James' method would be one way, wouldn't surprise me if the commercial
process involves spraying water into a series of meshes the smoke had to
travel through though. That method seems to be the only method commonly used
as far as I'm aware to clean exhaust outlets. Most places (including
restaurants) now must do this anyway for environmental (i.e. fats and
odours) reasons. I think they have a small unit where the exhaust passes
through horizontally. There are a series of meshes, in-between which there
are sprayers, effectively creating a complex maze of wet surfaces and
micro-water droplets the exhaust must pass through. Only clean odour-free
air comes out the other side, and the units can be surprisingly small. They
might be looking for clean air, and you might be looking for the smoke, but
the end result would look the same I suspect. They are usually called
exhaust scrubbers, so a search on that might get you some simple ideas to
harvest your own smoke.

Hey, if you collected the output from a restaurant scrubber, could you get
essence of grilled beef or something like that? :-)

All the Best,

Sean


"Bpyboy" > wrote in message
...
> I'd be interested in knowing how they make "liquid smoke" type flavorings.
>
> How do they do it? I have a stand of hickory here (and it does find it's
way
> into the grill) but it would be neat to know how to make something that
gave
> the flavor, maybe on the stove, in bad weather and stuff.
>
> any thoughts?