I know it's an old thread, but full of tasty tech. info for a noob.
I appreciate the technical discussion about smoke formation from burning VOCs. What I'd appreciate more insight on is the conversion from bitter white to sweet blue and how to manage keeping the white to a minimum when maintaining a fire after the food is on.
I'm inferring that the VOCs with the lower evaporation point are also the bitter ones (ammonia and similar) and those with a higher evaporation point are the ones that burn blue - purer hydrocarbons with the aromatic essence of the particular wood. Is that making sense?
My questions ...
Some mention pre-heating smoking woods before adding them to the fire. Does this cause the white smoke producing VOCs to evaporate and go up the stack without being ignited, hence no bitter?
Soaking the wood so it smolders instead of erupts - first, it's clear that not a lot of water really soaks in so this is a way to slow the process. Doesn't this just spread out the same amount of white smoke over time? That this doesn't really reduce white smoke - just makes it less obvious? Or does the steam dissolve and carry away some of the nasties up the chimney without burning?
Tossing chunks and chips in during mid-cook. Isn't the white smoke from doing this unavoidable or does the pre-heating idea make all the smoke produce at once and while the door/lid is open so it vents off quickly without causing harm?
Is there a way to prolong or intensify the blue-smoke phase or is the idea that it only has impact below 140 / for the first hour - put the wood on at the beginning and add the food just when it goes from white to blue - don't bother adding smoke wood for the rest of the low and slow at it has no flavor impact other than soot?
Or is it that the cook chamber is hot enough that the white smoke at the wood level is further incinerated in the air and turns to blue by the time it reaches the grill/food level so no bitterness? Too much new wood at once reduces the air temp. in the chamber so the white to blue conversion can't happen?
To put this in context, the goal is achieving best flavor, not perfect competition smoke rings. Thanks for any thoughts and mentoring! I realize most won't know the chemistry of why certain techniques work, but I'm anxious to learn the subtleties of some of the tricks used to manage the dreaded white. All ideas appreciated.
PS - @ Oldtimer, do you turn up the gas when you add more wood or let the new fuel return the chamber to temp. naturally? <warm smile>
Last edited by Duke; 05-04-2011 at 01:06 PM..
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