why would my temp run up on an all-night cook

tcampbell

cooked a butt last night started about 6 p.m. Got my temp. stabilize at 240 checked it at 10 p.m. still good checked at 1 a.m. still 240 checked 3 a.m. the temp had ran up to 360 what would cause that.The only thing I could think of is I started with a water pan and sometimes after 1 a.m. the pan ran out of water would that cause the temp to shoot up like that.From the time I got the temp regulated about 7 p.m. I never moved the top or bottom vents.its a xl egg

BOWHUNR

My first and pretty much only guess would be wind since you had it stable for so long.  I had it happen one too many times and bought a Digi-Q DX and a Maverick so I can get some sleep.

Mike 

FearlessTheEggNoob

The cooling effect of the butt wore off after 1am.

stemc33

+1 on the wind. If it wasn't the wind, it probably was directly related to air flow. My guess is that once the air flow increased, even if it was temporary, the fire got hotter. Once the fire got hotter, it increased the draw of O2 into the firebox which kept the temp rising. Similar to positive feedback.

RRP

I recall a few over night low & slows like that myself! Like @BOWHUNR said it probably was the wind unless you had gasket issues to compound it. OTOH no offense, but unless your egg is in a fire proof area then the turbo method during the time you are up and awake even beats a low & slow even with a Digi-Q or any monitoring devices while you are sound asleep!

tcampbell

RRP said:

I recall a few over night low & slows like that myself! Like @BOWHUNR said it probably was the wind unless you had gasket issues to compound it. OTOH no offense, but unless your egg is in a fire proof area then the turbo method during the time you are up and awake even beats a low & slow even with a Digi-Q or any monitoring devices while you are sound asleep!

Even with temp.running up it still turned out great.The reason for not turboing was a time issue,had it for lunch at work and couldn't cook it that morning.

SenecaTheYounger

Wind doesn't affect the egg draft to any degree enough for that climb. FearlesstheEggNoob is spot on.

Cold meat and the waterpan are heat sinks. Water can take on an enormous amount of heat energy, and if your vents were open too wide, the extra energy would be going in to trying to raise the water temperature. You aren't ever going to boil it at those dome temperatures, and so the entire time it is going to be capable of absorbing extra heat energy, and keeping the ambient temperature down.

When it has evaporated, that heat energy has to go somewhere.

I'll say again, continuous thirty mile an hour winds won't cause your temperature to run away. My summer egg gets wind from across a lake straight at it. When this picks up overnight, during a butt cook, as when a front comes through, there is no affect on the dome temperature.

We see a drop in dome temperature when we put meat in. But it recovers. The so called stall is nothing more than water being driven off (evaporative cooling). When the stall is over, the meat temperature rises.

Additional water will also keep the temperature down. But when it evaporates, there's nothing left in the pan to absorb the heat (like the meat does). And so the heat goes into the system itself

If you were to replenish it, it would help actually keep temperatures stable, because it won't ever get higher than below boiling. A nice hundred eighty to two hundred degree mass will do much to keep the system low and slow. This is afterall why water pans are used (they do not make food moist, but that's a discussion for another day).

So either keep it filled, or do what some do: stabilize vents and ditch the water pan

stevesails

This is afterall why water pans are used (they do not make food moist, but that's a discussion for another day).

oh my.. I learned something new today. 

NPHuskerFL

Ahhh yes Thermal Dynamics 101 ;-)

SenecaTheYounger

@stevesails:  Not sure if you are kidding or not.

But it is true.  Cooking in a wet environment (braising, boiling, etc.) doesn't add moisture to the meat.

It's counter intuitive, and boy it really seems like it would ad moisture, but if you have any doubts, just boil some fish or chicken until it is 180 or more internal.  It will be dry when you cut into it.

What cooking in a wet environment does do is slow the cook down.  You won't be cooking higher than 212 if you are boiling chicken.  And even though the water transfers heat much faster than air (which means it cooks faster in 212 degree water than it does in 212 degree air), it is still a relatively slow cook.  This is a gentler cook, and allows you much more control and much more time to catch the food in the proper window of internal temperature. 

Which means that you are preserving moisture in the meat, but not adding it.

But since moisture isn't added, you can still damage the meat to the point of dryness by overcooking.

So, the heat sink provided by a large water pan will help moderate the cooking environment.  But the water vapor doesn't get absorbed into the meat, making it more moist.

Anyone who has boiled a lobster or crab and found the tips of the claws dried out will understand that cooking water doesn't penetrate into the meat and add (or even rehydrate) the meat to the extent we are generally led to believe that it does.

Again, Harold McGee is a great source for explaining what is really going on when meat is being cooked.  Always a good read.

on braising: "McGee goes further, asserting that the primary tenderizer is not trapped steam or localized high pressure but rather sustained low temperature, ideally below the boiling point. When the internal meat temperature registers between 160 and 180 degrees, the collagen in tough connective tissue starts to dissolve into soft, unctuous gelatin, and the meat fibers, once bonded tightly together by the connective tissue, become easier to separate and, thus, more tender. To keep the internal meat temperature in the ideal collagen-melting range, McGee recommends setting the oven to between 200 and 250 degrees and keeping the pot lid slightly ajar. At an oven temperature as high as that which Kamman suggests, the outer portions of the meat will “overcook badly,” he contends."  (rather than thumbing through "On Food and Cooking", I found this quickly HERE)

He does say that allowing the meat to cool in the cooking liquid will allow it to reabsord some lost moisture, but this does not occur during the cook.  And not at all what a water pan would achieve.

To cook meat, in any manner, is to do cell damage.  This releases water on a cellular (i.e. micro)  level. After that, the meat is a sponge (i.e. macro level), and it is shrinking during cooking (or force during cutting while serving/eating) which squeezes water out. The only way to get water into the cells is to brine it, and let the salt do the work. But once out, the dry meat stays dry.  Even storing overcooked meat in water (like, when adding burnt tips to a stew or chili) means nothing more than meat which is wet on the outside and dry on the inside.

Cooking in a moist environment slows the cook, permits better control, less chance to dry out (because you have more time to properly take temperatures, and the thermal inertia is lower, less overrun).  You may end up with more moist meat, but it isn't because it is added moisture.  And you can still cook the meat utterly dry in such an environment.

tcampbell

Thanks to all

tcampbell

I was using the pan more for catching the drippings and keeping plate setter clean.

SenecaTheYounger

Drip pan alone is fine. Water can mess things up.

caliking

This happens when I use a water pan for a lo n slo overnight cook. The temp rises after the water evaporates, since it no longer acts as a heat barrier/sink.

bbqlearner

caliking said:

This happens when I use a water pan for a lo n slo overnight cook. The temp rises after the water evaporates, since it no longer acts as a heat barrier/sink.

+1 - water pan does affect temp.

stevesails

This is great info. Taking a step father. When doing beer can chicken the moisture on the can does nothing but keep the temp down?

Foghorn

stevesails said:

This is great info. Taking a step father. When doing beer can chicken the moisture on the can does nothing but keep the temp down?

There's probably a lot of truth to that.  I'm just theorizing here, but as the liquid boils/steams inside the cavity it probably also helps the chicken cook more evenly.

lousubcap

Here's a great read on beer can chix:  http://www.nakedwhiz.com/beercanchicken.htm  His main site is a wealth of ceramic cooking info.  Worth a good look.  FWIW-

SenecaTheYounger

The liquid in beercan chicken doesn't boil.  If it does, it's because you are cooking direct, and the bottom of the chicken will be incinerated.  If indirect, that liquid may evaporate, but not much.

Have no idea if it helps cook the chicken more evenly.  Perhaps.  You make a good point.  Without a can, the surrounding air would be whatever the dome temperature is, maybe 400 all sides, inside and out.  With a liquid filled can in place, as a heat sink, the outer flesh is being bathed in 400 degree air, but the inner side of the breast is at 200 ish.

Probably does help keep it juicier that way (less chance to overcook).

It may flavor somehow, by depositing vapor on the outside of the chicken.  But the inner cavity of the carcass is lined with a waterproof pleural lining. This is the same lining we remove from pork ribs.

No water or flavor is getting through that, it's designed to hold the pleural fluid when that chicken is walking and squawking.

So, the beer can helps the chicken stand, may help moderate the heat (by tempering how hot the interior gets), but it doesn't add any more flavor than what you'd get by using a water (or beer-filled) pan with the same ingredients in it. Any deposited flavor comes from evaporation, if at all.  There's no boiling, unless the set up is direct (probably a bad idea), or there is a very small amount of liquid.

Little Steven

I think it's just the low volume of liquid and smaller diameter of the pan as compared to a water pan.. It is true that you don't actually lose water to evapouration in a beer can chicken.

caliking

The beer can chicken deal was sort of debunked a year or two ago on amazingribs.com or some site/blog like it. I stopped doing those because it was a hassle. However, it still looks cool to guests when you show them a chicken standing with a beer can up its butt.

Eggcelsior

caliking said:

The beer can chicken deal was sort of debunked a year or two ago on amazingribs.com or some site/blog like it. I stopped doing those because it was a hassle. However, it still looks cool to guests when you show them a chicken standing with a beer can up its butt.

Little Steven's version is even better.

The Naked Whiz

Foghorn said:

stevesails said:

This is great info. Taking a step father. When doing beer can chicken the moisture on the can does nothing but keep the temp down?

There's probably a lot of truth to that.  I'm just theorizing here, but as the liquid boils/steams inside the cavity it probably also helps the chicken cook more evenly.

The liquid in the can does not boil, and it barely steams. 

gerhardk

I always stabilize the egg when it is empty, no food, no plate setter, once I add those things the temperature goes down for a long time (an hour plus) but it does not go much above the stabilized temperature.  I have no trouble with drying the meat and use no water pan.  As far as beer can chicken in my experience you get a more even cook with a spatchcock chicken.

Gerhard

Foghorn

So the liquid in the beer can never reaches boiling temp?

lousubcap

@foghorn-Here's a great read on beer can chix:  http://www.nakedwhiz.com/beercanchicken.htm  His main site is a wealth of ceramic cooking info.  Worth a good look.  FWIW- posted above >-

Foghorn

@lousubcap,

Thank you.  I thought I had read pretty much everything at that site but I guess not. I love that he puts science into this.