Wednesday, April 11, 2007

The case of the unintended Brett cross-inoculation (aka Infection)

Well a few months back my buddy James and I brewed a Rye Mild. The brew went as planned, except for the fact that I forgot that I didn't have an open fermenter. No problem I said, we'll transfer my Mo' Betta Bretta clone out of its Better Carboy into some 4-liter jugs, sanitize the fermenter and put the rye in.

So we gave the Better Carboy a soak and scrub with hot water and OxiClean making sure that all the little bits of yeast gunk were gone. Then we gave it an extended soak, 30 minutes, in Iodophor. The beer fermented fine, and tasted as we expected for about a month in the bottles... then it happened.

About a week ago I cracked a bottle a got a slight Brett C fruitiness, must be a dirty glass or an off-palate, sadly a bottle the next day tasted the same and finally James confirmed my thoughts. Maybe it was the fermenter maybe it was some the the crevice or crook of some other piece of equipment harboring the invader, but it really doesn't matter now.

Here's the thing, the beer is now different, but still damn tasty. It's strange the beer doesn't seem to be building up much extra carbonation either. Only time will tell if this turn into a low-abv Flanders Bruin or a horrid gushing drain pourer.

As soon as I realized what had happened I gave every piece of brewing equipment I own (that ever touches beer post-boil) and gave it 6 hours in a heavy bleach solution followed by a full dry and then a soak in Iodophor.

Luckily either of the two beers I have done since then is showing signs of Brett activity, but they are both pretty young.

I guess this is a wake-up call to start taking sanitation and segregation more seriously, either that or stop brewing anything but wild beers...


brendan said...

Fully, I have done this now as well.

the brett is a serious ninja. I now have funky buckets and cornies. just seperate. I have clean and "nasty" hoses, and auto-siphons.

Also, it's kinda fun to have a regular pale ale develope some ORVAL leathery notes-- as in my case.


Anonymous said...

This is my concern as well. I am going to seperate bucket/hose/etc path for now. Should I be concerned about an airborne brett cross contamination?

The Mad Fermentationist (Mike) said...

It is still a very mild Brett note, and luckily we primed this one on the low side so I doubt that there will be much danger of explosive carbonation. I only have about 6 bottles left anyway, it was a low-abv beer so I’ve been going through it quickly. I think I’ll be moving to the separate equipment method as well, I had never had a problem before, but better safe than sorry.

I don’t think there is an airborne contamination issue, I know a local brewer who has two barrels filled with some delicious Brett beer that are right in the middle of his brewhouse.

Anonymous said...

Oh boy. Wasn't I just asking about this very thing? Hehe. I guess I will segregate.