Checking in on the recently filled lambic barrels

Last weekend I went up to check on the barrels from our brew day a couple months ago.  Given that this was the first time using a coolship, I was a little anxious to see how they were doing.

Taking a step back, I realize I haven't written anything about the brew day itself.  It was a full weekend and somehow everything went off without a hitch.  There is a great write up here summarizing the weekend better than I could.  The brewers at O'so have got the process down and are very efficient at doing what they do. Compared to previous years (which I have notes posted), there is very to add regarding the brewing.  Post-brew however, the wort went from the boil kettle to the coolship that had been temporarily installed outside under a large tent to rest overnight.

Coolship filling with lambic wort.  (photo credit)

From literature on the process, I was hoping the wort would be ~70°F the next morning.  We got in around 8:30 am and checked it with a digital thermometer which read 70°F exactly.  I was ecstatic to say the least. The inoculated wort was then pumped into a large tank to ensure everything was homogeneous, and then pumped into barrels.  Some of the barrels filled were straight from the winery and some of the barrels filled were previously emptied lambic barrels.  They were all thoroughly cleaned out with 200°F water prior to filling.

So, back to being up there and checking in on the barrels.  I was able to taste from barrels that had previously held our lambic, but the barrels that were our first use were tucked away such that we couldn't get to them without a forklift.  There was an event going on at the brewery, so I'll wait for another day to check in on those.  I am curious to see if there will be a distinction between the two sets of barrels.

I am a firm believer that, while a coolship imparts a new generation of microflora into the wort, much of the fermentation process is guided by the yeast/bacteria already in the barrel.  Cleaning the barrel, even at the high temperatures we do, will never sanitize the barrels completely and yeast/bacteria residing deeper in the wood will survive.  Through generations of culling barrels, a brewery is able to build a "house flavor".  You will find others who argue the relative impact of the coolship on the fermentation process is greater than that of the barrel.  Its an interesting argument if you really like nerding out about this stuff, and having these two sets of barrels is my way of testing things out.

It was interesting to taste the barrels that were accessible.  At this age there is little you can tell about how the beer will turn out, but I am able to see if its "on track".  First, I am making sure it did in fact ferment instead of spoil.  Given this was the first time spontaneously fermenting via coolship, that concern was lingering in the back of my mind.  But everything checked out.  It actually tasted almost exactly as the previous year's barrels did at this point.  It has a light tartness and an ever so slight brett character. The only difference I noticed from prior batches was there was a sweet lime flavor.  Is this an impact of local microflora?  In addition to these flavors, there is this phenolic flavor which we've noticed in previous batches as well. Its just an odd stage our lambic goes through. The reason I mention this is so home brewers who may be reading this know that these early off flavors are not a reason to dump your beer.  Honestly, there is no reason to even taste your lambic in the first 9 months.  I just do it for fun and because I can pull out of a sample port below the pellicle line.