Brewing a 100% Brett IPA (with Galaxy and Southern Cross)

In late July, I posted about my first 100%-Brett IPA, a light-coloured beer with plenty of late-hopping: all Amarillo after knockout, and a big dry-hop of Hallertau Blanc. Fermented with The Yeast Bay's Amalgamation, a "Brett Super Blend" featuring six different Brettanomyces strains, the beer came out really tasty. It had just what I was looking for in a Brett IPA, with lots of tropical, fruity hop aroma and flavour, with just the right balance of Brett funk. Mouthfeel was creamy and very smooth, with - for me - the perfect amount of bitterness (let's say medium-low).

In that post, I threatened to brew the same recipe again and change the hop varieties, and that's exactly what I did in late September. I felt absolutely no need to change the grist for this beer; as mentioned above, the body was perfect. Despite my initial worries that the Brett strains would not produce the glycerol needed to boost mouthfeel, the combination of a good proportion of wheat malt (21%) and higher mash temp (153 F) seemed to do the job nicely. When I initially made the starter for the Amalgamation blend, I built it up enough to have twice as many cells as I needed. Yes, it had been three months since then, and I needed to make another starter, but the slurry looked and smelled healthy enough to me. So, I got the Brett into some more wort and onto my stir plate, aiming for ~300 billion cells (200 for this batch, and another 100 to have on hand for another time). The starter seemed quite active; there was a large krausen that actually overflowed from the flask a little, before settling down as activity slowed.

For this batch, I wanted to stick to two hop varieties again. While I had considered doing a single-hop brew, I had so many I wanted to experiment with Brett that I knew I'd have to pick at least two. Like last time, I was mostly looking at hops that would offer a lot of tropical fruit and/or citrus character, to complement the fruity/pineapple aspects that you often see in 100% Brett IPAs. I finally settled on two Southern Hemisphere varieties: Galaxy and Southern Cross. I've brewed with both before, but never together. Australia's Galaxy is found in plenty of commercial beers, and is well-known for adding plenty of tropical fruit. I had used Southern Cross (New Zealand) in my Alpine Nelson clone, and really liked how it worked with Nelson Sauvin: it's citrusy characteristics paired perfectly with the gooseberry of the Nelson.

Otherwise, I kept everything about this beer exactly the same - grist, mash temps, Gypsum and calcium chloride additions, etc. This time around, my mash efficiency was a little low (compared to a little high the first time), which I can't really explain. Aside from that, the brew day went smoothly. I had cold-crashed the Brett starter several days prior, decanted the large amount of beer off, and then "woke up" the yeast with another 500 mL of wort on the stir plate for a couple of days, before pitching the starter at 66 F into the chilled wort. I then aerated with pure O2 for 75 seconds. This is exactly the same procedure I followed for my first Brett IPA; by the next morning for that beer, fermentation was coming along nicely.

Not this time. When I checked on the carboy the first morning after brew day, there was zero visible activity. The airlock wasn't bubbling, there was no krausen; you could see the trub/yeast cake sitting on the bottom of the Better Bottle. I was confused. The temperature was still 66 F, and there wouldn't have been any drops in temp overnight. When I checked on it again that evening after work, there was no change. By the next morning, I was starting to panic when there was STILL no activity. I knew I had pitched enough yeast and aerated well, but I pitched a little more slurry (approx 40 billion cells) just in case, as a last-ditch effort. My plan was if it wasn't doing anything by that evening (which would be a little over 48 hours since the original pitch), I'd have to add some US-05 and see what happened.

Luckily, when I got home from work, there was finally bubbling in the airlock. Fermentation grew strong and continued nicely, bringing the beer to a final gravity of 1.008 (quite a bit lower than I had achieved with the first Brett IPA). But why did it take 48 hours to get going? Yes, the slurry I had saved from the original starter was about 3 months old, but I took that into consideration when calculating the booster starter size, and should have had plenty of cells pitched into the wort. Not to mention the fact that the starter was extremely active, as noted. Whatever the reason, I was slightly nervous as to how the end result was going to taste.

After about 2 weeks, I dry-hopped the beer in primary for 5 days, and then kegged it. The first time around, I had bottled the beer so I could get a good idea of how it developed over time with the Brett. It still tasted great after four months (when I consumed the last bottle that I had saved), but the hop character, as expected, had faded considerably. And it was when the beer was really hoppy that I enjoyed it the most, so I was looking to keg it for this batch, to keep the hoppy goodness around as long as possible.

This turned out to be a very interesting beer. Despite the fact that the only real change to the recipe was the hops used, it tastes a lot different than the first batch, to me. The first time I poured a sample, before carbonation was really where I wanted it to be, I got a huge blast of pineapple and tropical fruit... and I mean HUGE! I immediately loved it. But since then, I haven't been as crazy about it. Not to say I don't like it, but for the next several pours, I wasn't sure where this beer was headed. I hate to say it, but I swear with the second or third pour I was tasting and smelling... urinal. I wasn't sure if it was how these particular hops were working with the Brett strains, or if it was that the Brett had really taken a turn for the worse somewhere down the line, but I was starting to get worried again.

However, now the beer is tasting fine. I must say I prefer the Amarillo/Hallertau Blanc beer, but the Galaxy/Southern Cross combo really settled into its own after a little time. That pineapple and tropical fruit presence is still there in spades, but the funk backs it up quite well. I find the "funk" different than in the first beer, and I wish I could explain exactly how... but I can't. It's just different. Not unpleasant, but not the same.

I really need more people to try this beer, but only a few others have as of right now. Those that HAVE tried it seem to really enjoy it, but I'd like some more input. I've been drinking it for about a month and haven't noticed it changing too much, yet; the kegging has definitely helped in that regard. My real concern now is, is the small amount of yeast slurry I've saved for the next batch trustworthy? I'm planning on brewing another 100% Brett beer soon, so I guess it won't be long before I find out...

Recipe Targets: (5.5 gallons, 75% efficiency) OG 1.057, FG ~1.010, IBU ~52, SRM 4.1, ABV ~6.5%

Grains:
3.7 kg (71.2%) Canadian 2-row
1.1 kg (21.2%) Wheat malt
200 g (3.8%) Cara-Pils
200 g (3.8%) Acid malt

Hops:
Hop extract - 5 mL @ 60 min (or 28 g of a 10% AA hop variety)

Galaxy - 35 g (12% AA) @ 0 min (with a 20 min hop steep)
Southern Cross - 35 g (13.5% AA) @ 0 min (with a 20 min hop steep)

Galaxy - 35 g @ 0 min (when start chilling)
Southern Cross - 35 g @ 0 min (when start chilling)

Galaxy - 63 g dry-hop for 5-7 days (in primary)
Southern Cross - 63 g dry-hop for 5-7 days (in primary)

Misc: 1/2 tab Irish Moss at 5 min

Yeast: Yeast Bay Brett Amalgamation (slurry, ~200 billion cells)

Water: Fredericton city water, carbon-filtered; 3 g Gypsum and 3 g calcium chloride added to mash

- Brewed on Sept 22nd, 2015, by myself. 50-minute mash with 15 L of strike water, mashed in at 153 F. Mashed-out for 10 minutes with 6.75 L of boiling water. Sparged with ~3.5 gallons of 168 F water for final volume of ~6.75 gallons.

- SG 1.045 (low, target 1.047). 60-minute boil. Final volume a bit high at 5.75 gallons; OG 1.055. Chilled to low-60s F, then poured into Better Bottle. Aerated with 75 seconds of pure O2, pitched yeast slurry at 66 F.

- After about 48 hours, activity finally became apparent - bubbling in airlock, krausen forming. Continued quite vigorously for 2 days, then began to slow down. Temp got up to 72 F.

- 7/10/15 - FG 1.008. Dry-hopped in primary. Kegged 5 days later and set in keezer to bring temp down before starting to carb the next day.

Appearance: Pours with a small-moderate sized white head, which fades fairly quickly to a thin film on the beer. Body is a light-golden color (that picture isn't the best representation), and very hazy, almost cloudy, even after a month or so of being kegged.

Aroma: Definitely an interesting aroma - while it's quite obvious this is a hoppy beer, with it's strong pineapple, citrusy smell, there's a very strong funkiness that comes through easily as well as the hops. It's not really barnyard; I can't quite put my finger on it.

Taste: A little more well-rounded than the aroma, I'd say the hops win - slightly - here. Lots of powerful fruit flavours coming through, but yes, still a good amount of funk. Medium to medium-low bitterness in the finish, quite dry and a bit tart. More white-wine like than the last Brett IPA.

Mouthfeel: Medium-light bodied, moderate carbonation. Quite smooth and creamy.

Overall: Very tasty. I'm happy with the mouthfeel and finish of the beer; definitely a bit drier than the last one. I don't think the differences in this beer are completely due to the different hops used, but either way Galaxy and Southern Cross are working really well together, here. Let the experimenting continue!