London Ale III 86% Attenuation

[Bowie92]

Hi all,

First post here so nice to meet you all.

I've used London Ale III for the first time on a juicy pale ale and I've ended up with a whopping 86% attenuation with the beer drying out to 1.005. This is significantly higher than advertised and a bit annoying as it was meant to be a session strength beer and I wanted a bit of residual sweetness/body.

Has anyone experienced this before with this yeast and any ideas why this happened?

Some more information:

• First gen yeast from a starter
• Grain bill was 75% Extra Pale, 10% Torrefied Wheat, 7.5% Flaked Oats, 7.5% Carapils
• Mashed at 65C (149f) for 90 minutes
• I don't have temperature control for fermentation but it was approx 21C (70F)

Thanks!

 

[dmtaylor]

Most hops contain enzymes. When you dry hop and experience crazy high attenuation like this, you are most likely experiencing the phenomenon known as "hop creep" where these enzymes are restarting the fermentation and drying out the beer more than you intended. It's happened to millions of brewers everywhere.

Secondly I think you mashed too long at 90 minutes. I only mash for 45 minutes usually or 60 at most. YMMV.

 

[Bowie92]

Most hops contain enzymes. When you dry hop and experience crazy high attenuation like this, you are most likely experiencing the phenomenon known as "hop creep" where these enzymes are restarting the fermentation and drying out the beer more than you intended. It's happened to millions of brewers everywhere.

Secondly I think you mashed too long at 90 minutes. I only mash for 45 minutes usually or 60 at most. YMMV.

That would make sense. How much extra attenuation/gravity points drop would you generally expect with this? I guess it would make sense to mash a bit higher in that case to account for that?

I normally mash for 90 minutes as it eeks out a little higher efficiency.

 

[dmtaylor]

That would make sense. How much extra attenuation/gravity points drop would you generally expect with this? I guess it would make sense to mash a bit higher in that case to account for that?

I normally mash for 90 minutes as it eeks out a little higher efficiency.

Based on much experimentation, mashing less time barely has any effect on efficiency IF the crush on your grains is really good (as mine is). With a less than great crush, you will see greater impact on efficiency from mash time fluctuations.

You can expect perhaps ~5% lower attenuation from a mash as short as 40-45 minutes in my experience, which in my view, I don't really care about attenuation, but when attenuation is way too high like yours, it might help, maybe. Of course I don't dry hop very often either. The hop enzymes might still take action regardless of the mash regimen, I'm not sure on that, and I know each hop variety and even each different crop year, terrior, etc. make a difference with the effectiveness of hop enzymes or lack thereof.

Tons of variables to fiddle around with, for anyone who is interested to do so.

 

[Toxxyc]

I've just learned about "hop creep". Thanks for that. It'll explain over-carbonation in a beer I made a while back.

 

[Genuine]

Also, you did mash at 149, you definitely pulled out more fermentable sugars. If you mashed higher at 154-156, you would have a higher finishing gravity. I would mash at 148 or 149 to have the beer finish out dryer in the single digit gravity points. Mash higher next time and I think you'll be pleasantly surprised. You may also be surprised that besides alcohol content, you may not notice much of a difference. I had a beer finish at 1.023 recently and people who tasted it thought it was dry and crisp without knowing the final gravity.

 

[IslandLizard]

Yup, ^
Mash your session beers higher, you want those dextrins. I usually mash those at 154-156F.
I mashed a 3% Oat Mild at 160-162F once. That's about the limit.

And a big "Welcome to HBT!"

 

[Bobby_M]

Just to prop the already good answers, attenuation is an estimated range and you mashed too low for a NEIPA. I mash mine at 156-158 to keep the FG around 1.018 to 1.021. This makes for a good mouthfeel to support the crazy hops without needing lactose. For your dry beer, just make a quick syrup from 8oz of Maltodextrine and you'll be all good.

I'm also not crazy about the NEIPA yeasts fermented that warm either. I prefer 65F for the 5-7 days, then 68. To be clear, an ambient room at 70F means beer fermenting at 75.

 

[Bowie92]

Thanks for the replies all. Think I've got an answer. Mashed too low and hop creep. Will keep those in mind next time!