Barrel-Aging Brewers...please read! Lactobacillus traced to barrels?!?

[tsmack]

Fellow barrel-aging brewers,

I've been occasionally barrel aging (4-16 barrels/year) in freshly-emptied bourbon barrels for 13 years now and have left beer in them for as little as 3 weeks and as long as 10 months and haven't experienced any problems packaged or draft with the finished product. Our new production brewery has a much larger barrel aging program and we are experiencing random lactobacillus contaminations (causing batch losses) that we are rigorously tracking with HLP and LMDA/SDA media testing. It seems, to my great surprise, that--sporadically--batches are clean in the FV but contaminated by the time they are ready to leave the barrel, leading us to the obvious conclusion that the barrels are harboring these bacteria.

We do nothing to the inside of the barrels; we do power wash the outsides with a water/Starsan blast two days in a row before filling, in order to seal the barrels. The barrels are aged in 62F room with airlocks. I've always operated under the assumption that these barrels are very sterile because they were last filled with 120-130 proof bourbon. We order half truckloads of barrels (144) and they sit around much longer than I had previously ever stored barrels; this is the only new variable in our process.

For those of you with barrel programs that are packaging and concerned with extreme shelf stability, what are you doing to your barrels? We've literally had batches that will pass an HLP media test with 0 lactobacillus colonies after 5 days, and batches that will show 100+ colonies after 5 days, all other factors being equal. It is blowing my mind. I'd love to start a conversation on this with any of my barrel-aging brethren!

Thanks,

Taylor Smack
Blue Mountain Brewery
Blue Mountain Barrel House

[brewmaster 2011]

What is the IBU of the beers that pass and ones that don't pass.

[tsmack]

ibus

Contaminated batches as high as 70 and no lower than 26. But, correct me if I'm wrong, the antiseptic qualities of hops do not affect lactobacillus.

[jwalts]

Some lactobacillus strains are sensitive to hop compounds, and (as far as I know) all strains are somewhat alcohol- and pH-sensitive. Is it possible that the lactobacillus is coming from the room itself and not your beers, or are you throwing out batches because they're sour? Is it possible that you're growing pediococcus on your media?

Joe
Ale Asylum
Madison, WI

[DageraadBen]

Are the barrels possibly being exposed to malt dust during their extended storage period?

[tsmack]

all good ideas, but...

Contamination positively identified as a lactobacillus, not a pedio. Barrels stored in a sealed 62F room.

Grain room is very separate with a good suction fan. It is left open sometimes during grain-in for brews (and we're going to be ever-so-careful about that now, obviously), but that would have to be entering the barrels during filling, and we rigorously and continuously purge barrels with CO2 during filling from FVs.

Thanks for the ideas...keep 'em coming. At this point we're looking into steam-blasting the barrels as a solution.

Taylor

[Geoff Logan]

Have you considered temporarily switching to a different source for your barrels? Maybe your broker isn't treating the barrels as well as they say they are. I'm assuming that you're not picking them up yourself anymore. It's never boring, is it?!

As a side note: In the past I've received brand new LMDA plates that were pre-contaminated. They would grow bacteria before we ever took them out of the sealed package! Anyway, best of luck Taylor.

Geoff

[Oregone]

How long are you storing the barrels empty prior to use? Perhaps they're losing enough alcohol from the wood that you're creating a more hospitable environment for the bugs, and an easier transfer into the product?
Also agree on the supplier potentially being a culprit. Are they 'wet' with liquor still when they arrive? When they're filled? I've heard of doing a thorough 'wash' with bourbon to saturate the interior prior to filling for barrels that have sat. Sanitary, and has the benefit of not stripping the character that you're looking for. Plus you could reuse it.

Edit: I see you're thinking of steaming them. Also a potential solution. I'd still think of doing the wash after.

[brewmaster 2011]

Remember that Pediococcus is in the Lactobacillus family. Are you detecting any VDKs in the infected Barrel Beer vs out of the fermenter.

[BrewinLou]

How about the barrels picking up malt dust at the distillery where they are being emptied?

[tsmack]

good thoughts...more responses

Unless my supplier is just hugely lying to me, they don't seem a culprit--the last time I got barrels we were in contact hour by hour waiting for the next shipment of barrels to arrive from the distilleries to the cooperage and right off to me. Always seem very wet and strong with bourbon, and I've been using these guys for 8-9 years now.

But, before this last shipment, we did have some barrels sitting on pallets, wrapped with pallet wrap (but not at all sealed) on top of 20' racks in our temp controlled brewery for 3-4 months...not that long, but still caught some summertime heat increase despite our temp control.

As for pedio and lacto being in the same family (lactic acid producers), the lacto was positively identified by morphology, and--to beat a dead horse--staining. It's lacto. I outsource my QC to a local lab that is crazy-advanced...always triple-plate everything (with controls), autoclave our sample bottles, sterile hood, the whole 9 yards plus another 9. We do a lot of other non-barrel-aged beers. All totally clean. All beers (barrel-aged and non-barrel aged) share the same hoses, FVs, cross-pitched yeast strains, brites, bottling equipment. Literally everything is the same and then BAM! sporadic batches of the barrel-aged are lacto-ridden.

Ordering a steam-generator and special wand today. Reeeally expensive, but so is losing a few batches of beer.

[nateo]

This might be a stupid questions, but can you isolate which barrels are infected, and just use those for sour beers? Like, work with them, instead of against them?

[brewmaster 2011]

You say you do nothing to the inside of the barrel. To me, that is just inviting something to take over. If i plan on storing the barrels empty, I always burn a sulfer stick inside the barrel and bung it. if i plan on using the day they arrive I fil them with 180*f Water let them sit for 20 minutes minimal to steralize it.

[Terroir]

Dont stick anything burning in a fresh spirits barrel

[tsmack]

Thanks, all...

We have always avoided inside-barrel treatment to try to retain the highest level of flavor carry over in the quickest time (as I've found rinsing them brings down flavor contribution).

Everybody's ideas and insights are thoughtful and appreciated...it's just weird that we've been doing this for many years on a smaller scale and having no issues with things like grain dust from distilleries, not rinsing barrels, etc.

Anyway, we're moving to steaming the barrels and racking beer into the steamed barrels without dumping the sterile condensate if it's not too much...hoping we have no flavor loss (and maybe even a flavor increase by opening up the wood's pores?). I will post back in the coming weeks/months on this thread for how our rigorous new QC deems the outcome.

Thanks,

Taylor Smack
Blue Mountain Brewery
Blue Mountain Barrel House