I learned a lesson... the kind that only comes with experience and dabbling instead of academic... I'll share it with y'all, but I don't expect it to be accepted until you've experienced it for yourselves.
so... smoked a whole sirloin last weekend. It turned out better than anything I've ever smoked. The bark was perfection and the ring was apparent and uniform and to a depth of perhaps an eighth of an inch. The wood used was an oak/maple mix of my own blend. The sirloin was rubbed well with coarse salt and black pepper, and some of that montreal steak seasoning. nothing special. i took the 11# cut up to 112* internal, and then wrapped it in foil, then a towel, and then a cooler for another hour. The smoker rendered a medium rare masterpiece of 'sweet' smoked heaven. not a bit bitter. it's the first time i've ever successfully smoked without a hint of 'bitter'... here is the lesson learned.
BLUF (bottom line up front) : It's ALL about the fuel. Without getting into the chemistry specifics which i have little grasp of understanding, wood is chock full of naturally occurring chemicals. These impart the bitter taste, and they often cause wafts of thick white to light gray smoke. This is bad. Many counter this by smoking 'full smoke' only partial cook time, and attempt to bypass the smoke during later phases. Many 'soak' wood chips to smoke. This is wrong. The way to dispense with the bitter flavors is simple: only burn natural wood fires that have been rendered to charcoal. there is little smoke, there is zero need to 'soak' chips, and the chemicals that impart the bitterness are long gone before you even drop the match at cook time.
my set up is a wood fired ecoque gen2 smoker/pizza oven. It's made everything from brisket to applewood smoked bacon, to breads and homemade pizzas. it works great and i am happy with the purchase. there is no gas involved, and there is no 'briquettes' to be used.... you only want to use clean and natural fuels, and always as dried out (seasoned) as possible fuel... and that's what i've been doing. no matter how seasoned, though, the smoke stack never lies- the smoke coming out of that thing can be described, at times, as clouds- white, pillow like, thick and consistent. this is a bad thing.
I was reading a study offered up by aTm (if you can believe it) about how 'types of woods aren't as important as origin of woods'... i found this interesting to say the least. the basic premise is "Oak from one location geographically may be better suited than Hickory from another or vice versa, and it may be better than apple or any of the fruit woods depending on it's geographic origin."... they went as far as to say "hickory from some places properly seasoned imparts a sweeter flavor than, say, cherry from another"... here is the key though, and it was strongly stressed: "It really doesn't matter what wood- so long as it is a hardwood- as people talk a lot about the subject the truth of the matter is they can't truly distinguish one way or the other what wood was used, but they can absolutely tell if that wood wasn't properly prepared prior to being used in the smoker".
for this evolution planned for the Sirloin described above, the plan was to use solely charcoaled lump with only spits of 'fresh' silver maple the size of pencils or so, and to NOT add any more 'fresh' wood after the start. the smoke was not apparent at all throughout the cooking process- it could be smelled, but even ten feet away from the stack it was barely visible. Opening the chamber a few times during cooking usually results in vision clouding breath holding efforts to 'wait it out' before you can inspect progress- but not this time. there was certainly trapped smoke, but it was there and gone as soon as the chamber was accessed. ... I had my doubts about this based on what i was seeing, but i figured it prudent to not change gears mid race.
as mentioned, the results are perhaps the best smoked red meat i've ever had from any location at any time... I'm not trying to brag, as all i really do is observe the process anyway, i'm just saying straight up that patience and using the right material makes all the difference in the world. not a little difference. a massive huge gigantic difference. one that makes you think it's time to hang that 'smoke master' sign above your pit. that, of course, won't happen- but there was much fanfare over that sirloin and people not only familiar with smoked meats but my efforts in the arena that were as stunned as i was over how good it turned out. Lump
charcoal only. next time, I even think i'm going to abandon the sprigs of silver maple, to be honest.
the irreplaceable keys to all of this: Don't trust store purchased lump charcoal. Don't expect to find something near as natural and prepared as what you can do for yourself.
Starting with a metal barrel, preferably a metal trash can no bigger than 20 gallons or so (you can use a drum, but where has that drum been and what was it used to store?) remove the lid and cut six or so 3" holes around the perimeter- revolver style. Place a couple fire bricks under either side of the barrel in the fire pit (not the smoke pit- a bonfire type pit) to keep it a foot or so off the ground, and build a stack of limbs of whatever sort, split wood, whatever all around and under the barrel/can. fill the can with your smoking wood cut in no longer/thicker than 6" chunks, and fill the can 3/4 full. secure lid. ignite the fire pit. keep it fed and burning strong. at around 700* the wood in that can will start to off gas flammable gas- and this is fun: ignite it- it will burn like a torch until it's gone long gone. Let the fire roar with the torch looking fire burning atop the can until it dies completely- which is at least 24 hours...
after the fire is absolutely dead, pull your can out and dump the contents into a bin for storage. you now have absolutely clean and prepared all natural charcoal lump to cook with.
it's easy to ignite in the smoke pit's cooker (you'd think it infused like a briquette it's so easy to light) and it burns exceptionally clean. It will burn hotter and not for as long- but since it's natural and free of any type of chemical, but you can always add more to the fire as it will burn without any ill impacts...
it doesn't matter so much the type of wood you use- oak, hickory, maple, apple, cherry, mesquite- as we've been told for years and years. what matters is the origin of the wood (if you subscribe to aTm's study) and CERTAINLY the 'state' (condition) it's in when you fire it. for the love of all that's holy, you've gotta try this.
note on wood chips popularly sold in bags: the common thought is to soak these. this is wrong. you don't want anything to do with what's in that smoke when it comes to food... it is a certain way to get that bitter flavor. you also don't want to burn them dry- because it is rarely seasoned to the proper expectation. it will burn with clouds of white smoke. you don't want to set them on indirect heat with intent to 'cook' the flavors out of them... that's another way to get those chemicals on your food that render bitter. you can either stay completely away from them, or run a mini-kiln out of them making them charcoal just like described above. otherwise, these are basically a waste of money and/or effort.
I'll never smoke another way, and I can't wait to use this method on a massive brisket i've got staged right now, and on a piggy i'm getting as soon as the farmer down the road harvest them (should be a few weeks) as I'm looking forward to that sweet smoky flavor recently discovered on a pork belly turned into bacon goodness.
i hope this is at least tried by someone here, so you can experience it for yourselves. it is the only way to do it, i'm thinking. i'm also thinking after you've done it you'll agree...