Attenuation!

J A

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Ya gotta love it when a plan comes together!
Attenuation has been a little elusive for me on a lot of brews. Getting that last few percentage points is hard. When beers are 1.011 instead of 1.009 it doesn't hurt much but it would be nice if they get there. It seems like I don't end up breaking 80% attenuation very often. That's acceptable and expected with British yeasts but I'd like to be seeing better with Chico and lager yeasts.
I had occasion to do a batch where highest alcohol production was the most important factor - body and flavor not so much. The most alcohol-tolerant yeast I had on hand for it was Nottingham so I decided to give it a go. I did a basic grist of good 2-row plus 10% Vienna and some Acidulated malt. The most important piece of the puzzle was mash temp and duration. My typical routine is to start with a dough-in/protein rest and add liquor and raise temp to 148 and hold for about an hour and then add and raise to 158 and hold for a bit before raising to mash-out temp. This time I intentionally started my Beta Amylase rest at a lower temp - less than145 - and eased it up to 148 over the course of a couple of hours. Then I pushed a little higher but only to 150 or so over another hour. I did a combination of simple infusion (still) rest and RIMS lautering to keep the temp steady.
The OG I wanted maxed out my tun and I had to do without a sparge. That always hurts efficiency but I still approached 80% efficiency out of the mash. I used the opportunity to split/gyle some wort for a 1.044 lager wort as well so overall efficiency was helped.
The wort I got for the "high-gravity" batch was 1.072 and I pitched the Notty at 78 degrees right off the chiller. I used 3 packets of yeast pitched dry onto the wort and since I had splashed a huge head of foam going into the fermenter, I didn't bother with O2. I turned the temp controller down to 65 so it wouldn't go crazy with a monster krausen overnight and reset to 68 next day.
I checked the gravity on the morning of Day 3, less than 60 hours in, and the gravity was 1.008!! I reset the temp to 76 to wring out any little bit of extra activity but even if it doesn't go further that's pushing 90% attenuation!! Distillers' yeast will take things further but for a beer yeast (British stain, no less) that's pretty impressive!
It'll be interesting to see how the lager split finishes out. Same mash temp, etc, with big pitch of Apex Berlin yeast and fermented at 52 degrees - this morning (day 4) it was at about 1.020 and I raised temp for D-rest. It'll be pretty awesome if that one goes to 1.007 or so.
 
Notty does go insane. It has some weird off flavors i don't like, but it can chug through wort.

IN general i don't like exceeding attenuation very much. Means it went too fast or something else helped. ;)
 
Notty does go insane. It has some weird off flavors i don't like, but it can chug through wort.

IN general i don't like exceeding attenuation very much. Means it went too fast or something else helped. ;)
I use Notty (and will be using Apex Sherwood) quite a bit. I keep the temps around 64 degrees for fermentation and find it to be more "clean" with less fruity-ester-y flavor than S-04. I definitely like it for my Guinness-style stout and Irish Red where I want to push it towards a dry finish. Most of the time I get around 78% with Notty as opposed to 76% with S-04.
With beer we're used to mashing for dextrins which will remain unfermented and add body and flavor but if we're pushing for maximum maltose and minimizing un-fermentable sugars, there's no reason to expect attenuation to not be in the higher ranges.
 
Haven't used s04 much either. 1098 is my go-to English
 
at 1.072, you're right at the edge of tolerance for a lot of yeasts, but 2 packages was probably enough or a single pack with a starter, typically what I do, because I horde yeast and it's not always new. Getting that without a sparge... #Respect. I've done 1.070 on my Anvil 10.5 before, but it was a bunch of work.
 
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at 1.072, you're right at the edge of tolerance for a lot of yeasts, but 2 packages was probably enough or a single pack with a starter, typically what I do, because I horde yeast and it's not always new. Getting that without a sparge... #Respect. I've done 1.070 on my Anvil 10.5 before, but it was a bunch of work.
And that's with a 10-plus gallon split batch (2 different OGs). If I'm shooting for a straight 8 gallons out of the fermenter and maxing that tun with no-sparge, I could hit 1.080 plus at 70% efficiency.
Even with my 5-gallon small batch set up, the tun is big enough to get me almost 1.080 with over 6 gallons going into the fermenter. I'll play around with some higher gravities at some point but it'll take either big Belgian ale yeasts or distillers yeast to work those worts. :)
 
I did a 1.200 in my 7 gallon kettle. Got 4.5 gallons out of it. 18lbs of grain, lol
 
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personally I think the grain brand is crucial, I've had some Munich "not sure what brand" that didn't produce and at least 1 point off from normal so it does make a difference
 
I also have a good history of low to high mash temps that worked the best meaning 140 to 155 slowly
 
personally I think the grain brand is crucial, I've had some Munich "not sure what brand" that didn't produce and at least 1 point off from normal so it does make a difference
Agreed. For a while one of the brewers around here was importing Sekado and we could get it at great prices. That stuff was magic. The floor malted Pilsner was super rich and converted very well and the Pale Ale was fantastic. I ran everything with that malt for a year or more and always got thru-the-roof efficiency with it. :)
I also have a good history of low to high mash temps that worked the best meaning 140 to 155 slowly
I've been bumping to 148 relatively quickly and easing up fairly slowly on my way to 158. Next time I do a lager or similar, I'll start in that 136-140 range and ease up to 152 or so. Maybe raise it up to 158 for a few minutes just to see what the malt has left.
 
It looks like my lager is going to go hard...it was at 1.006 this morning which is pretty good. I just checked it and it seems to be about 1.003. It may be a Brut lager before it's all said and done. :D :D
 
I hope it stops before it goes into negative numbers…
 
It looks like my lager is going to go hard...it was at 1.006 this morning which is pretty good. I just checked it and it seems to be about 1.003. It may be a Brut lager before it's all said and done. :D :D
let's hope it's not ending up a Brett lager :eek:
 
let's hope it's not ending up a Brett lager :eek:
Nope...clean as a whistle. Just a super fermentable mash and a massive pitch. I trust my fermenter and overall Only fault I can find with it at this point is that the hops are not coming through much at all. When I did the split and sparged/diluted to get what I need for the lager wort, I threw some extra gypsum in but the water profile for the main mash was for malty, not hoppy. I only used Saaz and it's only 20 IBUs so I don't expect any real bitterness but I'm hoping that when the yeast starts to clear, the hops will show up a little better. :)
 
Okay, then...
This lager has been in the keg for 8 days after being crashed in the Uni for about a week. It didn't drop as much yeast slurry as I expected, but then, there was pretty heavy load still in suspension at kegging. I used a pretty good dose of Bio Fine and let it sit for about 4 days before even starting to try to clear it. I didn't pull a lot at any given point but the first pint, of course was thick yeast. Samples over the last few days have been still pretty cloudy and not particularly great. I attributed that to the remaining yeast load (it's a lager, after all...it needs some time to clear)

So this evening I pulled a sample that was substantially clear and clean enough to be able to taste the beer rather than the yeast. I have to say that it's an interesting outcome...different from other lagers I've done but I think it'll be quite a good beer when it lagers out completely. I thought that with the attenuation, it would be dry or thin but it's neither. It's really quite rich and the malt flavor is pretty dense, as if it was a decoction. I think that's attributable to the very long, low mash extracting a lot of good stuff from the grain.

Even though the OG was low 50s, it's a solid 6.5% beer and the alcohol seems fairly noticeable, both in flavor and effect. :) The ABV pushes it into Helles Bock/ Maibock territory and the richness of the malt supports it pretty well. I was initially concerned about hop balance but aside from balanced toward maltiness, the hops are doing fair dinkum in the scheme of things.

Not ready to fully claim a win but way more optimistic than I was with the last couple of samples. PS...sampling this evening consisted of hitting the keg 2 additional times to top up...a good indicator, I suppose. ;) I might even grab just one more small sip before it's all said and done. :)
 
Not ready to fully claim a win but way more optimistic than I was with the last couple of samples. PS...sampling this evening consisted of hitting the keg 2 additional times to top up...a good indicator, I suppose. ;) I might even grab just one more small sip before it's all said and done. :)
I think 3 samples in one night put it in the Win column! ;)
 
I think 3 samples in one night put it in the Win column! ;)
I have continued to monitor the situation and can confirm that it seems to be quite acceptable, indeed. :)
It's clearing very nicely and the malt is strong and clean, I think there are lingering notes of yeasty flavor from the massive pitch but nothing that's particularly off-putting. Head retention is a weakness but that doesn't surprise me given the really long beta rest time and pretty much complete absense of alpha rest time.
If it was hoppier, it would make a heck of a Czech Pilsner. :)

PS...I almost always keep lagers below 5% and this one, at a solid 6.5%, definitely seems to have a happy juice component going for it. :)
 
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