At the event, we livestreamed the conversation and posted the video, which you can watch above or directly on YouTube.

Highlights

Here are some of the details about Brut IPA and it’s origins from the video.

Origins

Sturdavant learned about the enzyme (amyloglucosidase) from Tim at Cellarmaker and started using it 2 years ago in a Triple IPA to reduce the sweetness of the beer and make it “more approachable and pleasant to drink.” Since first using it, he had been interested in using it in an standard IPA, to “make an extremely dry and champagne-like IPA … super pale in color … so it looks like one thing and tastes like another.” The first batch Sturdavant made was in November 2017, which he called “Hop Champagne.” After speaking with a friend from the wine world, the term Brut seemed to make sense to describe something very dry and easy enough to convey to the consumer what it is.

Rules of the Style

“As pale as possible in color”

“It needs to be very dry … knock it below 1˚ Plato” and get it as close to zero as possible

“It needs to be in balance and very good and tastes really good … a very hop forward IPA.”

More Details about the Style

Use of adjuncts is personal preference of the brewer. However, Sturdavant like to use adjuncts to get the color as light as possible and rice and corn help to achieve that goal. He also feels that it some complexity to the grain profile so that it’s “not just one dimensional.”

Sturdavant does not use a champagne or wine yeast. He feels that these yeast strains do not add anything to the beer because they too neutral, which makes sense for wine to allow the grapes express themselves. Instead he like to use his house yeast for his Brut IPAs.

For this style he prefers hops that are “high in oil, resinous, tropical” basically hops with a sweet profile. He feels that hops with grassy aromas might make it seem gritty and hops with earthy aromas might make it seem fuller than it is.

Sturdavant is not concerned with the clarity of a Brut IPA. It can be hazy or crystal clear. He likes to be able to see his fingers through the class and prefers not to have a bunch of yeast and protein in suspension.

Bitterness, “needs to be super in-check” according to Sturdavant. The Puttin On the Spritz Brut IPA is 22 IBU as compared to a standard IPA being 55 IBU or more.

In terms of carbonation levels, Sturdavant serves Brut IPA the same as the rest of the beers on their draft system, which is 2.5 volumes of CO₂. If he could take it to 2.8 he would but their draft system just isn’t set up for that.

Software for self-distribution and coming soon Beer Production.

At what point do you add the enzyme?

This is something that Sturdavant is still playing around with. In his latest batch, which was served at the brewery during the event, he used it in the mash but was only able to get it down to 0.8˚ Plato. In the next batch he plans to use a little more to get it closer to zero Plato.

In all previous batches, he was adding during fermentation. However, he has a hypothesis that the enzyme might be affecting the hop profile during fermentation. He has found that despite the amount of hops being added they were not as aromatic as he expected. Especially compared to the recent batch, Puttin On the Sprit, zwhich was more aromatic.

Adding the enzyme during the mash also has the benefit of stopping the enzymatic reaction so that you don’t have a “never-ending reaction” in your fermentation.

Sturdavant admits that fermentation still might be the best route but he’s exploring the other options now to discover which technique is truly the best.

Dave’s note: I can attest that Puttin On the Spritz (the “recent” batch mentioned above) had more fruit and “juicy” characteristics than other Brut IPAs that I’ve sampled. Champagne Hopi by Alvarado Street Brewing is another beer that was a little more fruit forward than others but Sturdavant has informed me that Alvarado St. uses the enzyme in the fermenter.

About the Enzyme

The enzyme is an amalyse called amyloglucosidase, which is derived from black mold.

If you ferment a batch with the enzyme and harvest the yeast, it will still be in the yeast and even a small amount will continue to react. If you re-pitch the yeast for another Brut IPA batch, Sturdavant recommends adding a little more enzyme. What’s leftover in the yeast isn’t quite enough but you don’t want to re-use that yeast for any other style.

The enzyme works at fermentation temperatures but at warmer temperatures, the quicker it works. In the mash at 150˚ F it works much quicker than at 68˚F.

The enzyme is liquid in form and you only use 4 ml per barrel (31 gallons). Homebrewers will have to dilute it down a bunch if they want to use it to make a Brut IPA.

Enzymes like this one are used to make low carb beers effectively making a Brut IPA a low-carb beer.

Other Breweries and Brut IPA

There are breweries in on the East Coast US, England, Brazil, New Zealand, Australia, France, and Russia that have reached out because they are interested in this style. Not only that, some breweries are starting to experiment by using wine grapes and Sturdavant thinks that’s a great idea when it accentuates what’s already happening with the beer.

Update, July 11, 2018: Corrected that amyloglucosidase is made from black mold not malt. Included the detail that Alvarado Street uses the enzyme in the fermenter.