WLP833 low attenuation

[strange-steve]

I brewed a Munich dunkel with this yeast a couple of weeks ago, checked the gravity a few days ago and it was at 1.020 from 1.055, only 64% attenuation. At that point it had been at 19°c for 5 days and should have been pretty much finished. So I gently roused the yeast and still at 1.020 today.

Anyone else have any experience with this yeast?

Mash schedule was taken from Braukaiser:
55c for 15 min
67c for 45 min
72c for 15 min
77c for 10 min.

Recipe was 98% Munich malt, 2% Carafa. Any thoughts are appreciated.

 

[strange-steve]

From a quick Google it appears that some others have noticed a lower than expected attenuation when using ~100% Munich malt. This is my first time using so much Munich, I'm wondering if that's what's going on...
Edit to add: Brulosophy saw a difference of 7 points in the FG of a Vienna malt beer and a Munich malt beer mashed at the same temperature.

 

[Sadfield]

A combination of low attenuating yeast struggling with extra dextrins from the Hochkurz mash and from the miallard reactions in the Munich malting.

What's the plan now, us05 to complete?

 

[strange-steve]

Thanks for that :hat:
Wierd that neither Jamil nor Braukaiser (whose recipes I copied for this) mentioned such a possibility, both show around 75% attenuation.
Yeah probably chuck a pack of US-05 in. It's a right pain in the balls, I really needed to get this bottled by next Wed at the latest for an upcoming competition

 

[Sadfield]

That's interesting, 75% attenuation is the upper limit of what White Labs suggest for that yeast, which one would assume was based on a pale malt grist and single infusion mash and be slighty more fermentable. Although I'd probably take more stock from Jamil and the Kaisers work than my musings.

I'm presume you are using German Munich malt, not British?

Could just be a yeast viability issue.

 

[BeerCat]

I suspect its a combination of a high mash temp and all that Munich. When i do a Hochkurz i skip the protein rest and do 45m at 62c and 68c then mashout. Even skip the 68c. I have got up to 85% attenuation doing this, other yeasts though. As a side note i have not come across many 100% grain bills but i know people do them. I have done some 100% Vienna but prefer the lighter malts.

 

[strange-steve]

I'm presume you are using German Munich malt, not British?

Could just be a yeast viability issue.

Yep Weyermann Munich. Could be viability, though it was a relatively fresh vial with a big starter which behaved as expected. I'm actually tempted to leave it as is, it doesn't taste overly sweet surprisingly. It'd be interesting to see if the BJCP judges pick up on it.

 

[strange-steve]

I suspect its a combination of a high mash temp and all that Munich. When i do a Hochkurz i skip the protein rest and do 45m at 62c and 68c then mashout. Even skip the 68c. I have got up to 85% attenuation doing this, other yeasts though. As a side note i have not come across many 100% grain bills but i know people do them. I have done some 100% Vienna but prefer the lighter malts.

Tbh I didn't want it to finish all that low, I was hoping for an FG of 1.015 so I'm 5 points high. Hadn't considered before that Munich malt might be less fermentable.

 

[Sadfield]

Yep Weyermann Munich. Could be viability, though it was a relatively fresh vial with a big starter which behaved as expected. I'm actually tempted to leave it as is, it doesn't taste overly sweet surprisingly. It'd be interesting to see if the BJCP judges pick up on it.

I love Munich for that deep roasty malt flavour, over the sweetness of crystal. Good luck in the comp.

I think Munich is around half the enzymatic power of base malt, so perhaps requires a little more time on your setup, compared to Jamils. So many variables in the mash to consider, such as grist thickness. I wonder if a static mash vs a recirculating makes a difference at the conversion stage?

 

[strange-steve]

Well I left this as it was and bottled it today. I suspect it will be dinged a few points in the competition for being too sweet, but otherwise I think the flavours are pretty good, lovely and toasty.

 

[Hanglow]

Munich is indeed less fermentable than pils for example, it will also drop your mash ph by more which may have an effect

 

[strange-steve]

Munich is indeed less fermentable than pils for example, it will also drop your mash ph by more which may have an effect

Interesting that you say that about pH, I had expected as such so increased alkalinity to give a predicted mash pH of 5.4 (from two different calculators) but I measured it at 5.7 for some reason, which is a big difference.

 

[BeerCat]

I normally use 3% acid malt on all my lagers. Although i cant double check the brewing software as i do not have a meter i am pretty sure i am getting better lacing/he

 

[strange-steve]

I normally use 3% acid malt on all my lagers. Although i cant double check the brewing software as i do not have a meter i am pretty sure i am getting better lacing/he

Are you still using 100% RO water? If so then a grain bill of pilsner malt, 3% acid malt plus a little calcium chloride I would guess would probably give you a mash pH of about 5.4 which is spot on :thumba:

 

[Hanglow]

I only just noticed your water treatment posts so I guess you know your stuff


5.7 is pretty high if you thought it would go to 5.4. would affect beta amylase negatively , so that combined with no beta rest in the mash could be the reason?.


Weyermann are supposed to have a qr code on their sacks you can scan and it will give you a link to that malt lot analysis, not sure if that would help if you have it. I always buy smaller amounts of their grain so have never checked it.

 

[BeerCat]

Are you still using 100% RO water? If so then a grain bill of pilsner malt, 3% acid malt plus a little calcium chloride I would guess would probably give you a mash pH of about 5.4 which is spot on :thumba:

Exactly as above Steve. Your water thread really helped me. Cheers

 

[JonBrew]

Well I left this as it was and bottled it today. I suspect it will be dinged a few points in the competition for being too sweet, but otherwise I think the flavours are pretty good, lovely and toasty.

If anything I think those 7 or so extra gravity points could set you apart in the competition in a good way. It's more likely to be perceived as a richer malt character rather than sweetness - just what you want from a Munich Dunkel (in my opinion).

 

[strange-steve]

I always buy smaller amounts of their grain so have never checked it.

Me too unfortunately.

If anything I think those 7 or so extra gravity points could set you apart in the competition in a good way. It's more likely to be perceived as a richer malt character rather than sweetness - just what you want from a Munich Dunkel (in my opinion).

I hope so, I'll report back in a few weeks with the score unless it scores 15 in which case I'll "forget" to.

 

[JonBrew]

Me too unfortunately.


I hope so, I'll report back in a few weeks with the score unless it scores 15 in which case I'll "forget" to.

Best of luck!

 

[strange-steve]

Well I'm dropping this off for the competition tomorrow (along with a few others) so having a very premature tasting after only 3 days in the bottle. It's mostly carbonated anyway and I'm actually rather pleased with it, not really too sweet at all and tons of rich maltiness.