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Craft Beer Cans vs. Bottles - Is There a Difference?

Author // Jeff Wharton

Years ago, it was revolutionary when Oskar Blues started canning their beers. Recently, though, craft brewers have embraced this packaging format and every year seems to bring more and more good beer in cans. We’re at the point where even Samuel Adams whose founder, Jim Koch, said only recently that they would never can their beer is now putting brew into cans. With the format becoming more popular there’s a contingent of people who say they taste metallic notes in canned beer and those who say you can’t.

I’ve talked to beer packaging experts as well as brewers about this, and their consensus is that cans don’t impart flavor. The lining in cans is a water-based polymer that doesn’t interact with beer. Furthermore, this lining prevents beer from ever touching the metal in the can which, it turns out, is a good thing. The aluminum in modern cans is so thin that, if the lining was to allow beer through, the beer would eat through the metal before you could get it home from the store.

With that said, we thought this was an experiment worth running. So let’s see how it turns out!

Craft Beer Cans versus Bottles

Methodology

We've got four different beers, ranging from a simple craft lager to an IPA. All beers will be poured into an identical glass; we're testing whether cans or bottles effect the actual taste of the beer, not how the presentation effects the perceived taste. The beer will be poured and photographed away from me, so I can’t see which is which (in case there are any noticeable differences after pouring). I will know what beer I’m getting and any information that’s on the bottle/can. They’ll be served to me with a nondescript notation so that I can’t tell based on how the beer is labelled. I’ll get both beers at the same time, side by side, so that I can compare.

Cisco Summer of Lager

Cisco Brewers Summer of Lager

Glass #1

Appearance: Glass #1 has a clear, golden hue to the beer with a thin film of bubbles on top of it. There’s a bit of lacing on the side of the glass as you drink the beer, but not too much.

Smell: There’s a sweet, slightly malty note to this one with just a touch of fruity hops perhaps. That could just be the yeast, though. It’s a little bready, almost like walking into a bakery where a lot of loaves are in the oven.

Taste: Just as it smells, it’s light and mildly sweet. There’s some nice malt to it, but it’s definitely understated. This is one that I could drink a lot of, it finishes with only a hint of aftertaste lingering in the back of your throat and bubbles you can feel scrubbing your tongue.

Glass #2

Appearance: Glass #2 looks the same as Glass #1, except there’s about two fingers of pure white head that is just lingering and lingering. As the beer disappears down my throat, the head does not, coating the sides of the glass the whole way through.

Smell: Glass #2 doesn’t smell quite as sweet as Glass #1. It’s got a brighter, less bready aroma to it and the aroma is much cleaner. It still has a slightly fruity thing going on, again perhaps from the yeast.

Taste: Again, just like the smell, this one is a good bit brighter than Glass #1 and less sweet. The carbonation isn’t quite as strong, but he aftertaste lingers just the same...a drying presence in the back of my throat. Overall Glass #2 leaves my mouth significantly drier, probably from the reduced sweetness. Glass #2 is also a bit more minerally, which is contributing to that increase in perceived brightness.

Which is canned?

Honestly I’m not sure. I don’t pick up any metallic tastes or smells from either one. The differences between the two could be batch variation, as the cans are brewed and packaged at different facility than the bottles...or it could be something else...but none of it strikes me as the metallic notes that are typically thought of as indicative of cans. I’ll pick Glass #2 because it seems a bit fresher and cans allow less air to get in. But, again, I’m just not sure. Neither seems “canny.”

Result - Glass #2 is canned. Jeff is correct.

Wachusett Summer

Wachusett Summer Ale

Glass #1

Appearance: Glass #1 is a light, bright yellow color clear as day. And, just like a bright, clear day there are little wisps of white bubbles on top, just like a few lonely clouds in the sky.

Smell: The smell is clean, almost too clean. There’s a hint of citrus in here...lemon it seems like. Finally, I’m getting a bit of tang at the very end of the smell, but I’m not sure where it’s coming from.

Taste: Again, that lemony fruitness is back. It’s not strong, but it’s there: right up front, then again in the aftertaste. In between, there’s a wheat-like chalkiness. This is a dry, super-crisp beer with fairly strong carbonation.

Glass #2

Appearance: Glass #2 looks exactly like Glass #1.

Smell: If Glass #1 smelled clean, Glass #2 is somehow even cleaner. I’m not picking up much of anything, if I’m being honest. As it warms you’ll find a bit of that lemon from Glass #1, but that’s about it.

Taste: The lemon is slightly stronger in Glass #2 than it was in #1. It’s more persistent of a flavor than it was in Glass #1, but the wheat is still there in the mid-palate. That said, Glass #1 and Glass #2 are really similar.

Which is canned?

I’m even less sure than the last case! At least in that last one there was a difference in sweetness, which can possibly indicate oxygen exposure. I know that these two beers are brewed at the same place, as I’ve seen Wachusett’s canning line. Here it’s just a difference in lemonyness (is that even a word?) which is almost definitely just batch variation. Even if it’s not, I’m not sure what that would mean as far as can vs. glass. I’ll say Glass #1 is canned, as some people think the liners in cans might absorb flavor? But I’m just guessing here.

Result - Glass #2 is canned. Jeff is wrong.

Samuel Adams Boston Lager

Samuel Adams Boston Lager

Glass #1

Appearance: Glass #1 is a robust amber color that is, again, clear enough to read the logo on the glass through. The head is cream-colored and big enough to overflow the glass yet thick enough to not stream down the side. Even halfway through drinking the glass, there is still a ring of foam around the top, sticking to the glass.

Smell: This is definitely a lager, without any yeasty fruitiness in the aroma and that familiar smell that is almost sulfury that seems the be ever-present in lagers. There’s a bit of spicy hops here, but they’re nice and balanced.

Taste: Again, this is definitely a lager. It doesn’t have the yeasty esther notes that even filtered ales have. It’s smooth, with quite mild carbonation and a hoppiness that stays with you throughout the sip, but never overwhelms. The beer isn’t sweet nor is it hoppy. It’s just flavorful, with malt reminiscent of rustic German bread.

Glass #2

Appearance: The color on this beer is identical to Glass #1 (even with the glasses next to eash other), but the head is highly diminished. There’s a bit of lacing around the side, but it’s much thinner than on Glass #1.

Smell: Unlike Glass #1, Glass #2 has much less in this department. The smell is milder, the hops aren’t nearly as strong and the lagery, almost sulfury aroma just isn’t there. Is this the same beer?

Taste: OK...this might be the same beer. The flavor profile is definitely close, but there are different highlights. First, there’s a lot more carbonation here. Glass #1 felt almost like cask ale, but Glass #2 has prickly, sturdy carbonation that hits the roof of your mouth with a pop. The hops are there as well, similar to Glass #1 and that lager taste is definitely back. Aside from the carbonation, these beers identical in taste.

Which is canned?

I have no idea at all! The only difference is carbonation. And that may be just due to the larger head on Glass #1. Even though they were poured together as similarly as possible, maybe one vessel agitated the beer more? I don’t know, I can’t even make a guess here. I have no idea.

Result - Glass #1 is canned. Jeff is wrong as he didn’t even make a guess.

Brooklyn Brewery East India Pale Ale

Brooklyn Brewery East India Pale Ale

Glass #1

Appearance: Again, the beer is clear clear clear with a copper tone to it. A big, off-white head perches on top, just sitting there looking delicious.

Smell: Hops. Yep, that’s pretty much it: a bag of hops. It’s a little fruity smelling, with tropical notes coming through. It smells just like an American IPA.

Taste: And there are still hops here. It’s a little sweeter than I expected from the smell, but not by much. There’s some decent hop bitterness and a resin that sticks through the back of the throat. The malt is pretty light, with hops being the predominant flavor here, but those hops are a little more piney than the smell.

Glass #2

Appearance: Glass #2 is really similar to Glass #1, except there’s only a thin memory of head here and the liquid is a little darker.

Smell: The hops are way milder on the nose in this one. There’s some malt that comes through here, although it’s still in the background and just a hint of mustiness.

Taste: There’s less bitterness in Glass #2. The beer is sweeter, probably because of the lowered bitterness. Also, the flavor of the hops is lighter, which is to be expected since there’s so much less hop aroma. That resiny feeling on the back of the throat is still here, but it’s diminished. And the musty smell I got? It’s here a little bit, but accompanied by a bit of minerality.

Which is canned?

Again, neither beer has any metallic tastes that people seem to associate with cans, but the closest I can come to metallic is the minerality in Glass #2. Sometimes those two flavors can be confused. That said, if cans are supposed to reduce oxygen exposure, the brighter, more fresh hop flavors in Glass #1 would seem to point to that one being the can. So, basically, my decision comes down to whether I think the mineraly/metallic flavors or the brighter hop flavors come from the can. Given what I know about the polymer can linings, I’m going to guess that the increased hop flavor and freshness is from the can.

Result - Glass #1 is canned. Jeff is correct.

Conclusions

I ended up getting half correct and half wrong...although I couldn’t even make a guess on one of the beers. 50/50 is what you’d expect if I was just guessing, so it seems that I couldn’t tell which was which. I didn’t pick up any metallic flavors in any of the beers that weren’t there across both glasses. After knowing the results, it seems that cans gave beer more head, possibly because you have to pour over a raised lip which agitated the beer, as opposed to a smooth glass bottle top? Either way, I couldn’t find any of the alleged flavors that people claim to get from cans. There were definitely flavor variations between the bottles and cans, but that could be chalked up to batch variation, differences resulting from contracting the beer out to facilities with a canning line or other reasons.

We’d love to hear from our readers, though. What do you think? Do you notice metallic flavors when you drink beers that have been canned? Let us know.