Monday, January 23, 2012

Souring a Beer with Acid Malt - Ithaca Brute Style

It is hard not to get embedded in a rut when you really get into brewing sour beers. The investments of time and effort are so big that it discourages major risk taking (just take a look at all of the lambic brewers who essentially brew only one beer!). While I'm confident enough to adjust the grain bill, or add interesting new ingredients, my basic method hasn't changed much since I stared to be happy with the results a few years ago. As I hinted at in my Great Souring Experiment post, I’d like to try mimicking the methods that several respected craft breweries are using. I doubt all of these batches will be as good as my default, but maybe I will find a way to make sour beers that is faster, more reliable, or produces a unique flavor.

The Brett will look more interesting eventually.My first attempt at a new method was to use the one that head brewer Jeff O'Neil developed while at Ithaca Beer Company to produce the pale sour Brute. He has since moved on to Peekskill Brewing, which sounds like it will allow more freedom for him to experiment. The basic idea of the method is to use a significant proportion of acid malt in the mash, a hot saccharification rest, and a clean primary fermentation with only Brett pitched into secondary. The combination of mashing at both a low pH and high temperature creates a largely unfermentable (to brewer's yeast) wort. Brute starts with a hot primary fermentation with their house English ale yeast and then crash cools when it reaches about 50% apparent attenuation. Oak spirals and Brett Drie are then added and allowed to age for close to a year.

I started the mash for my inspired by batch at 159 F and allowed it to convert before adding the acid malt. Ithaca does not wait to add the acid malt, but I was a bit worried about getting really terrible starch to sugar conversion. I initially added 1.5 lbs of the tangy sourdough-flavored acid malt from Weyermann. When this didn’t result in a pH as low as I expected I added another 1.5 lbs. Now at 20% acid malt, the mash made it down to a pH of 4.5. As pH is a logarithmic scale, the final pH of Brute ~3.7 would require more than six times as much acid to reach. On their website Weyermann suggests 8% acid malt to sour a quick Berliner weisse, but I don't see how this would work when 20% in this beer gave no noticeable acidity.

I'm interested to see how far the Brett will be able to lower the pH on its own, it is also possible that Brute had other microbes, which had not been pitched, at work in the dedicated tank. Jeff has also said that he felt that seasonal temperature swings were a big part of what made Brute work, so I'll be letting this batch sit outside of my temperature controlled basement "fermentation" room next summer... maybe.

I failed to take many pictures during the brew day, but the American University journalism project were around throughout the day snapping photos of ever step of the process.

Acid Malt Soured Saison

Recipe Specifics
Batch Size (Gal): 5.50
Total Grain (Lbs): 15.00
Anticipated OG: 1.069
Anticipated SRM: 4.1
Anticipated IBU: 10.1
Brewhouse Efficiency: 67 %
Wort Boil Time: 90 Minutes

66.7% - 10.00 lbs. German Pilsener
20.0% - 3.00 lbs. Weyermann Sauer(acid) Malt
13.3% - 2.00 lbs. Wheat Malt

0.50 oz. Hallertauer Tradition (Pellet, 6.00% AA) @ 60 min.

WYeast 3726 Farmhouse Ale

Water Profile
Profile: Washington DC

Mash Schedule
Sacch Rest 45 min @ 159 F
Acid Malt Sacch 30 min @ 159 F

Brewed 12/04/11 with my neighbor Josh and the American University journalism crew

Mashed 45 minutes before adding the 1.5 lbs of Weyermann acid malt, waited 15 minutes, and pH was still at 5.5, added 1.5 lbs more which took it down to 4.5. Not quite as sour as I wanted, but it should be interesting.

Double batch sparge. Ended up with a bit more gravity than I wanted. Pitched yeast cake from one carboy of the first refill of the apple brandy solera. Shook to aerate.

Fermentation was going strong after 12 hours at 64 ambient. After 24 hours total I added 1 gallon of distilled water to lower the gravity.

After 48 hours placed it in a pot on the radiator to get it up to ~82 F.

12/10/11 Racked to secondary, down to 1.015. Not much acidity, I may have to pitch more microbes that I was intending.

1/13/12 Added ECY Brett Blend #1 via dregs from my Brett'd Rye Saison.

10/29/12 Bottled 2.25 gallons with 2.5 oz of table sugar. Finished at 1.007 (8.2% ABV), lower FG than Brute. Racked the rest onto ~4 lbs of frozen/thawed white nectarines.

1/24/13 Bottled the 2.5 gallons on fruit with 2 1/8 oz of table sugar. Great fresh nectarine aromatics.

6/10/13 Tasting notes for both the plain and nectarine versions. Very pleased with both, solid acidity, appealing flavors, very drinkable despite the strength.


brewcrew76 said...

Tried a similar experiment based on the Ithaca Brute recipe Jeff gave out on the Brewing Network. Here is the recipe Jeff gave:

Mash at 162
White Wheat
Red Wheat
12 % Flaked Corn
13% Acid Malt
Ferment 3 days with ale yeast, then transfer and add Brett

My recipe (brewed 5/24) started at 1.060 and only got down to 1.042 after 4 days. Stayed at 1.042 for 2 more days so I transferred and pitched Wyeast Brett Lambicus. Never tested PH and not sure why ferment stalled at 1.042. Notes when transferred - blend of fairly sour and sweet at same time with a grainy tartness.

Was down to a steady 1.010 in October (6 months later) so I bottled a 12 pack and added Door County tart cherries to the remainder (still in carboy). I am happy with the bottles and think they matured quicker than other Brett beers I have done. Haven't taken notes yet on the bottles but can update when I do.

Adam said...

You have to remember that additional pH lowering will likely occur during the fermentation. I've never really tested pH of unfermented wort in comparison to fermented wort in a clean beer but there is a drop in pH. I'll have to check that this next batch.

Seanywonton said...

Looks like we are almost on the exact same time frame with very similar beers!

My 13% sour malt got me nowhere near sour enough, and I added a 24 hour sour mash which got it really sour, but I didn't have a pH meter to get a number.

I pitched Brett B and Brett L into my amber farmhouse base a couple weeks ago, and it's starting to crunch the gravity down. I'm aiming to give this no more than 6-8 weeks on the brett, but I'll go longer if it needs it.

Next up is a berlinner weisse with a full sour mash, then bottle off a bit after a clean primary ferment. Then split the batch and add the Brett B/Brett L blend to 1 carboy, and only Brett B to the other.

I'm going to be back out east in March or April. Moving back to Ohio. Maybe a swap and tasting is in order!

Anonymous said...

You kept the IBUs fairly low. Knowing that the sour malt didn't do as much souring as you anticipated, do you think this beer could handle a bit more bittering?

The Mad Fermentationist (Mike) said...

That is the sort of ultra-low attenuation I was worried about, glad to hear the Brett ended up chewing through it. Glad it turned out well.

Certainly the pH will drop, I'm just suspect that it will drop enough to make it a truly sour beer. The way pH works it is much more acid to drop from 4.0 to 3.7 than it is to drop from 4.3 to 4.0 for example.

It’ll be interesting to read your notes on how well yours turns out. I’m tempted to just dump in a bunch of microbes, but probably better to just see how it works with Brett only. Where are you moving to in Ohio, Audrey is from outside Dayton and we should be driving through sometime during the summer.

It is hard to judge, if it doesn’t drop much below pH 4.0 it could certainly take 25-35 IBUs, but much lower and it could take more. I’m already about the same gravity that Brute finishes at, so it is hard for me to know how this beer will end up.

Seanywonton said...

I'll be moving to Athens Ohio and working at Jackie O's as the pub brewer. Brad Clark, the Jackie O's brewmaster, is going to take on the new production facility. We'll be sending out an "official announcement" soon. You guys will have to swing by! If you come up 33 to 70, it would be right on the way.

The Mad Fermentationist (Mike) said...

Excellent, easy stop for me on the way to Dayton. Congrats! Only had a couple beers from Jackie O's, but they have all been good.

Jim Lemire said...

Just listened to the recent BN podcast with Jeff O'Neill - it sounds like Peekskill is going to be one amazing place. Just the brewery/pub set up sounds incredible.

Also, I drank one of my acid-malt sours last night (13% of the grist) and, while I think it is a good beer, I found it lacks complexity. It was pretty sour, but I don't know how much was the acid malt and how much was the cranberries, but I couldn't help thinking that it needed a little citrus flavor to 'brighten it up'. Curious to see how yours turns out.

Dank brewer said...

what is the final gravity of Brut?

I just picked up ingredients to try something very similar to a Brut clone although the aged hops I could get were Vanguard and Palisade. Planning on fermenting it with ECY03 Farmhouse Brett since I have a nice yeast cake of that ready to be used. Recipe seems similar to Brewcrew76's but with 19% acid malt.

The Mad Fermentationist (Mike) said...

Shockingly 1.016ish. Good luck!

dank brewer said...

So if I wanted to replicate Ithaca brute's style for fermentation I'd pitch some English yeast in primary and secondary with Brett C and oak chips?

The Mad Fermentationist (Mike) said...

Yep, pitch English yeast (preferably Whitbread), let it ramp up into the 80s, and then crash chill when it gets close to 1.030. Then rack and pitch a big starter of Brett Drie (White Labs will be releasing it as Brett Brux Trois this summer). Ithaca uses light toast French oak spirals, but cubes would work fine as well.

Peter said...

I followed Weyerman's advice on 8% acid malt to make a Berliner weiss. I was skeptical, but I was really shooting for something like Bell's Oarsman, which is more subtly acidic than a BW. I used 9.5% acid malt. I did not find the approach sufficient even for the subtle acidity I was going for. I would not have commented on any sourness in a blind tasting.

TGTfan said...

Made a blackberry wheat with about 25% acid malt (capped a mash of 7# wheat, 5# vienna with 1# wheat, 1# vienna, 2# acidulated malt - ended up with about 50% of the total sugars so figure about 25% should be from the acid malt). The resultant beer was a great summer drink - very crisp and a lighter mouthfeel than the non-soured batch due to the lower pH (both had a low FG - 1.007), sour but not bracingly so. 4.7 abv, 14 IBUs.

Quite pleased. Will likely brew it again this summer.

TGTfan said...

I imagine the results for a given percentage of acid malt are going to very based on the buffering capacity of your brewing water though, yeah?

The Mad Fermentationist (Mike) said...

The buffering capability of your water and malt will certainly play a role in how sour a lightly acidified beer becomes. However, the amount of acid required to make a really SOUR beer is so great that I don't think these things would have a large impact on the final pH.
Sounds like a tasty beer, glad it turned out well!

Dank brewer said...

Took a ph reading of my Ithaca Brute clone (23% acid malt) and it's sitting right around 3.9/4.0 and it's tasting nice and tart, but not bite like I typically enjoy.

Adam said...

I'd like to add that I've recently done a quick sour saison in this fashion. Before fermentation the pH was around 4.0. Now that fermentation is over it's at about 3.5. I split the batch between ECY03 and a grown up Dupont culture from a bottle. The ECY03 cruised through the wort in record time for me. The dupont half is still going. I may add some 3711 to the fermentor to hopefully get it to finish up. I would like to bottle the two blended after bottling about a 12 pack of each separate.

The best way I can describe the sourness is yoghurt like acidity. It is nothing like the ECY20 soured saison I did with an almost identical recipe (spelt with ECY20 instead of flaked wheat). This might make a refreshing brew with a slight tartness but it's not a truly sour beer that triggers the parotid salivary gland.

Mattea said...

This is an old thread but i brewed 2 beers with 20% and 40% acid malt, so I still like to post/ask something. the fermentation is with only brett drie. problem is that 10 days into the fermentation the yeaast stalled at 1.030. the beer doesn't taste sweet at all. I added the acid malt at the beginning of the mash so i'm thinking the conversion didn't go so well. I mashed quite low though. 66 C for well over an hour.

about the taste: acidity is there, but covered up by the full body of the beer. i'm probably pitching brett b from wyeast to try to get more larger sugars to be eaten by the competing bretts. hope it wil work out fine.

am i missing something else maybe?

The Mad Fermentationist (Mike) said...

Yep, most likely conversion issues. A variety of Bretts isn't a bad idea, but you may have to resort to Beano or enzymes if the bugs don't get the job done.

Unknown said...

i have 200 ppm of bicarbonate in my water, it's quite hard. Don't know exactly about Washington DC water but if i'm correct somewhere i've read that you have about 100ppm of bicarbonate in your tap water. Is it correct?

I fear that there's too much buffering capacity in my tap water for this tecnique and i'm willing to use another water for this beer.

The Mad Fermentationist (Mike) said...

You could certainly dilute with RO/distilled water by 50% to get closer to DC water, but a pH meter and extra acidualted malt as needed would be a better option.

Unknown said...

i've done a saison in this fashion. It's in the primary from one week. Mashed at 71°c (20 minutes and then added the sauermalz for additional 30 minutes) good efficiency (about 70%) but i don't have made the test for starch conversion. The final ph and the mash-out was 4.5, i tought it was a good place to start. Yeast was m27 (belgian ale from mangrove's yeast that seems to perform really like french saison plus slurry from my previous saison with dupont strain and a variety of bugs in there).

Now i regret that i didn't made iodine test because in 6 days gravity is dropped to 1003 from 1046. So i must suspect that conversion was completely done in the mash despite of the high amount of sauermalz or maybe the m27 (pretty much like belle saison) it's capable of eating dextrine and maybe even....starches???

The Mad Fermentationist (Mike) said...

Wow, especially given the hot mash I wouldn't have predicted that. Next time you could try starting with the acid malt in there, not giving time at the proper pH for the whole mash to convert.

Starch fermentation would be unlikely, given that not even Brett is capable of that. Don't know anything about M27, but certainly sounds like Belle in terms of high attenuation.

The only other suggestion I have is to calibrate your thermometer, make sure it reads 100C in boiling water.

Unknown said...

yes, i'm suspecting some thermometer issue too, i'll do the check. One thing to clarify: you say that not even brett is capable of starch fermentation. But brett eats starches in the end, you mean it first break them and then ferments the simple derived in a much more longer time?

The Mad Fermentationist (Mike) said...

To ferment dextrins Brett produces alpha-glucosidase. It has limited activity up to 9-glucose molecule dextrins. Some Pediococcus isolates ARE capable of starch breakdown, which may make the component sugars accessible to Brett.

Unknown said...

I think i must re-read your book once again.. :) i had some confusion about brett and starches. So the huge amount of starches that comes out from a turbid mash needs a heavy and healthy culture of pedio to generate a the finale dryness of a lambic while, for example, a turbid mash followed by inoculation of sacc + Brett but without bactieria would end in a low-attenuated beer.

I've checked the thermometer and it's ok, for the future i'll follow your suggestion to insert sauermalz from the beginning of the mash and, second, i'll exclude m27 that, as well as belle, it's devastating and leaves the desert behind him. I've read somewhere that belle (and i suspect m27 too) it's a sacc cerivisiae ssp. diasticus cabable of dextrine breakdown...

The Mad Fermentationist (Mike) said...

Correct. Wild Brews suggests the same thing on page 144, "The lactic acid producing bacteria require the starch, present in the adjunct grains, to produce their requisite byproducts...Any beer that requires lactic acid development can benefit from some starch."

Not sure how "huge" the amount of starch that is extracted by a turbid mash actually is. I haven't seen a carbohydrate profile for a traditional lambic wort.

Unknown said...

thank you mike, you're very kind and i disturb you one last time: could be a valid remedy/improvement for the beer i've made to add now some starches in the secondary..i could add some maize starch in solution. Well, hoping that the pedio i should have in the bugs added via bottle dregs will be there, and healthy enough, to work on that starches.

The Mad Fermentationist (Mike) said...

I'd go ~.5 lbs maltodextrin, less risky, easier to deal with.

Unknown said...

ok. Thank you!