Science Of Smoke Question, Please...

[NorCalQ]

I've read on many sites that pellet smokers, although burning very efficiently, impart a much milder smoke flavor than wood or coal plus chunk burners. Some pellet smokers create plenty of smoke, but produce a much weaker smoke flavor.
What really is the difference between pellet smoke and chunk or natural wood smoke that would create the difference? Even though many say wood is wood, pellet or not, there's got to be a difference to create such different results. I know everyone has their opinions, but I want to hear the real science, if anyone knows.

 

[RickB]

I've read on many sites that pellet smokers, although burning very efficiently, impart a much milder smoke flavor than wood or coal plus chunk burners. Some pellet smokers create plenty of smoke, but produce a much weaker smoke flavor.
What really is the difference between pellet smoke and chunk or natural wood smoke that would create the difference? Even though many say wood is wood, pellet or not, there's got to be a difference to create such different results. I know everyone has their opinions, but I want to hear the real science, if anyone knows.

Im sure there are many people on this forum wiser than i on this subject but my guess is as follows. Most of the pellets i use are only 30% flavor wood. Wood chunks are 100%. But here lies the rub...if your using wood chips there is no way your going to get the constant smoke your getting from pellets on long cooks. Pure wood charcoal is expensive for long cooks and not easy to control the temp for long cooks, at least for the backyard cooker. All in all I dont see a big difference in taste. But i do see a huge difference in ease of cooks. Fill the hopper set the pellet boss and relax. Easy smoking!

Ps..mild flavor? You want to taste the wood...or the meat. The wood should compliment the taste of the meat not the other way around.

 

[NorCalQ]

I'm not saying whether or not I want or don't want more smoke flavor. What I do want is to know the science behind the two different types of smoke, if indeed they are different and why they impart different smoke flavor to meat?

 

[Big Poppa]

I dont know the science but do know that the convection fan has something to do with it....sticks give a very much stronger flavor profile charcoal with chucks ditto

 

[NorCalQ]

I guess I know what the results are, but I'm really curious about the science behind it...not that I'd understand it all, but I'd still like to know.

 

[HoDeDo]

BP is hitting on it... How cleanly your wood is burning plays HUGELY into your smoke profile... Think about the cookers you see with a lot of grey, or a chuggy smoke. The meat coming off of them can many times have a bitter aftertaste. That is the wood not burning completely... and the same characteristics that burn your eyes when you open your pit, also give you a heavy smoke flavor, that also eventually gets bitter.

The cleaner the burn, the lighter the smoke profile and the more complementary the flavor, vs. the smoke taking center stage.

Some folks strive to burn an ultra clean fire... so they build a good coal base, and burn small amounts of wood at a time; it requires more maintenance, but puts out the best flavor.

Pellet smokers are the epitome of this - They are a very efficient fuel source (compressed sawdust), and you couple that with a precision delivery system, and forced air to burn them... and you have what most would say is a near perfect smoke.

Think about wine and "cooking" wine... If you wouldnt drink it, you darn sure dont want to cook with it. Same for smoking, if it is burning your eyes, you need to tend your fire... The pellet cookers take care of that for you; always a clean efficient burn.

From there, you just take on the characteristics of the wood being used. Peppery, Sweet, Nutty, Spicy, Earthy, etc. And the color...

 

[Big Poppa]

Very nice Andy

 

[TentHunter]

Bingo!!!! Andy summed that up perfectly.

I think the first rookie mistake most people make when getting into smoking meats is thinking that you have to a white billowing smoke that leaves a heavy smoke flavor, which means you'll be burping smoke rings after eating food smoked that way - YUCK!!! That taste stays with you for hours!

In fact, I think that's why so many people I meet say, "I don't care fore smoked foods." I also think some folks have simply gotten used to that heavy smoke taste and when the pellet smokers don't give that, than they think something is wrong.

I don't get a radically different flavor smoking with charcoal/wood chunks versus my Pellet smokers. Why? Because I learned years ago to control charcoal or wood fire temps by controlling how much fuel was used and NOT by choking the oxygen off to the point that it started burning dirty. A clean burn with enough oxygen = a clean lighter blueish smoke which flavors food instead of overwhelming it.


I love BP's analogy, "Think of smoke as a spice." OK, think about that... you don't want any one spice totally taking over a food's flavor. You might as well just dump a bottle of that spice in your mouth. It's the same way with smoke.

Pellet smokers put out that coveted light blueish smoke without effort. I love it!

 

[NorCalQ]

Thanks for the replies. I really hope someone here has some science of smoke knowledge. I'd love to know what happens on a molecular level to pellet smoke as opposed to other types of smoke.

 

[TentHunter]

Maybe this is more what you're looking for. Like Andy (HoDeDo) said It's all in how cleanly & hot the wood is burning, not whether its a pellet cooker or charcoal.

As wood starts to burn it releases nitrogen & volatile hydrocarbons (including creosote). The hydrocarbons are what you see as smoke. As the temperature increases these hydrocarbons burst into flames and are quickly converted to other substances including Carbon Dioxide.

Oxygen is the catalyst for this process. More oxygen = the faster this conversion take place producing less smoke and releasing more heat energy. Less Oxygen = lower temps and more smoke.

Water also acts as an inhibitor to this process, which is why soaked wood chips placed on top of charcoal do not burn cleanly and produce a lot of heavy smoke.


Ergo, a larger charcoal fire that is being starved of oxygen to control the temp will release more unconverted hydrocarbons; in other words, more smoke.

Pellet Smokers have a constant flow of air being forced into the firepot, much like billows in a forge. This allows a very small fire to burn very hot and produce a much cleaner smoke with less creosote & hydrocarbons being deposited on food.

So it's not the pellets per se, but rather how efficiently they are burned that makes the difference.

 

[NorCalQ]

Maybe this is more what you're looking for. Like Andy (HoDeDo) said It's all in how cleanly & hot the wood is burning, not whether its a pellet cooker or charcoal.

As wood starts to burn it releases nitrogen & volatile hydrocarbons (including creosote). The hydrocarbons are what you see as smoke. As the temperature increases these hydrocarbons burst into flames and are quickly converted to other substances including Carbon Dioxide.

Oxygen is the catalyst for this process. More oxygen = the faster this conversion take place producing less smoke and releasing more heat energy. Less Oxygen = lower temps and more smoke.

Water also acts as an inhibitor to this process, which is why soaked wood chips placed on top of charcoal do not burn cleanly and produce a lot of heavy smoke.


Ergo, a larger charcoal fire that is being starved of oxygen to control the temp will release more unconverted hydrocarbons; in other words, more smoke.

Pellet Smokers have a constant flow of air being forced into the firepot, much like billows in a forge. This allows a very small fire to burn very hot and produce a much cleaner smoke with less creosote & hydrocarbons being deposited on food.

So it's not the pellets per se, but rather how efficiently they are burned that makes the difference.

This is great...this is what I'm looking for. So, what chemical/substance is it that deposits on the meat to give it the "smoke" flavor?