OT. Craft Beer issue

[J Tiers]

That graph has a linear vertical axis, which means it offers no useful information once the transmission of the glass falls below a few percent. Brown glass certainly transmits less UV than clear glass, but it does not block it entirely. Hence my statement "Even with brown bottles, skunking can occur."

Yes, I expect it might, eventually, especially if compared to a can.

You did, however, add the qualifier "very quickly" to your original statement. One would suppose that cutting the transmission at least 20:1 (and probably considerably better) would modify that "very quickly" compared to a clear glass bottle such as Corona or some others. Or a green glass, such as Molson and Heinekin use..

The term "very quickly" is open to many interpretations..... One might consider that a 60 second exposure as the crates are rolled in on a two-wheeler dolly might qualify as "very quickly". By that standard, the clear bottle beer should be rendered undrinkable by that exposure if brown bottles allow detectable skunking. So that is outside the lower limit of "very quickly", one would presume.

So it might be as well to define your "very quickly", and compare that to normal shipping practices, to assess the "skunking risk" of clear vs green, vs brown bottles, all of which are in daily use.

[tomato coupe]

So it might be as well to define your "very quickly", and compare that to normal shipping practices, to assess the "skunking risk" of clear vs green, vs brown bottles, all of which are in daily use.

What I've been told by a local brewery owner is that it can occur in a matter of minutes, which I interpret as being a worst case scenario.

[J Tiers]

What I've been told by a local brewery owner is that it can occur in a matter of minutes, which I interpret as being a worst case scenario.

One has to wonder if that is equal with clear , green and brown (amber) bottles. Considering the difference in transmission between them, it would seem unlikely to be equal.

A statement that it "can" happen in a few minutes, but specifying no conditions, is a totally "uncalibrated" data point that can be given very little weight. We do not know if he referred to beer in a glass, directly exposed, or in a bottle, and have no information as to what sort of bottle if so. There is essentially no new data in that, since we all agree that UVA can cause skunked beer under some unspecified time and conditions.

As for the linear scale, there is an absorption chart given in the link, which you probably did not see. The percent absorption for brown glass varies from a stated 100% to 96% depending on wavelength in the range from 325 nm to 500 or so nm, which covers the applicable UV range.

Interestingly, the brown glass is there stated to be expensive and hard to get, where other sources say it is cheap and available. Given that the "standard" US beer bottle is brown, it presumably cannot be "that" expensive and hard to get.

[tomato coupe]

One has to wonder if that is equal with clear , green and brown (amber) bottles.

Brown.

A statement that it "can" happen in a few minutes, but specifying no conditions, is a totally "uncalibrated" data point that can be given very little weight. We do not know if he referred to beer in a glass, directly exposed, or in a bottle, and have no information as to what sort of bottle if so. There is essentially no new data in that, since we all agree that UVA can cause skunked beer under some unspecified time and conditions.

Then you should ignore it -- it won't offend me one bit.

As for the linear scale, there is an absorption chart given in the link, which you probably did not see. The percent absorption for brown glass varies from a stated 100% to 96% depending on wavelength in the range from 325 nm to 500 or so nm, which covers the applicable UV range.

Been there, done that. See my post #45.

[JRouche]

Again. You folks are bat chit crazy (its a thing).

You went way off schedule me thinks.

5 Gallon Cornelius kegs were the standard.

I have fresh rebuild O rings and vent stuff after every run.

I run a pretty clean environment when brewing.

Try to make a 3 gallon batch. You might like it. There are kits everywhere. Prolly use the syrup. It will make great beer. The hops and yeast is where the flavor comes from, along with other post boil stuffs. The syrup is the sugar.

Ahh, we have a local brewer (big scale) and you can get a SS growler but that doesn't work for me. Gets stale.

Nice SS Thermos. JR

[754]

Too much air in a can or bottle is the enemy of beer if it sits for a while..
the most remarkable thing I have seen in the beer world in decades is the bottom fill cup they use in stadiums and maybe bars, simply amazing.
look up bottom filling beer cup on youtube..

[RMinMN]

As most do not keep their beer out on the patio in the sun, the bottles for most better brands are not clear, and that even clear glass is not transparent to UVB, that seems less important. The bottles are normally a reddish brown, which should be better at blocking, although I do not know the attenuation curves for "standard brownish glass".

The brownish glass is apparently the cheapest type, as well.

There is evidence that beer kept in a commercial cooler with florescent lights can skunk if in clear glass. No notation on how long it might take as the amount of UV put out by the florescent lights must be pretty small. People have mentioned that beer poured into a clear glass will skunk pretty quickly if in direct sunlight, fast enough that it is noticeable before their glass is empty.

[RMinMN]

Agree. but of course heat can be associated with exposure to sunlight, so there can be a connection.

Wine that is not "killed" somehow is susceptible to "going off" toward a vinegar flavor if the wrong form of yeast is in the bottles, and heat may make that happen faster. Some similar effect may occur in beer. When I made wine, there was an additive to stop the "bad bugs", but of course I was not making fine wine, just trying for the possible equivalent of ordinary bistro wine.

The vinegar is caused by a bacteria, not yeast. The bacteria is acetobacter and the usual cause in beer is moving the beer from the primary fermenter that has a sealed lid with an airlock that keeps CO2 in and air out. When the beer is moved the CO2 is lost and replaced with air. If that air has acetobacter that bacteria can propagate in the beer as it requires some oxygen to propagate. The accepted solution if moving to secondary is to use a glass carboy and fill it all the way to the neck and put an airlock on it. The CO2 dissolved in the beer will then fill this small space but there won't be enough to fill the bigger opening fast enough to keep the acetobacter from propagating.

[J Tiers]

I expect you are correct. I have not done winemaking for many years and was not recalling the nature of the "vinegar bug" correctly. In any case, it can "go off" if precautions are not taken.

Makes you wonder how they ever got good wine or beer centuries ago before the nature of the problem was understood. Just another of the closely held "secrets of the trade", presumably..

..... as the amount of UV put out by the florescent lights must be pretty small. ........

Must be, or we'd be hearing about the skin cancer risk of fluorescent lights.... I have not heard anything about that, which does not mean there is no risk. But people do spend all day in the office under fluorescents, and at the end of the winter, they do not have a tan..... in fact if they did in the fall, they probably lost it by spring.

The lights DO work by making UV, and having that energy excite the phosphors coating the glass, which then "fluoresce" providing the light. So one might expect that there would not be 100% blockage of the original UV, some would get through.

I assume the coolers referenced must be of the type where "you close the door and the light STAYS ON!".

[MaxHeadRoom]

My home brewed stock inventory generally averages about 12 milk crates total , Each of which holds exactly 16 Grolsch bottles.
They are kept in a darkened basement so no chance of UV light contamination etc.😉
For wine, I use the pure crushed grape juice. A 25Litre brew at a time.
Max.
.

[Mcgyver]

I find Heineken is often 'skunked', green bottle obviously. We might have different sensitivities to it, I recall i've often complained about it whereas others thought it was fine. I didn't know it was a UV thing....but really, how much UV exposure does beer get?

Its been tough on us Canuks....the bloody country's been going downhill since the disappearance of the brown stubby

[MaxHeadRoom]

For some odd reason, Grolsch switched from brown bottles to green quite a few decades ago?
I would be intrigued to find out how they flip the bottles closed on the bottling line!😎
Max.

[Tom S]

Let's just settle this once and for all and say that the best beers in the world come from Belgium in a bottle with a cork and cage, and if a bottle is good enough for a trappist brewery it's more than good enough for me.

[J Tiers]

I find Heineken is often 'skunked', green bottle obviously. We might have different sensitivities to it, I recall i've often complained about it whereas others thought it was fine. I didn't know it was a UV thing....but really, how much UV exposure does beer get?
.....

Agree on the UV exposure. Where does it get so much? I never see anyone leave the bottles out in the sun during shipping/delivery.

Maybe the flourescents can do it, the green bottle is not a good filter. I don't know, I am not particularly fond of Heineken to begin with. Nor Molson, which is/was also green bottles.

But Anheuser products are all in brown (or clear) bottles and I think most are brewed skunky. I can't blame it on bottles when it tastes just as bad from a keg.. The horsepiss is brewed right in town, but that's what most all of it is, IMO.

Let's just settle this once and for all and say that the best beers in the world come from Belgium in a bottle with a cork and cage, and if a bottle is good enough for a trappist brewery it's more than good enough for me.

Without arguing, I will just say that ALL the beers and ales that I like the best (aside from local brews in Germany) come in bottles. Belgian beers are among them.

[gmax137]

When I was in high school I drank mostly Miller beer - the original "champagne of beers" in the clear bottle. The someone told me, Miller had to add formaldehyde to the beer to keep it from going bad in the clear glass. Probably nonsense, but I stopped drinking that stuff and moved on to the good stuff. You know, like Schlitz malt liquor. Actually I think the growth of the small breweries as one of the few things that have improved over the past decades.