In general, the fat cap on a pork butt should be pointed at the heat source as it’s rendered better.
| Type of Smoker | Fat Side Up, Down, or Flipped |
|---|---|
| Offset smoker (standard and reverse flow) | Up |
| Weber Smokey Mountain (WSM) as well as most water smokers | Down |
| Pellet Smoker | Flipped OR Down |
| Weber Kettle | Up |
| Electric Smokers | Down |
| Gas Smokers | Down |
| Gas Grill | Down |
| Drum Smokers | Down |
| Kitchen Oven | Up |
| Crockpot | Down |
Note: This table isn’t all encompassing; I did my best to list the most common smokers and cookers that are used.
Does it Really Matter if the Fat Cap is Up or Down?
After testing all the above over the years – in my opinion – it doesn’t really matter how you put the pork butt on the smoker.
BUT
If you are a person who leaves the fat cap on, I’d suggest putting the fat cap towards the heat source as the fat cap is rendered better.
Pork butt naturally contains tons of intramuscular fat.
This is the biggest reason it’s the best meat to smoke for a beginner; The goal is to pull it so overcooking isn’t super problematic.
For that same reason, the fat cap doesn’t tend to matter much either.
In most cases, all this fat won’t even render and you’re left removing it regardless.
Pork Butt Has a “Faux” Fat Cap and Can Even be Removed
Looking closer at the fat cap you’ll start to notice that there are 3 layers:
- Exterior hard fat (faux fat cap)
- A thin layer of meat (false lean)
- Renderable fat (layer below the false lean)
Here’s me removing this cap:
The exterior hard fat and the thin layer of meat below it are what people call the “false cap.”
If you leave the “faux cap” and carefully remove it after cooking, the “faux lean” is what people call “the bacon” of the pork butt.
Exterior hard fat doesn’t tend to render well nor is it palatable – that’s why people will remove large chunks of fat when they go to pull the meat.
I’d also wager to say people like edible bark more than they like fat.
People who leave the fat cap on will do things like:
- Score/cross-hatch the surface down to the meat. Again though, are they actually hitting the shoulder meat or false cap meat? I’d wager to say the latter.
- Leave the fat cap on and remove it after smoking. This idea results in way less bark if you just removed it from the get-go.
- After smoking they’ll pull the pork and then remove fat that didn’t render.
Also re:”rub penetration” – the only ingredient that will “penetrate” is salt. The rest sits on the surface regardless. This is why you should re-season the pork after pulling.
Food for thought on Increasing “Barky-ness”
In a recent video by Joe Yim, he debones a pork butt and then cuts the pork butt into strips.
The sole intention of doing this is to maximize the bark yield; Or as Joe puts it – “tenderness to barkyness” ratio.
Joe smokes his pork butt on a Loaded Wichita Yoder, offset smoker which features a removable heat plate; In another video he states he doesn’t use that plate.
Even with the heat plate removed – which turns it into a standard flow offset – he opts to put the fat cap down on those strips (the opposite of the advice in this article).
He still turns out meat that looks wonderful.
Like I said, it doesn’t matter much.
Pork Butt Fat Side Functioning as a “Heat Shield” for Hot and Fast Smokers
On Barrel cookers, the fat cap can work to entirely shield the meat from burning.
Here’s a pork butt fat side down on my PBC:
Typically what will happen is the false cap will borderline become charred/inedible but it will quite literally peal off the bottom and the layers below it will be rendered well.
I discard this piece of charred fat and pull everything together.
While this strategy works, it also removes a A LOT of your bark.
