Cask Strength and Full Proof: What’s the Difference?

In the whiskey enthusiast game, there are a few confusing things.

Sometimes it’s tough to understand the difference between a wheat whiskey and a wheated bourbon, or what sweet mash vs. sour mash is. No doubt in the beginning of your whiskey learning journey, you’ll have these questions. Fortunately we have some answers.

One of those questions happens to be Cask Strength and Full Proof. We’ll even cover the terms that are synonymous too, because believe it or not, that’s another thing to look out for. Let’s break it down.

What is Cask Strength?

In short, Cask Strength refers to a bottle that has not had water added to it. It comes straight from the barrel. So you’re getting exactly the same thing that you’d get if you poured it out of the barrel directly.

Typically these are higher in proof, but they can range really high (even into the 130 or 140 range) or pretty low (close to the 100 proof range). This all depends, because each cask (or barrel) will fluctuate in proof as it ages in a warehouse (also called a Rickhouse). A handful of factors play into the final proof point, including the proof of the new distillate at the time it was barreled, the time it was aged, the location of the warehouse, the general climate and so on.

So why would we drink whiskey like this?

Well, one thing to keep in mind is that whiskey tends to have a lot of character after it’s aged a while. Typically what a distillery will do is to age their barrels and add a certain amount of water to the whiskey that comes from the aged barrel. The reason for doing so is ultimately to get the bottle to a proof point that showcases particular flavor profiles that they like. And trust me, adding water does a lot to change the flavor of the whiskey overall.

Drinking Cask Strength whiskey is an experience in itself; you’re not getting a tweaked product. It’s not going to be perfectly consistent with the next cask strength bottle you get. It’s going to be unique and it’s going to have a lot of flavor. Chances are it’s going to be a bit hot simply because of the higher proof point, but there are plenty of really great notes that come from undiluted whiskey. You may find that more of the seasoned whiskey drinkers are on the prowl for those cask strength expressions. It’s mostly because they’re searching for those deeper notes, and if they’re gonna find them, it’s gonna be in a cask strength bottle.

Synonyms you might see (on bottles) for cask strength: Barrel Proof, Barrel Strength, Straight from the Barrel

What is Full Proof?

Full proof is kind of like Cask Strength’s cousin, in that it’s pretty darn close to it, but not quite the same thing.

Remember when I said that distilleries will add water to the whiskey after it comes out of the barrel? Well, Full Proof is subjected to that process. Water is added, but only enough to take the whiskey down to the proof that it was when it initially entered the barrel. Let me give an example.

A distillery distills some unaged, ‘new make’ whiskey (sometimes called ‘white dog’). This stuff is clear. Let’s say it comes off the still at 114 proof.

The distillery takes that 114 proof new whiskey and puts it into a barrel.

The barrel ages for several years. They take it out of that barrel.

It’s 122.8 proof (remember how we said proof fluctuates in the barrel?). The distillery adds water until the whiskey is proofed back down to 114 proof.

And there you have it: that’s what we call Full Proof. It’s when the whiskey from the barrel is proofed back down to whatever the proof was when it entered the barrel, which is called the entry proof.

Why would they do this? Well, just like standard proofing practice, they do this to attain a certain flavor profile that they think their fans will like.

Alright, so which is better?

That’s the best part about all of this: You get to decide! Also if you get anything that’s cask strength, barrel strength, barrel proof, straight from the barrel or full proof, share with your pal Kevin, would ya?

Cheers, friends! Hope this was helpful.

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