Cans v. Bottles

I wouldn't want to age beers in cans. I know glass won't give me anything nasty...but put liquid on a can liner (or whatever else is in there) for a few years...no thanks...

There's much, much, much more that goes into aging alcohol than just oxygen. Ask the wine guys.

 

There was a big step in freshness on a Bigfoot vertical when we hit the 2008, which is when they went from twist off to pry off caps.

Beers packaged with minimum O2 will still have oxidation due to redox reactions.

 

Bottles have cap liners. The thread I referenced above has reliable folks from places like Victory and In-Bev saying they aren't sure if the greater surface area but lesser thickness of can liners is better / worse for beer than the smaller surface area and greater thickness of the cap liner. So this seems like a point of faith, not fact.

I'd like to actually know what the aging benefits are that are not aerobic. What is this much, much more? And would they be the same for beer as wine? That second point doesn't seem at all clear.

Again, if we assume the cap liner versus can liner is equivalent then a well sealed can would be better than a bottle if oxygen-less processes contribute to aging.

 

You have posted some good questions of:

· “I'd like to actually know what the aging benefits are that are not aerobic.”

· “…if oxygen-less processes contribute to aging”

As regards the aging of certain beer styles and the maturation of flavors during aging, the flavor maturation that I am personally familiar with are flavors from oxidation. For example, lots of folks like the sherry like flavors that a maturing Barleywine achieves. One other example is the dark fruit flavors that a maturing Quad/BSDA achieves with time in the bottle. The sherry and dark fruit flavors are from an oxidation process.

As Jeff (@hopfenunmaltz) already mentioned, there will be some oxidative maturation in canned beers since some oxygen is introduced during the canning process. Needless to say but additional oxygen does not ingress into the can over time like occurs with bottled beer (since the cap liners are not oxygen impermeable).

Maybe @Peter_Wolfe can provide additional input on what flavors are achieved through non-oxidation processes with aging of packaged beers.

Cheers!

 

You don't need O2 to have oxidation. There are oxidation-reduction reaction that take place, that will change a beer. Google "redox reactions".

 

Well, since there have been a number of technical posts…

There is an excellent technical article entitled “The Chemistry of Beer Aging – a critical review”: http://www.sciencedirect.com/science/article/pii/S0308814605000865

In paragraph 4.9 Oxidative vs. non-oxidative beer aging it states:

“From the previous considerations, it becomes clear that oxygen triggers the release of free radicals, which can easily react with many beer constituents, leading to rapid changes in the flavour profile. Among these processes are the oxidation of alcohols, hop bitter compounds, and polyphenols. … Modern filling equipment can achieve total oxygen levels in the bottle of less than 0.1mg/L. At such low oxygen levels, it is debatable whether the formation of ROS is the determining factor in the aging of these beers. Indeed, other molecules present in beer have enough reactivity to interact and form staling compounds. Beer staling is often regarded as only result of oxidation, but non-oxidative processes may be just as important, especially at the low oxygen levels reached in modern breweries.

Non-oxidative reactions causing flavor deterioration are esterifications, etherifications, Maillard reactions, glycoside and ester hydrolysis. Even (E)-2-nonenal, a compound long suspected to be the main cause of oxidized flavour, paradoxically appears to arise by non-oxidative mechanisms in beer. This explains why staling is possible in the absence of oxygen. On the other hand, although some compounds result from oxidation reactions, it is at present not really clear with compound(s) is/are responsible for the oxidation off-flavour of beer.”

A few comments to the above extracted text:

The text above discusses the amount of oxygen during the bottling process (e.g., “Modern filling equipment can achieve total oxygen levels in the bottle of less than 0.1mg/L.”). It is critical to remember that for bottled beer the amount of oxygen in the bottle is not solely from the oxygen introduced during the bottling process but the continued introduction of oxygen via ingress through the cap liners (since the cap liners are oxygen permeable).

Now, let’s discuss the non-oxidative reactions mentioned above. The paragraph above discusses this from the perspective of “flavor deterioration” and “staling” so it is indeed true that non-positive flavor changes can occur over time via non-oxidative reactions. What I don’t know is whether there are any positive flavor changes via non-oxidative reactions. In other words, are there flavors akin to sherry flavors or dark fruit flavors that are achieved via non-oxidative reactions?

Hopefully @Peter_Wolfe will chime in on this discussion topic.

Cheers!

 

THink of the can as a mini keg ... and i perfer my beers on draft

 

Aesthetically speaking, bottles are always better. However, cans are really nice, because they're easier to transport and dispose of, and you don't need a bottle opener. Personally, I like both options. I wish Stone would release their beers in cans, especially the Go To IPA.

 

While I don't have a source, my intuition as an engineer is that whatever reactions take place are primarily a function of surface area. Thickness shouldn't really play a part, unless the exposed surface is consumed during a reaction, at which case thickness would matter. You could then compare the volume of compound in a cap liner versus can liner...but the can liner would certainly have a faster reaction due to surface area.

So I don't agree with your last assumption.

 

Yeah, I don't think we know the answer. But my point that both are exposed to this liner material and cans are potentially lower oxygen environments, particularly with prolonged aging, remains true. And if the reaction is just slower but potentially the same with a capped bottle, then that's a strike against bottle aging.

I guess I'd appeal to the engineer in you and hope you now agree that aging in a bottle versus a can isn't as clear cut as it may have initially looked!

 

I am not huge on beer knowledge so I am not considering myself as all knowing beer guy. But I had only heard that bottles could be good but sunlight could damage them and also that when bottling, the temperature of the beer is really warm so that it will not produce so much carbonation when filling. Also I've heard that cans are not very good either because if its in a can its cheaper or not as good. but honestly i would say it just depends because I have definitely had beers where can was better or bottle was better. I Dont know, just some thoughts.

 

More and more beers available in cans now through mobile canning like Iron Heart and breweries buying canning lines or single head can fillers here in MA.

There are pros and cons with cans and bottles, but a lot more places are going with cans due to packaging and space preference with retailers and restaurants. Hit or miss, but cans seem the way to go.

 

Bottles and cans both have it's pros and cons. That's the why I see it. That being said, I have always liked it when breweries do a mixture of both.

 

I really don't think it matters. There's some good wine that comes in screwtop bottles vs cork.

If the contents suck it doesn't matter what holds it. Would HT taste better in bottles or cans? Right. Stupid question.

Cans are easier, stay cold longer, easy to transport. Plus who drinks craft beer out of a bottle? It's usually poured in a glass anyway. To me there's nothing better than a nice cold tallboy of a DIPA.

 

Can or bottle - if the beer is good the beer is good regardless of the container.

I'm personally on the can bandwagon now - they're better for the environment, no problems with light struck beers, and they're cheaper so the beer should (theoretically!) cost less.

 

I choose glass because I prefer not to ingest BPA and whatever else is in the can lining. I recommend everyone learn about the nasty effects of BPA and other endocrine disruptors and synthetic xenoestrogens. Environmental working group is a good source.

 

Supplication in a can. I'm in.

 

Luckily, unless you store your beer above 90 degrees or so there is little to no leaching of BPA in cans... well, no more than what happens with the crown liners in bottles. So unless you prefer drinking hot beer, the amount of BPA leached is pretty much negligible, unless you're going to down a case per day (in which case you'll experience a host of other problems before you would have to worry about being poisoned by BPA). Even during pasteurization cans are not subjected to that high level of heat for more than ten minutes or so, which is not significant enough to raise that leached BPA to disconcerting levels.

BPA is dangerous, but not in the levels present in canned beer. Aside from BPA, can liners are pretty nonreactive with acidic liquids, so there is nothing else to ingest.

 

I cant stand canned beer. I keep telling myself that I love draft beer and it comes out of an aluminum keg, so the aluminum cant be making the beer taste weird but theres just something about cans. Its probably all mental on my part but its something Ive never been able to get past.

 

These days just about all kegs are Stainless Steel Sanke kegs.