M15 Empire Ale Yeast

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Some advice or input would be appreciated

I was thinking of using Empire Ale yeast, pitching two packs in a 12l batch of Imp stout. I'm mashing in at 65.5c I'm aiming for a SG of 1.102 and an FG of 1.022

Basically I'm re-brewing an Imp stout I made last year which was barrel aged but I never got to try the stout stand alone and we left it too long in the barrel so that the base beer didn't really come across - noob error on our part! I want to ferment this version in my All Rounder under pressured. The plan is to give it about a week at normal temps 18-20c then increasing the temperature and putting the spunding valve on - the idea is to capture the yeast character of the Empire Ale in that first week but I do want the beer to get down to the planned 1.020ish. I'm aiming for a SG of 1.102 and an FG of 1.022

I suppose instinct is saying ferment out with the Empire Ale for 2 weeks and maybe pitch the Nottingham if it's still got quite a high gravity? If M15 generally stops around the 1.020 mark then I'd be chuffed but pitching some Nottingham seems like a sure fire way to finish the beer off if it stalls high.

Any thoughts or advice on this plan? The recipe is below:

Butcher Imp Stout

Pale Ale Malt (53.1%)
Maris Otter (12.9%)
Oats, Flaked (8.5%)
Pale chocolate malt (7.4%)
Roasted Barley (6.4%)
Chocolate Malt (4.2%)
Caramel/Crystal Malt -120L (4.2%)
Caramel/Crystal Malt - 70L (2.2%)
Black Malt (1.0%)
 
Bear in mind M15 is really not that alcohol-tolerant, it only goes up to 8% or so. So it won't be taking a 1.102 wort much below 1.050!!

And if you're expecting a second yeast to ferment it the rest of the way, it's asking quite a lot of it to start once all the simple sugars have been exhausted, they need a bit just to get up and running. By the time you've bought two packs of dry yeast you might as well get a single pack of a liquid yeast that's much more alcohol-tolerant, like WLP540 (which despite allegedly coming from Rochefort is a British yeast), which will eat 1.102 without breaking a sweat.
 
Hi,

Empire Ale yeast tops out at 8% ABV and 75% attenuation. If you achieve your aims you end up with a beer at 10% and will need 80% attenuation. MJ yeasts always perform well but you may be asking too much here.

Their M42 New World Strong Ale yeast might be better, 82% attenuation and ABV tolerance of 12%.
 
Hi,

Empire Ale yeast tops out at 8% ABV and 75% attenuation. If you achieve your aims you end up with a beer at 10% and will need 80% attenuation. MJ yeasts always perform well but you may be asking too much here.

Their M42 New World Strong Ale yeast might be better, 82% attenuation and ABV tolerance of 12%.

I used the M42 in the original brew but was thinking the M15 might add a bit of character based on its description but I've totally overlooked the 8%ABV! D'oh!
I could add more water and make a slightly bigger batch, taking the ABV down a bit or maybe just go with an alternative yeast.

@Northern_Brewer
Just saw your comment cheers!
 
Empire Ale yeast does have a nice character although you and I might be in the minority here! Higher levels of alcohol though do mask much of that character so you might need to make a choice between an Impy (and use another yeast) or explore the character of M15 in a different beer - a brown ale would be a good choice maybe.
 
Empire Ale yeast does have a nice character although you and I might be in the minority here! Higher levels of alcohol though do mask much of that character so you might need to make a choice between an Impy (and use another yeast) or explore the character of M15 in a different beer - a brown ale would be a good choice maybe.

The description sounds interesting and I might alter the recipe to be less imperial and more big stout. I’ve been meaning to do a brown ale Janet’s Brown Ale has been on my radar so that might be an option?
 
I've used M15 twice and both times had massive overcarbonation issues. A porter which sprayed everywhere and a PB which blew the PRV during conditioning. I've not used it since
 
I've been able to grab some M42 for the brew day so I'll proceed as planned with that in place of M15. The M15 won't go to waste though and I'll see how it fare's maybe doing some split batches over the coming months on an Amber Ale, an Irish Rye Red and an Altbier!
 
I've got a brew in right now using M15 for the first time. I've previously had overcarbonation issues using M36 Liberty Bell so going to leave this batch in the fermenter for a slightly extended period (might be 3 weeks due to other commitments now anyway). Started at 1034 & down to 1009 after 3 days so hoping I'll be OK.
 
I've used this yeast twice recently and was puzzled (and disappointed) that it stopped at 1015 - 1020. The resulting bitter and stout bottles are 'gushers' that Red Adair would have had trouble with. There's no excessive gas initially, but as ssoon as it's poured, the foam is ..... well, it just is.
I'd fermented the brews for 2-3 weeks each and they had by all appearances stopped. The results are drinkable but cloudy (luckily they are dark anyway), it just takes 25 minutes to get a pint from the jugs that I have to pour it into! (By which time, the thrill is gone and the Staropramen is open).
 
I've done brews like this with two different yeasts. You need more anyway in a high ABV, so why not use two different strains? One for character, one for attenuation. Pitch M15, or Windsor or S-33, together with Nottingham. You could delay the Nottingham for 24 hours or so to let the character yeast get a head start. But don't leave it too long or the Notty will struggle to get a foothold.

I've read a couple accounts from people who have used M15 a few times who say it tends to have a week off. It stops fermenting. And then starts again. That would explain gushing bottles, and low OGs, if you bottle during its week's vacation. Make sure it's warm enough and give it time to finish. Patience necessary, it would seem.
 
My first time trying Lallemand London Ale yeast, in a London Porter - is behaving very like the descriptions of MJ M15 on this thread. OG 1058, and after several days vigorous fermentation, has gone to sleep on the job at 1022, somewhat above my target FG of 1014. Lallemand say that fermentation can be complete after three days, but I'll follow Clibit's advice I'll see what happens over the next week. Lallemand also say this yeast doesn't ferment Maltotriose, which makes up 10-15% of a typical wort, which would adjust the target FG to 1020. So maybe this is it! As for Darrellm's brew, the taste is spot on, so I'm not too disappointed!
 
Well...as per topic...I've done a fg on the porter and its stable at 1.020..although I thought it might have dropped a bit further . The thing is I've just prepped everything...washed and sanitised 50 bottles and all the gubbins to bottle...
It doesn't taste over sweet it's quite nice in fact! I was 4 points over OG to start and the predicted fg was 1.014,attenuation stands at 62%.
Can't hang about I shall crack on...
 
That's all bottled. Half way through I had a great idea....what I should have done was keg it in the empty pb I now have then it wouldn't have mattered if it got a bit busy as it would have vented. Ah well what's done and all that...I'll only leave it a week then try one...if there's any fizz they'll be put in the shed.
 
Well...as per topic...I've done a fg on the porter and its stable at 1.020..although I thought it might have dropped a bit further . The thing is I've just prepped everything...washed and sanitised 50 bottles and all the gubbins to bottle...
It doesn't taste over sweet it's quite nice in fact! I was 4 points over OG to start and the predicted fg was 1.014,attenuation stands at 62%.
Can't hang about I shall crack on...
Hey @Clint - this is Hazelwood's plum Porter recipe, right?

I've said this before and I'll say it again -though not to you nor in this thread 😉 - but I'll repeat it for the masses...

I think what you're seeing here (and @darrellm in his OP) is to be expected...

You've got 28% of low-to-no-fermentable dark malts (roasted grains, dark crystal etc)...

From experience I'm convinced brewing calculators (certainly Brewer's Friend that I use) massively over-predict how fermentable these dark malts are. They will add to the OG (flavour, body etc) but they don't contribute much/anything in the way of fermentables, hence you see a high FG.

(This is especially pronounced in lower ABV beers where the proportion of base malt is less. If you're making a stronger 6-7% ABV beer or higher it's less noticeable because the proportion of base malt is higher).

Combine that with a lower attenuating yeast like M15 and it compounds the situation (I note Hazelwood used US-05 originally which is one of the higher attenuating ale yeasts).

Personally I'm happy with my 3.5-4.0% ABV Stouts & Porters. I think you have enough experience to know if the beer tastes "done" and "good" or if something's up.

So if the beer is good I'd just go with it - if you want a stronger beer next time I'd suggest increase the base malt but leave the dark malts as they are (rough idea here how to estimate what the real FG and ABV will be).

Cheers,

Matt 👍🍻 :beer1:
 
Hey @Clint - this is Hazelwood's plum Porter recipe, right?

I've said this before and I'll say it again -though not to you nor in this thread 😉 - but I'll repeat it for the masses...

I think what you're seeing here (and @darrellm in his OP) is to be expected...

You've got 28% of low-to-no-fermentable dark malts (roasted grains, dark crystal etc)...

From experience I'm convinced brewing calculators (certainly Brewer's Friend that I use) massively over-predict how fermentable these dark malts are. They will add to the OG (flavour, body etc) but they don't contribute much/anything in the way of fermentables, hence you see a high FG.

(This is especially pronounced in lower ABV beers where the proportion of base malt is less. If you're making a stronger 6-7% ABV beer or higher it's less noticeable because the proportion of base malt is higher).

Combine that with a lower attenuating yeast like M15 and it compounds the situation (I note Hazelwood used US-05 originally which is one of the higher attenuating ale yeasts).

Personally I'm happy with my 3.5-4.0% ABV Stouts & Porters. I think you have enough experience to know if the beer tastes "done" and "good" or if something's up.

So if the beer is good I'd just go with it - if you want a stronger beer next time I'd suggest increase the base malt but leave the dark malts as they are (rough idea here how to estimate what the real FG and ABV will be).

Cheers,

Matt 👍🍻 :beer1:
Yes,I agree. Beer tasted good and is now resting in the carbonation chamber (living room with throw over). I think H's recipe may have had some added sugar but I left that out as it would have been stronger than I wanted but may have helped the fg.
 
After starting this thread nearly a year ago, I decided to give M15 one last go: mashed mid-range 64C and temperature-controlled ferment at 19C. It has confirmed my suspicions, this yeast has a very long tail to the end of the ferment. The 2-week rule definitely does not apply with this one, this is it on Day21 it still has a Krausen! And this time is has fermented right down, after giving it long enough in the FV. Yeast attenuation is currently 78% which is higher than expected, just hope some nasties haven't gotten in there.
IMG_1366.JPG
 
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@darrellm : Other equivalent yeasts from other suppliers seem to have the same problem.

My hypothesis is that this is because this yeast is the offspring of the yeasts from the 19th century which were used in casks. That it ferments slowly further was an advantage. After the beer dropped clear in the cask (not only pub casks, but also household casks), fermenting slowly further would keep the beer longer fresh.
 

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