with other stuff but not food related subjects.....  Please read his signature line... 

Dave


----------



## bbally (Mar 15, 2013)

Baconologist said:


> Can you please back-up what you've posted with some relevant references and translate it to layman's terms?
> 
> Thanks!


Would love to, but that requires you to have a degree in Spectroscopy or we are going to be here for a long time.  As far as amylase and Maillard, just look em up.  You will be surprised what you learn doing a little research to educate yourself on something someone said.  Then ask questions if you don't understand something.

But basically all cooking is thermodynamics.  More specifically the exchange of energy in the infrared spectrum.  Everything has a resonant frequency.

To "see it"

Watch this video of Galloping Gertie  

This is an example of an oscillator going into a resonance mode.  Here the wind represents the heat (infrared wave of your cooking source) and the bridge represents the meat you are cooking.

As you watch the amplitude of the wave (the bridge bucking harder and higher) you will see a close up of the cable (looks like a pipe line but it is actually the casing of the bridges suspension cables) moving in a countable pendulum pattern,  (This is the frequency, in this case very low frequency) as the wind (your heat source) adds energy you watch the bridge rise and fall harder and harder.  All resonance oscillators gain in amplitude if you add more power.  The bridge is shifting the energy from side to side.  Finally you see complete mechanical failure of the steel when the amplitude exceeds the strength of the steel.  Causing the energy to be released in a violent mechanical failure.

That is an oscillator.  Much much much faster the water inside you meat is doing the same thing.  If one could tune the wind to a specific speed the bridge would oscillate at the same rate forever if the loss matched the energy the wind was putting into it.  This is what happens with a water activity stall when resonance is reached.  (This is what the stall is, nothing magic, just science.)  In most case the energy coming into the meat is equal to the heat loss leaving the meat and the cooker happens to be adding and losing the same amount of heat.  Adjustments will change this, opening the damper will cool the meat (bad) increasing the temperature will start a new resonance pattern (what we would do in the Southern Pride smoker if we stalled as we know the stall is not magical but a pain since we have to serve on time.) Or you could disturb the oscillator by flipping it with a good squashing, or stabbing it with a fork.  (if the bridge had steel added to it the amplitude of the wave would change.)  Anyway point is a stall is nothing...... you don't have to wait just crank the heat for half an hour or so, or stab the meat or flip the meat... but don't just wait there, backyard lore says oh you just have to wait it out.  That is BS spread by people that subscribe to magic, not science.  Kill the stall and move on.

Change the function of the oscillator stops the stall.  Most commonly people will watch a stall for a long time thinking it is some kind of magical moment.  Stab the crap out of it with a fork, or pull it and mash on it a little and you can skip the stall.  In the commercial world this is no we will feed you tomorrow sometime since the meat stalled, there is get it done on time.  So we don't wait for a stall to stop, we either stab it or kick the heat up from 250 to 325 for about an hour and it is over.  In the backyard realm there is reverence for the stall, but it is just since and a pain in the butt!

If you pick up a college text on thermal dynamics you will become a much better cook IMO.  Even if you just read the beginning stuff on energy transfer.

Been a chef for 35 years now, started as one, been a practicing engineer for 28 years now.  One pays the bills one relieves the stress!  Cooking relieves the stress and has lots of interesting science in it.


----------



## diggingdogfarm (Mar 15, 2013)

Huh? :icon_eek:
I thought the stall was due to evaporative cooling?



~Martin


----------



## bbally (Mar 15, 2013)

DiggingDogFarm said:


> Huh?
> 
> 
> 
> ...


No it is not.  But the effect of evaporative loss could be observed around the meat because the meat is transferring energy out to a cooler area.  (Infrared energy moves from higher energy to lower energy.  But for the stall to happen it has to be happening at resonant frequency.  Some meats won't stall internally they are too dissimilar to oscillate.


----------



## diggingdogfarm (Mar 15, 2013)

Well, according to other "scientists" it is!!! LOL
Are you saying that evaporative cooling does not occur in a smoker?

~Martin


----------



## bbally (Mar 15, 2013)

DiggingDogFarm said:


> Well, according to other "scientists" it is!!! LOL
> Are you saying that evaporative cooling does not occur in a smoker?
> 
> ~Martin


Evaporative cooling is the loss of heat from one source to another.  IE in a swamp cooler where aspen pads or a man made material is wetted, air drawn through the pads.  The air going through the pads gives up some of its Infrared energy (heat) to water in the pads. (water loves heat, it is also what cooks) Which causes a delta T loss across the pad area making the air going into the house cooler than the air outside.

So to answer your question evaporative cooling works.  However inside a cooker the delta T would be the difference between the temperature of the air and smoke in the cooker and the temperature of the meat.

Which also means since the meat is lower than the temperature of the cooker that the meat is acting to absorb infrared energy.  So there will be a temperature gradient around the meat.  But it is not doing what people think it is not a cooler, but a heat sink.

This in a stall stops as the bark or outside coating has an isolative property to it which hampers heat moving into the meat.  It also hampers heat release should it be necessary.  (bottom overheating due to fire exposure or reverse flow indirect heating plate (element) so the water activity tends to become more and more isolated.


----------



## diggingdogfarm (Mar 15, 2013)

What do you think about smoking at wet-bulb temperature and is wet bulb temperature a good indication of meat surface temperature.?


~Martin


----------



## bbally (Mar 15, 2013)

DiggingDogFarm said:


> What do you think about smoking at wet-bulb temperature and is wet bulb temperature a good indication of meat surface temperature.?
> 
> 
> ~Martin


Most smokers are at saturation for the running temperature.  So IMO you are so close to 100 percent humidity inside a well designed and/or manufactured smoker that you are always going to be at wet bulb anyway.  So just measure with a temp probe be within a few degrees.  Certainly less than the error in most temp probes..  (jerky driers don't count as a smoker!  and I have seen some homemade designs that are jerky driers disguised as a smoker cooker.)

Wet bulb is not a good indicator of the meat surface temperature.  It is a good indication of what the meat is seeing for outside temp, but thermal transfer is immediate so technically meat surface is always slightly under the surrounding temperature.  (Unless you cook like Piney.... once it goes char and catches on fire it is all the same temperature!  FLASHPOINT!  LOL!)


----------



## diggingdogfarm (Mar 15, 2013)

In my experience, that's not the case in most smokers.
There is a definite difference between the dry-bulb and the wet-bulb temperature.
I think I'm going to stick with what a very well known physicist, other scientists and the USDA say.


~Martin


----------



## bbally (Mar 15, 2013)

DiggingDogFarm said:


> I think I'm going to stick with what a very well known physicist, other scientists and the USDA say.
> 
> 
> ~Martin


Cool.


----------



## mayor mcpork (Mar 15, 2013)

....and that concludes today's class on thermal dynamics. Thank you all for coming. Please tip your waitstaff.

(Applause)


----------



## diggingdogfarm (Mar 15, 2013)

bbally said:


> Wet bulb is not a good indicator of the meat surface temperature.



Hmmm!
That's opposite what others say, including the USDA.



~Martin


----------



## bbally (Mar 15, 2013)

DiggingDogFarm said:


> Hmmm!
> That's opposite what others say, including the USDA.
> 
> 
> ...


I won't try and guess what the circumstances are that created the USDA decision to go with wet bulb.  I assume since humidity is a good indicator of thermal transfer they like it for cooking application to keep the convection oven users honest?


----------



## bbally (Mar 15, 2013)

Mayor McPork said:


> ....and that concludes today's class on thermal dynamics. Thank you all for coming. Please tip your waitstaff.
> 
> (Applause)


Ladies wanting an A in the class please see the professor after class!! lol


----------



## diggingdogfarm (Mar 15, 2013)

It's among the compliance guidelines for some pathogen lethality treatments because wet-bulb temperature is a more accurate measurement of product surface temperature.


~Martin


----------



## lu1847 (Mar 15, 2013)

Wow my ears are smoking.  I think I'm more confused now then before I read the post.  All good info that I guess a guy just has to research for himself.  Thanks guys!


----------



## baconologist (Mar 15, 2013)

bbally said:


> Would love to, but that requires you to have a degree in Spectroscopy or we are going to be here for a long time.  As far as amylase and Maillard, just look em up.  You will be surprised what you learn doing a little research to educate yourself on something someone said.  Then ask questions if you don't understand something.
> 
> But basically all cooking is thermodynamics.  More specifically the exchange of energy in the infrared spectrum.  Everything has a resonant frequency.
> 
> ...



I'm extremely skeptical.

I'm going to side with those who say the stall is caused by evaporative cooling.


----------



## jarjarchef (Mar 15, 2013)

OK my head is spinning after reading the rest of this.....

So if I understand what I have read (not saying I do). Stall is bad and should be destroyed at all cost and the best way to destroy it is to change something by either moving it, stabbing it or adjusting the temps...... but what about the "Texas Crutch" of wrapping the meat???? does that fall into changing the rhythm of the pattern???.....I am not a big fan of stabbing meat because it releases the natural juices.....but I am game to try new things.........

But it sounds like some of the old school Chef's I have worked for were on to something without even knowing it......they always told me if what I am doing is not getting the results I want, then change something the temp, position or even the oven if needed......

Great info guys....


----------



## pc farmer (Mar 15, 2013)

This is good reading material.   Will every piece of meat stall?


----------



## jirodriguez (Mar 15, 2013)

c farmer said:


> This is good reading material. Will every piece of meat stall?


No... things like chicken or lean cuts wont stall. Usually the stall occurs in large cuts containing fat and connective tissue.

Also keep in mind all this occured on a cold windy day which is about the hardest temp to maintain a chamber temp in if you don't have some sort of insulator around your smoker. I used to use my WSM in the middle of cold windy rainy days here in OR, and would run into similar situations. Then I bought a welding blanket to wrap my smoker in and got much better temp readings and efficiency on long smokes.


----------



## bbally (Mar 15, 2013)

Baconologist said:


> I'm extremely skeptical.	I'm going to side with those who say the stall is caused by evaporative cooling.



That is good I don't share this to convince.  I only want people to think.


----------



## bbally (Mar 15, 2013)

DiggingDogFarm said:


> It's among the compliance guidelines for some pathogen lethality treatments because wet-bulb temperature is a more accurate measurement of product surface temperature.
> 
> 
> ~Martin



Sure that makes sense. But for smokers I feel there is no need. Humidity is so high in low and slow cooking that I would not expect much of a difference. Next time I fire up the rig I will through a set of dry wet probes in and see what the difference is.


----------



## bbally (Mar 15, 2013)

jarjarchef said:


> OK my head is spinning after reading the rest of this.....
> 
> 
> 
> ...



Wrapping changes the Water Activity though you can see a stall continue occasionally because the wrap can act as a artificial bark. Changing temp works real well getting up toward 325 F usually kicks it off. 

Stabbing always works. But you can lose moisture from the meat. I pan so it does not affect what I am doing.


----------



## diggingdogfarm (Mar 15, 2013)

I sure would like to get to the bottom of this.
If the physicists, meat and food scientists as well as the USDA are all wrong, I want to know.



bbally said:


> DiggingDogFarm said:
> 
> 
> > What do you think about smoking at wet-bulb temperature and is wet bulb temperature a good indication of meat surface temperature.?
> ...






bbally said:


> DiggingDogFarm said:
> 
> 
> > I thought the stall was due to evaporative cooling?
> ...



_"Because moisture is evaporating from the product surface during cooking, the surface of the product acts much like a wet-bulb sock. *Evaporative cooling of the product surface keeps the surface temperature at or near the oven wet-bulb temperature for much of the cooking process. Since the oven wet-bulb temperature has a strong influence on the product surface temperature, it also has a strong influence on the surface-to-core temperature difference that determines product heating rates and cooking times. For this reason, the oven wet-bulb temperature essentially controls the product heating rate for much of the cooking process, and is a critically important heat transfer variable."*

"During the wet-surface phase of a process, the product behaves as though it is being heated in a water bath that is at the wet-bulb temperature.* Any change in the wet-bulb temperature will have an almost immediate impact on the product surface temperature. As long as the product surface is completely covered with a thin layer of moisture, the wet-bulb temperature essentially controls the product surface temperature and heating rate,* while the dry-bulb temperature has little or no effect."

"The higher surface temperature increased the surface-to-core temperature difference, and as a result, the product-heating rate for this process was faster than it would have been had the surface stayed wet. *If the product surface had stayed wet throughout the process, the constant rate of evaporative cooling would have caused the surface temperature to stay at the wet-bulb temperature for the entire process, resulting in a smaller surface-to-core temperature difference and a longer cooking time.*"

"*Of course, an easy way to increase the heating rate for this process would have been to increase the wet-bulb temperature. This would have resulted in an immediate increase in the surface temperature and the surface-to-core temperature difference, thus creating a faster heating rate.* An increase in the dry-bulb temperature would have also eventually increased the surface temperature and the heating rate. But because it would have taken time to dry the product surface and allow the surface temperature to increase above the wet-bulb temperature, the effect would not have been as immediate as an increase in the wet-bulb temperature."_

Source: http://www.alkar.com/technical_reports/cooking_truth.html

~Martin


----------



## jarjarchef (Mar 15, 2013)

bbally said:


> Wrapping changes the Water Activity though you can see a stall continue occasionally because the wrap can act as a artificial bark. Changing temp works real well getting up toward 325 F usually kicks it off.
> 
> Stabbing always works. But you can lose moisture from the meat. I pan so it does not affect what I am doing.



Thank you for the info.......I have learned something new"....I don't think everything stuck, but I did get a different view of how food cooks.........

I will stick with my no wrapping and cooking at 250-275....... Seems to have little or no stall, but if I get a longer stall then wanted or can afford I now have ways to address it....... Thank you....


----------



## bbally (Mar 15, 2013)

DiggingDogFarm said:


> I sure would like to get to the bottom of this.
> If the physicists, meat and food scientists as well as the USDA are all wrong, I want to know.
> 
> _"Because moisture is evaporating from the product surface during cooking, the surface of the product acts much like a wet-bulb sock. *Evaporative cooling of the product surface keeps the surface temperature at or near the oven wet-bulb temperature for much of the cooking process. Since the oven wet-bulb temperature has a strong influence on the product surface temperature, it also has a strong influence on the surface-to-core temperature difference that determines product heating rates and cooking times. For this reason, the oven wet-bulb temperature essentially controls the product heating rate for much of the cooking process, and is a critically important heat transfer variable."*
> ...


Please clarify with your USDA reference.  That is the one I will read.

The stall is not caused by evaporative cooling.  It is caused by temperature and water activity equilibrium.

Where I tell you No wet bulb is not a good indicator of the temperature the meat sees.  I am speaking of smoker cookers.    Were radient infrared is as big part of the process as the humidity.

The reference you listed is a cooking equipment company's sales information it contains no scientific data for reference.  It is marketing information presented as science and while based in scientific principal and does apply in certain cooking apparatus it by no means an industry standard.  Though it is useful it it gets you to buy their equipment.  And does follow principals I have explained, such as increasing humidity increases water activity.  Though it tries to sell it as magic their process equipment can do... but really placing a bowl of water in a standard oven will also do it.  Since the partial pressure of water causes evaporation when the air is not saturated.

Again I am speaking to the commercial smoker cooker.  Which is usually at dew point when up to temp so the dry and wet bulb temperatures are no different.

If you want to talk about a commercial cured and mixed meat processor that controls dry temperatures, (for setting texture) humidity (for different cured products to be handled) and air flow (forced convection temperatures for controlled water loss in products) you can set up parameters where a wet bulb temperature is what the meat "may see" though it ignores the radiant energy the meat absorbs from the infrared spectrum.

But link your USDA source, be happy to read it and give you my thoughts.


----------



## mountainhawg (Mar 15, 2013)

I would like to know ambient air temperatures and wind. I have seen some large influences on cooking wit large night temperature drops and wind increased affecting my cooking up here on this mountain. 

Even though I was a meteorologist for over 41 years, I hate to touch that wet bulb discussion even though it seems to be quite interesting. Any water moisture on the meat would be mixed with oils, spices and other fluids and not evaporate like pure water on a wet bulb thermometer. Also to cool an object significantly due to evaporation, a fairly good flow of air would need to be present. To get a wet bulb temperature (and humidity) in meteorology, mounted dry and wet bulb thermometers are on a sling that is swirled in a circle or a fan is used.  

I am sure that while there is some cooling from evaporation, it would quickly be overcome/overwhelmed by the heat source of the grill/smoker when hot cooking.

If there was significant cool/cold airflow through the lower vents for any measurable evaporative cooling, I would think the greater affect would be advecting out the stack of the heat produced by 

heat source and heat of the item being cooked. So cooling would be accomplished much more thoroughly through loss of heat than evaporation. 

IF one was cold smoking (assuming using dry wood or pellets) the wet bulb effect would probably be greater due to a lack of significant heat to quickly counter evaporative cooling and would be a help to the person doing the cold smoke in warmish temperatures. It's all DEPENDENT on the ambient air's wet bulb' difference to the ambient dry bulb, simply put, how dry is the air.


----------



## diggingdogfarm (Mar 15, 2013)

bbally said:


> Please clarify with your USDA reference.  That is the one I will read.
> 
> The stall is not caused by evaporative cooling.  It is caused by temperature and water activity equilibrium.
> 
> ...



Okie, dokie!!!
A lot of the USDA's information doesn't contain  scientific data for reference either!!!!!
See the other thread that I started, search USDA info for compliance guidelines for some pathogen lethality treatments and search some meat and food science books online or at the library.

You're asking for scientific data for reference, but you haven't provided a shred yourself.

I'm finished with this conversation.

Thanks!!!!


~Martin


----------



## bbally (Mar 15, 2013)

jarjarchef said:


> Thank you for the info.......I have learned something new"....I don't think everything stuck, but I did get a different view of how food cooks.........
> 
> I will stick with my no wrapping and cooking at 250-275....... Seems to have little or no stall, but if I get a longer stall then wanted or can afford I now have ways to address it....... Thank you....


Stall is also influenced by the power of the smoker/cooker.

I have received calls in a lot of cases where a smaller wattage cooker/smokers and always stalling.  Sometimes the meat stops climbing in temperature not because of a water activity oscillation, but because the amount of heat loss from the cooker itself is so great there is not enough energy left over to bring the meat temperature up.  I believe someone else spoke to using an insulator around the smoker in Oregon.... this is a real concern as lower powered smokers/cookers can be put in an environment where they only have enough wattage to maintain temperature and not enough to keep the meat moving up in temperature.  Pretty easy to diagnose though... see if the element is staying on or the fire box is glowing well.. if so wrap something around it without covering its air ways and watch the temperature.  Mostly happens to electrics and small charcoal units.


----------



## bbally (Mar 15, 2013)

DiggingDogFarm said:


> Okie, dokie!!!
> A lot of the USDA's information doesn't contain scientific data for reference either!!!!!
> See the other thread that I started, search USDA info for compliance guidelines for some pathogen lethality treatments and search some meat and food science books online or at the library.
> 
> ...


I was asking because you sited USDA being wrong, just wanted to read what you read so I could comment.  I figured when you stated that USDA was wrong you had read a specific USDA guideline.

Thanks for the participation.  Keep on Cooking!


----------



## baconologist (Mar 15, 2013)

bbally,

Can you please provide a few scientific references on water activity hysteresis equilibrium as a cause of the BBQ stall specifically?
My wife is a scientist and I'd like to have her take a look.


----------



## bbally (Mar 15, 2013)

Have her start with:

Thermal Hysteresis of infrared spectra nod corn starch/Water Systems

Dr. Masaru Mizoguchi
Article first published online: 26 OCT 2006

DOI: 10.1002/star.19940460703

Copyright [emoji]169[/emoji] 1994 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

This was one of the first to use an FTIR spectrometer to observe the hysteresis of water activity in direct cooking conditions. The starch was used to understand the energy exchange as the starch would gel as specific energies.

I will add a couple more as I recall my research from a few years back.  When I am in my lab on Monday I will dig out the thermal imaging (FLIR) pictures of the pork butts I have them on a flash drive. Actually pretty interesting but at 20K for the instrument not exactly a home use item. 

A decent isotherm hysteresis explanation is summarized in:

Food Drying Science and Technology: Microbiology, Chemistry, Application
 edited by Yiu H. Hui


I will have to get to the lab on Monday I don't remember who started the work on large cut protein.


----------



## bbally (Mar 15, 2013)

Baconologist said:


> bbally,
> 
> Can you please provide a few scientific references on water activity hysteresis equilibrium as a cause of the BBQ stall specifically?
> My wife is a scientist and I'd like to have her take a look.



I thought you were in the swamp cooler camp?  Fun to try and figure out isn't it?

It will drive man nuts forever.  It started with mastodon barbecue when one cave man used sauce. And the caveman down the canyon used dry rub. The debate began and has continued on.  Of course both barbecue attracted ladies so everyone continued on.


----------



## baconologist (Mar 15, 2013)

Do you have any specific BBQ stall references?
That's what I'm looking for.


----------



## bbally (Mar 16, 2013)

To my knowledge there has been nothing done on barbecue itself.  But show the references to your wife. She is a scientist she will know how to use them in the scientific method


----------



## baconologist (Mar 16, 2013)

So, in relation to the BBQ stall, this is just your personal theory and you have no corroborative scientific or empirical  evidence?


----------



## bbally (Mar 16, 2013)

Baconologist said:


> So, in relation to the BBQ stall, this is just your personal theory and you have no corroborative scientific or empirical  evidence?



Corroborative science:

Of course the infrared heating method of food corroborates the stall.  That is long settled science. 

The water activity method by which all food cooks is also long settled science.

The laws of infrared thermodynamics is settled science.

The transference of infrared energy among water molecules is long settled science (also applies to evaporative cooling as well as pasteurization by sustained surface temperature)

The hysteresis of water activity in I infrared spectra is settled science. I sited the publication you can read on it. 

The hysteresis on thermal gain and loss is settled science and taught in universities across the world. 

The watt hours to raise one pound of water one degree F is settled science and the basis for all water activity calculations. (This is often expressed as btu capacity) 

The propensity of a molecules susceptibility to accept infrared energy is long settled science published in the steam table works for years. 

The amylase reaction is long settled science

The Maillard reaction is long settled science. 

The propensity of proteins converted by Maillard to reject infrared wavelengths is settled in material science under oxidation tables. 

The hysteresis of all wavelengths and all things is long settled science.

The thermal balance of all molecules is long settled science. In food it was put forth by Dr. Pasteurs to kill pathogens in milk. 

I can go on but why you ask questions with an agenda in mind not an open mind. You know what you want to believe so have at it.  Let others reading interested in learning read and maybe research a little. 

Empirical evidence:

I have observed the smoker cooker with FLIR through many cooking cycles and watched the infrared exchange

I have induced the stall by balancing the input energy with the escaping energy. 

I have watched the stall fall apart by interrupting the hysteresis cycle set up in the FLIR camera in real time. 

I have watched the hysteresis fall apart with thermal increase. A phenomenon observed by many. But I wanted to know why. 

Along with a whole host of variable controls and experimental tweaks to confirm the empirical data I was collecting. 


Other than that there is nothing. Lol. 

I look forward to your scientific method and empirical data that disproves the theory. If you take the time with your wife's help, you will be disappointed in the conclusion the data lead you too. 

Just for the record wet bulb temperature for sterilization of pathogens is settled science. The steam tables brought forth the use of saturated atmosphere for pasteurization of medical instrument decades ago.


----------



## bbally (Mar 16, 2013)

Now I was hoping someone would read and ask it but:

The swamp cooler theory breaks down under the laws of thermodynamics as the "cooling" should indicated heat loss. Which if true would result in the consistent lowering of the meat temperature. Which is not observed. 

Therefore the only way to have a temperature maintain stead is for the meat to also be accepting energy at the rate of loss. 

Which is the definition of an oscillator in hysteresis. 

Unless someone is interested in explains perpetual energy function of the meat in the stall then the laws of thermo dynamics say the meat has to be accepting energy and losing energy at the exact same rate. The very definition of a tuned oscillator.


----------



## baconologist (Mar 16, 2013)

I have no agenda in mind, I'm just asking for some specific authoritative and compelling evidence that supports your theory in relation to the BBQ stall.

It's a simple question.

There are several theories as to what causes the BBQ stall, the phase change when collagen converts to gelatin. evaporative cooling, fat rendering,  protein denaturing, and, of course, your personal theory. 

Again, in relation to the BBQ stall, can you direct me to some specific corroborative scientific or empirical evidence that supports your theory?


----------



## daveomak (Mar 16, 2013)

Baconologist said:


> I have no agenda in mind, I'm just asking for some specific authoritative and compelling evidence that supports your theory in relation to the BBQ stall.
> 
> It's a simple question.
> 
> ...


Baconologist....  It is time you reread your posts.....* http://www.smokingmeatforums.com/forums/posts/by_user/id/60750*

You are being rude, disrespectful and arrogant without a purpose....  

If you want to learn, there have been many pointers as to what to look for, and where to look....  Google is a good place to start...  

You sound like a member from the past, who had nothing positive to add to the forum, only disrespectful comments....


----------



## disturbed1 (Mar 16, 2013)

highly educational just got home from working a 12 hour shift. jumped on this thread and damn.

LOL!!! The knowledge on here is great.

Thanks bbally.


----------

