Beer Style: Barrel Aged Mixed Culture Beer with Boysenberries
Final pH: 3.38
Final Gravity: 0.9° Plato
Packaged On: 30/04/2021
Our first brews to start our mixed culture program went into oak in late 2019. We waited patiently for the barrels to mature and show signs that this golden liquid was ready to enter its next phase of life. This day arrived 12 months later, as we selected some barrels that would work well with Boysenberries (supplied by our friends at The Berry Man)!
Barrels selected for this fruit blend were A21 (stone fruit aromatics, citric-like acidity), A23 (earthy, mustiness) and A32 (tobacco, leather, light lemon, barnyard/goat).
We sized our fruiting tanks to fit 400kg of fruit and three barrels of beer. This allows us to fruit the beer at a very high rate, then back blend with additional beer to achieve the fruit intensity we’re looking for.
Barrels selected for back blending were A24 (barnyard/goat, light oxidation) and A27 (light caramel, delicate barnyard aromatics), as well as our Petite Saison to balance acidity.
Detailed Tasting Notes:
Appearance: deep purple, fairy floss foam with lacing
Aroma: boysenberry cheesecake, lemon tart, honey, leather, tobacco, musty funk
Palate: berry parfait, lemon rind, firm acidity, subtle nuttiness
Mouthfeel: some tannic weight, creamy, perception of sweetness
The bottle conditioning process is essentially a secondary fermentation, and as such the beer will undergo similar changes common during the primary and barrel ageing processes. One of these is the formation of a pellicle, which is a reaction to oxygen by our mixed culture. We have observed this occur in nearly all of our primary fermentations and barrel ageing, but only in some of our finished bottled beer. The pellicle is an entirely natural part of the product, just like the sediment at the base of the bottle.
Deeds Mixed Culture Program Overview:
It’s nearly three years since we started brewing at our home in Glen Iris, and while we may have become best known for our IPAs, barrel ageing has always been part of our plans. Mixed culture fermentation, with or without fruit, is a love of ours and we’re excited to share these beers and expand this project. We’ve drawn inspiration from around the globe, from Lambic and Gueuze producers in and around Brussels, to more modern interpretations by American sour beer brewers.
The programme kicked off in the last quarter of 2019 when we welcomed our first delivery of wine barrels. We began by building up our mixed culture, preparing it to embark on the grand task that lay ahead. Ned had been brewing with this culture at home for a number of years preceding it’s new adventure at Deeds, and he was filled with a mix of excitement and trepidation to take it from 50 to 1500 litre batches!
Two base recipes were initially used to drive different fermentation profiles of our mixed culture. The first was designed to create similar characteristics to a traditional turbid mash used in Lambic brewing, utilising the same technique of boiling part of the mash, creating a dextrinous wort full of complex sugars for a long slow fermentation, as well as a hot sparge to layer some tannin into the beer. The second recipe also utilises a step mash, but is aimed at creating a highly fermentable wort, favouring a Saccharomyces yeast-driven fermentation, with less acidity in the final product.
The primary fermentation is conducted in an open top fermenter called “The Albatross”, which we converted from of an old, stainless steel grist case. From there, we transfer the beer into French oak for extended ageing. And then we wait.
We watch on as the barrels develop their individual characters, each slightly different from the next. When the beer is ready, we select them for either blending, or macerating on a fruit sympathetic to the character of the base beer. At this point, the production team sit down together for a final sensory session to select barrels and blend compositions for every beer.
In August 2020 new tanks arrived expanding our cellar for our first time. Along with three 100hL fermenters and two yeast propagation tanks came 6 stackable fruiting tanks for the mixed culture programme. These tanks are primarily used for fruiting mixed culture beer, but they also give us flexibility to run many projects simultaneously. Let’s just say these tanks came just in time.
Once the beer has finished ageing on fruit and/or the blending is complete, it is ready to be packaged. A small amount of sugar and fresh culture is added to allow for refermentation in the bottle. We use a 6 head gravity filler, allowing flexibility to fill a wide variety of bottle sizes, currently 375mL, 750mL, and even a few 1.5L Magnums! The bottles are then stored, allowing the beers to carbonate and settle. Scheduled sensory sessions allow the brewers to track the beer's progress and ultimately determine when they are ready to share. Finally they’re shipped to specialty bottle shops and bars across Australia for you to consume and enjoy!