Naive Question: How is food cooked on log burners/offsets not inedibly smokey?

[Michael_in_TX]

By coincidence I've been watching several videos of people using offsets or other log burners. I've noticed there tends to be a typical setup procedure for the fuel: a moderate bed of charcoal onto which one places a wood split and then replenishes that wood split regularly throughout the cook.

Now, on my PBC and my Weber Kettle, I have to be very careful about how much wood chunks I use. Any more than two handfuls of ~6 oz chunks, especially hickory, and I am in danger of over-smoking my food.

Yet, on a log burner, 12 oz of wood is quite smaller than a single wood split! And I certainly don't replenish throughout the cook.

So how isn't the food on an offset inedibly smokey? Is it the cooking chamber volume (offsets and other log burners tend to be quite large, of course)....is the airflow speed? I've noticed that most offsets have relatively large smokestacks.

[Jerod Broussard]

Over smoked in my opinion is over thinking. Only so many smoke particles can adhere to that surface.

[DogFaced PonySoldier]

I dunno, I've had some stickburner-cooked meats that were so smoky I could barely stomach them. Maybe it was dirty smoke/soot, I dunno. All I know is I didn't care for them at ALL.

[texastweeter]

Nah they can keep building up, just like creosote in your pit.

[SchweinStein]

You got part of the answer in that airflow speed is part of the reason. I think the biggest reason is the "type" of burn. If the cook knows how to use his smoker, the offset will be fully combusting the wood and virtually no white smoke will be coming out of the stack. Whereas with other smokers, and for example the kettle, the wood tends to smolder more. Smoldering and under-burning can produce more undesirable flavors associated with oversmoking. This is compounded by the fact that the airflow is slow and the smoke is trapped in the cooker for a longer period of time.

If you want to read a more in depth explanation Meathead has a good article found here:

https://amazingribs.com/more-techniq...ood-smoke-and/

[Henrik]

It’s a good question. The short answer is: combustion temperature. The fire in a kettle or kamado is just smoldering or very slow burning. That means the combustion temp is slow, creating ‘dirty’ smoke from the few chunks of wood you add. With an offset with good draft, the combustion temp is much higher, so it evens out in the end. The VOCs (Volatile Organic Compounds) in wood add flavor, and when the wood burns hotter they burn, leaving ‘less’ smoke flavor. I just did a YT video on this, let me know if you want a link.

[willxfmr]

Henrik I'd love to see the video if you wouldn't mind sharing the link. I don't own an offset any more, but that might change someday.

[Henrik]

Here it is willxfmr : https://youtu.be/64MaYxAtGls

[Michael_in_TX]

Henrik, that was *incredibly* instructive and answered my question perfectly! Thank you so much for taking the time to film that.

[Jerod Broussard]

Henrik I would believe you if you had used at least some stoichiometry, and I had never smoked in a cheap offset that was notorious for pathetic air flow.

[Steve B]

Stoichio what???

[texastweeter]

Lol. Short answer 14.7 to 1 for gasoline engines

[Steve B]

That’s funny AF texastweeter But only car guys would understand that.

[Michael_in_TX]

Thanks all and the combustion temperature plus airflow makes sense. It just hit me as I was watching those videos: waitaminute, if I put a split in my PBC, the food would taste like wood!

[Mr. Bones]

Quite possibly so, ain't got a PBC to verify...

BUT, if ya made ya a burn barrel, an fed yer PBC coals from splits, might be a really tasty kinda experience...

[Mr. Bones]

I dunno...

I jus throws me some hickory, mesquite, etc. et. al into mine, an sets th knob on "Low Smoke"...

Never feel abashed or shy bout askin a question round these here parts, Brother!

(Reckon I done asked up alla th Stoopid ones, long afore ya got here!)

[CaptainMike]

As requested from Henrik here's my structure fire analogy. There are 4 basic phases of a structure fire: 1) the incipient phase when a fire is ignited, 2) the growth phase where a fire starts consuming combustibles, 3) the free burn phase where most or all of the combustibles are being consumed, and 4) the decay or smoldering phase where most of the available oxygen in an enclosed environment has been used and combustion gasses accumulate without burning.

In smoking food we're in the 3rd and/or 4th phase. Because we're using sticks instead of charcoal, offsets perform best in the 3rd phase were there is live fire, air movement, and partial combustible gas consumption (thin blue smoke). The main function of an offset is to move heat and smoke from the fire box across the cooking chamber and out through the vent.

Kettles, barrels, kamados, etc when using slow burning charcoal tend toward the smoldering phase where heat, smoke and water vapor linger in the cooking chamber and are expelled more slowly. Due to the increased level of incomplete combustion and decreased air movement there are more smoke particles available to adhere to our food. This is also the reason why we should "burp" a cooker to prevent a smoke explosion (backdraft) when we see the combination of copious dirty smoke and high heat. If you've ever had the hair on your forearms singed when opening a kettle then you know what I mean.

Of course the variables are almost infinite and the conditions can easily be flip flopped with any style of cooker, but these are the observations of an old fireman and his smokers.

[Henrik]

Thanks Captain!

[texastweeter]

You would think this guy knows a thing or two about fires...

[texastweeter]

Faster airflow, and when ran properly it is a much hotter fire with more complete combustion, less particulates in the smoke. Also usually a much larger smoke chamber for the particulates to disperse in.