Thursday, May 15, 2008

Aging Sour Beers in Better Bottles

About a week ago a bottled my first sour beer that had been aged in a Better Bottle. It was the Temptation clone that Seth and I brewed back in November. First I'll say the aroma of the uncarbonated beer was outstanding, deliciously funky in that magical Russian River way.

The interesting thing is that the wild yeast and/or bacteria formed tiny little colonies all over the plastic, it was difficult to see when there was beer in there, but once it was emptied it was clear. My assumption is that the microbes are acting just like when they live in the oak of a barrel, scavenging the oxygen as it diffuses in.

I think it is very good sign for the viability of this method, and if the aroma of the beer is any indication this may be one of the best batches I have done so far.

Don't expect a full tasting of this one for a few months, but it is going to be hard to wait too long before I crack one of these open.

19 comments:

DavidP said...

How did the BB clean up? Does it still smell like the original beer?

Josh said...

Oh lord, is that bottle a write off or what?

The Mad Fermentationist (Mike) said...

It actually came right off, the "colonies" weren't imbeded into the plastic, they are just adhered to it. A quick soak in hot water and oxyclean and it looks like new. Anyway, I'm not too worried about it infecting the next beer, because I am going to be using it for a Flanders Red.

Kevin C said...

I thought the Better Bottles were impermeable to oxygen?

The Mad Fermentationist (Mike) said...

The Better Bottle website says "Virtually impermeable to oxygen"

According to Raj Apte ( http://www2.parc.com/emdl/members/apte/GingerBeer.pdf ) the material Better Bottles are made of (PETG) has an oxygen permeability about 1/6 as much as HDPE. A standard 5 gallon HDPE bucket lets in 220 cc/L per year, I assume the Better Bottle will let in about 1/6 of that or 37 cc/L per year. A regular wine barrel lets in about four times less at 8.5 cc/L per year.

I think you can reasonably assume that a barrel may let in a bit more than the math says because as a small headspace develops due to evaporation the wood above it will dry out and become more permeable.

This is all just a back of the envelope scratch calculation to give you an idea of approximately how much oxygen is getting in there. I sent an message to the folks at Better Bottle requesting any oxygen permeability stats they have, hopefully they will get back to me with some hard data.

Kevin C said...

Cool, let us know what they say.

I may have to get one for my beers if that info is correct.

The Mad Fermentationist (Mike) said...

After a series of emails with Walter, Better Bottle Tech guy, I have some interesting things to report. First they believe that the 400 cc-mil/m2-day-Bar Raj gives for PETG is probably for a “extrusion blow material” which is different from what Better Bottles are made from, this is good news as it drags the oxygen permeability down closer to that of a regular barrel (how close I don’t know). They believe that the minimal amount of O2 coming through the plastic is dwarfed by the amount coming from the airlock/stopper which are made of much more permeable materials.

He also shot down my Brett lives on the walls because there is O2 argument. Apparently it is a biofilm, which is just something that some microbes form on wet surfaces when they are in a low nutrient environment (like fermented beer). I have seen this before on infected bottles of beer, but I have never seen it before on a carboy/fermenter.

I still think Better Bottles are a great choice for aging sour beers because it really comes down to the results.

Kevin C said...

very cool.

thanks for the update. i may have to buy one for some of my sour/wild beers

Andrei said...

Did you get a pellicle on your beer? I'm doing the research for my first sour beer, and I'd rather avoid the wooden dowel/chair leg method, so if Better Bottles allow enough oxygen in, that's great.

The Mad Fermentationist (Mike) said...

Some of my sour beers get pellicles, others don't. I actually don't notice much flavor difference between the ones that do and the ones that don't.

I'm still very happy with my results from aging in better bottles and glass carboys with airlocks. I think micro-oxygenation is one of the last issues you need to worry about.

Good luck!

jan said...

Hey Mike,
wondering about your opinion.
Would like to start making around 50l sours up from the 10l I usually made.
The 2 option to use for fermentation are:

54l glass carboys
or 50l commercial kegs

Pricewise they are almost the same. But then I never fermented any beer in a keg. Wonder if it's a good idea for sours.
thanks

The Mad Fermentationist (Mike) said...

I'd worry about moving/breaking such a large carboy. Bullfrog in Pennsylvania did some excellent sours aged in kegs (Kegs Gone Wild). You'll just need to remember to periodically vent the pressure produced by the slow fermentation. Good luck!

Anonymous said...

This same thing has happend with a few of my lambics, and then others It does not. Wonder what the scientific cause is.

CharlieBarley said...

Have you ever tried aging in the Northern Brewer 'Bubbler' plastic carboys? They are on sale 2 for 1. I was wondering if they would work as well as the better bottles as far as letting oxygen in. I believe they are thicker plastic.

The Mad Fermentationist (Mike) said...

We're using similar generic plastic carboys from Austin Homebrew for many of the cultures at Modern Times. I hear the cultures tasted really good, but that was after only a few months of aging. I see no reason they'd present any issues compared to BetterBottles, and the thicker plastic reduces flexing, which limits airlock suck-back.

Unknown said...

Any issues with Better Bottle reacting with higher PH sours over time compared with glass or stainless? How do these compare to the DHPE Speidel plastic fermentors?

The Mad Fermentationist (Mike) said...

Lower pH? Never had any issues with plastic carboys. Haven't used the Speidels for sours yet (no plan to in the short term). In general I'm less concerned about the permeability of the material, and more about the completeness of the seal (which is why I shy away from buckets). The Speidels seem to seal well, so no concerns.

chrissthomas said...

How did they taste? I have two sours going in BB right now at just about a year old. I haven't tasted in a few months but plan to tomorrow. Both developed a nice pelicle

The Mad Fermentationist (Mike) said...

Here are the tasting notes for the Temptation clone. Thanks for digging through the archives!