Dry yeasts identified - your opinions please!

[duncan_disorderly]

My take on MJ yeasts...

M12 Kveik Voss - Lallemand Voss
M15 Empire - Windsor
M20 Bavarian Wheat - Lallemand Danstar Munich? Pure guess, never used Munich
M21 Belgian Wit - not used it.
M29 French Saison - Belle Saison probably.
M31 Belgian Tripel - is a blend
M36 Liberty Bell - Notty + Windsor?
M41 Belgian Ale - not used it
M42 New World - Nottingham.
M44 West Coast - Lallemand Bry-97
M47 Belgian Abbey - not used it yet. Lallemand Abbaye?
M54 Cali Lager - possibly Mauribrew Lager? Not tart like K-97 is described.
M76 Bav Lager - sacch + pastorianus acc to MJ website (sacch + Diamond?)
M84 Boho Lager - is a sacch strain acc to MJ website.

 

[duncan_disorderly]

However, I'm sure I definitely taste a difference between the original Fermentis yeasts and their repacked Mangrove Jack's versions. Almost all of Fermentis originals, pitched dry, are noticeably tarter than their MJ repacks. I don't know why. And I think MJ's versions are much better, to be honest. I prefer them to Fermentis.

If they were repacked they wouldn't be different, surely. I believe they are not Fermentis. That's the simple explanation. I've used a lot of the dry yeasts from Lallemand, Fermentis and MJ and I don't see equivalences between Fermentis and MJ, from my own experience. I think they are mostly Lallemand, including blends and enzymes. Nutrients perhaps. I could be wrong, of course. Just trying to add my experience to the debate.

 

[Protos]

Well, that's possible. Then again, I wouldn't say most MJ yeasts are much closer to their Lallemand's counterparts rather than to Fermentis' ones (except, perhaps, Nott and Kveik).
M20 and Classic Munich, for example, are quite different, Belle is less 'juicy' than M29, M15 is fruitier than Windsor, and so on.
Whichver producer they repack (I believe both, and even probably some other) no MJ yeast tastes to me exactly the same as its supposed counterpart in Fermentis or Lallemand range. Sometimes close, but never exactly the same. Which still leaves a question: what MJ do to their repacked yeasts to get that effect?

 

[dmtaylor]

M84 Boho Lager - is a sacch strain acc to MJ website.

Everything (or dang near) is Saccharomyces. The different species are generally between pastorianus vs. cerevisiae -- perhaps that is what you meant?

But from what I can tell, MJ is still reporting M84 as "bottom-fermenting lager".

https://mangrovejacks.com/products/m84-bohemian-lager-10g

 

[duncan_disorderly]

Well, that's possible. Then again, I wouldn't say most MJ yeasts are much closer to their Lallemand's counterparts rather than to Fermentis' ones (except, perhaps, Nott and Kveik).
M20 and Classic Munich, for example, are quite different, Belle is less 'juicy' than M29, M15 is fruitier than Windsor, and so on.
Whichver producer they repack (I believe both, and even probably some other) no MJ yeast tastes to me exactly the same as its supposed counterpart in Fermentis or Lallemand range. Sometimes close, but never exactly the same. Which still leaves a question: what MJ do to their repacked yeasts to get that effect?

That's a good question, but I do believe the MJ range is much closer to the Lallemand range than Fermentis. Just based on my taste buds and batches I've brewed. I think MJ tinkers with a few though.

 

[duncan_disorderly]

Everything (or dang near) is Saccharomyces. The different species are generally between pastorianus vs. cerevisiae -- perhaps that is what you meant?

But from what I can tell, MJ is still reporting M84 as "bottom-fermenting lager".

https://mangrovejacks.com/products/m84-bohemian-lager-10g

Yes cerevisiae sorry.

https://help.mangrovejacks.com/hc/en-us/articles/360019268213-What-species-of-yeast-do-you-use-

 

[dmtaylor]

https://help.mangrovejacks.com/hc/en-us/articles/360019268213-What-species-of-yeast-do-you-use-

Ugh. Looks like MJ is about as inconsistent and untimely with updating their documentation as all the other manufacturers.

So it's really anybody's guess, until we can get these MJ strains tested.

 

[BrewnWKopperKat]

@CascadesBrewer have you seen/listened to the occasional Basic Brewing Radio episodes where people talk about brewing split batches with different yeast strains? From the show notes, there are a couple of episodes where they talk about split batches with dry yeast.

Also, if there are people are going to give this a try and are willing to share their base recipe, it would be possible for others to brew along, compare notes, etc.

 

[Protos]

Looks like MJ is about as inconsistent and untimely with updating their documentation

I have three their yeast catalogues: v.1, v.3 and v.9, and M76 is listed firstly as cerevisiae then as cerevisiae+pastorianus, and M84 shown as cerevisiae throughout. And yes, both "are bottom-fermented lager yeasts". It seems MJ stick rather to German (rather than American Craft) terminological tradition, where Lager is anything that's lagered, whatever the yeast species.

 

[CascadesBrewer]

Also, if there are people are going to give this a try and are willing to share their base recipe, it would be possible for others to brew along, compare notes, etc.

I am not sure I am that organized! I will often brew 5 gallons of wort and split that into two fermenters. I just recently brewed 3 gallons of a Saison recipe and split them with WLP565, Belle Saison, and Omega Voss. That batch is bottle conditioning now. I have a Tripel fermenting with M31 Tripel Ale (not split) checking if that is more of a Trappist style yeast or a Saison.

I will probably be another month or two before I do another round. I will probably brew a simple Belgian-ish recipe (something like a 5% Single) and throw a number of Belgian-ish yeasts.

 

[Protos]

M31 is supposed to be a Saison and is listed as close to BE-134 in the spreadsheet. And it behaves much like a Saison yeast. But I've never tasted anything Saisony from it. In my experience, it's a fine Trappist-style yeast, much closer to M41 than to M29 or BE-134. Recently I used it in a Karmeliet Tripel recipe from 1679, and I love the beer. Very good yeast.

 

[dmtaylor]

M31 is supposed to be a Saison and is listed as close to BE-134 in the spreadsheet. And it behaves much like a Saison yeast. But I've never tasted anything Saisony from it. In my experience, it's a fine Trappist-style yeast, much closer to M41 than to M29 or BE-134. Recently I used it in a Karmeliet Tripel recipe from 1679, and I love the beer. Very good yeast.

Thanks for the recipe and experience... But how did it TASTE??

 

[Northern_Brewer]

M20 Bavarian Wheat - Lallemand Danstar Munich? Pure guess, never used Munich
M21 Belgian Wit - not used it.
M29 French Saison - Belle Saison probably.

No probably about M29 and Belle, they are the same.

Given that Munich is meant to have less character than Munich Classic, and Munich is now sold as a wit yeast, without any direct experience I'd assume M20 was Munich Classic and M21 is Munich/Wit.

MJ may have the odd Fermentis but they definitely seem to mainly map to Lallemand. I saw something where they said they try to have two options in most categories, which explains why they eg have so many lager yeasts.

If I was white-labelling yeasts, I'd be putting 10% Notty into most of them just to make them stick. Maybe less important for US market, but definitely for UK market where conditioning in bottles and pressure kegs is the norm.

 

[duncan_disorderly]

No probably about M29 and Belle, they are the same.

Given that Munich is meant to have less character than Munich Classic, and Munich is now sold as a wit yeast, without any direct experience I'd assume M20 was Munich Classic and M21 is Munich/Wit.

MJ may have the odd Fermentis but they definitely seem to mainly map to Lallemand. I saw something where they said they try to have two options in most categories, which explains why they eg have so many lager yeasts.

If I was white-labelling yeasts, I'd be putting 10% Notty into most of them just to make them stick. Maybe less important for US market, but definitely for UK market where conditioning in bottles and pressure kegs is the norm.

M20 doesn't have a huge amount of character, if it's Munich Classic I would imagine it's a diluted version.

If MJ has any Fermentis I've yet to come across one that has tasted like one. Not tasted them all yet though. I've tasted M15, M20, M29, M31, M36, M41, M42, M44, M54 and M76. I don't believe any of those are Fermentis. Unless they've been tampered with/blended or something.

 

[dmtaylor]

M20 doesn't have a huge amount of character, if it's Munich Classic I would imagine it's a diluted version.

If MJ has any Fermentis I've yet to come across one that has tasted like one. Not tasted them all yet though. I've tasted M15, M20, M29, M31, M36, M41, M42, M44, M54 and M76. I don't believe any of those are Fermentis. Unless they've been tampered with/blended or something.

Methinks M20 is actually Mauri Weiss, and neither of which are the same as Munich Classic.

I would further challenge you (or anyone else) to think about what the equivalents might be for the following MJ yeasts, which don't seem to have good options from Lallemand:

M31 Tripel (likely BE-134 or WB-06, at least in part)
M47 Abbey (ditto)
M41 Belgian (BE-256?)
M36 Liberty (S-04 or US-05)
M84 Bohemian (S-23 or W-34/70)

If Lallemand is making equivalents of any of these, I haven't seen them, except maybe for their Abbaye and brand-new Farmhouse strains. Even then, their actual apparent attenuations probably mismatch. And if you think you've found great matches, then feel free to provide your objectively verifiable reasoning why/how.

I think MJ gets quite a good bit of their yeast from Fermentis, or otherwise they might indeed be concocting some pretty interesting mixtures on their own, for which to date, many including myself haven't yet given them enough credit. My guess leans towards... they probably use some Fermentis... regardless of whether Fermentis knows or cares. But I can only guess.

 

[kmarkstevens]

Also, if there are people are going to give this a try and are willing to share their base recipe, it would be possible for others to brew along, compare notes, etc.

FYI, I do spilt batches quite a bit at random intervals. I've got too many yeasties in my bank and want to thin the herd, so have been doing blind yeast offs and discarding a few.

Most folks use a simple SMASHY recipe. You might want to consider that yeasts behave differently with different adjuncts as well. I did an English porter yeast off and was gob smacked to discover one yeast had chocolate notes (S-04) and the other yeast (WLP085) had none. If it had been a simple SMASH recipe, I would have completely missed that. So, in my humble opinion, not only is it yeast vs yeast, but even yeast vs yeast per style.

And you can blend yeasts. For example, I really like S-04 (whitbread dry) & WLP017 (one of the whitbread liquid multi strains) blended. To my palate and that of the local HBS, the blend was superior. White Labs has a Guide To Blending Yeast Strains.

@dmtaylor Love your hobby, and that you are actually verifying (as much as possible) the different strains. There are tons of interweb sites that simply repeat some WAG from a few decades ago. But you have carefully vetted and curated a dang impressive list.

I have one that might pass your muster. WLP085 is a blend of WLP002 and something else, most likely speculation has it as WLP006 or WLP007. I've emailed and asked the San Diego bartender (who didn't really know his yeast) and got the "can't disclose" answer. Well, the example used in White Labs Guide To Blending Yeast Strains slide 8 Goal 2: Improving Yeast Performance uses WLP002 and WLP007 as the second example. Absent Chris White spilling the beans, I submit this is confirmation, but it's your spreadsheet.

 

[Miraculix]

FYI, I do spilt batches quite a bit at random intervals. I've got too many yeasties in my bank and want to thin the herd, so have been doing blind yeast offs and discarding a few.

Most folks use a simple SMASHY recipe. You might want to consider that yeasts behave differently with different adjuncts as well. I did an English porter yeast off and was gob smacked to discover one yeast had chocolate notes (S-04) and the other yeast (WLP085) had none. If it had been a simple SMASH recipe, I would have completely missed that. So, in my humble opinion, not only is it yeast vs yeast, but even yeast vs yeast per style.

And you can blend yeasts. For example, I really like S-04 (whitbread dry) & WLP017 (one of the whitbread liquid multi strains) blended. To my palate and that of the local HBS, the blend was superior. White Labs has a Guide To Blending Yeast Strains.

@dmtaylor Love your hobby, and that you are actually verifying (as much as possible) the different strains. There are tons of interweb sites that simply repeat some WAG from a few decades ago. But you have carefully vetted and curated a dang impressive list.

I have one that might pass your muster. WLP085 is a blend of WLP002 and something else, most likely speculation has it as WLP006 or WLP007. I've emailed and asked the San Diego bartender (who didn't really know his yeast) and got the "can't disclose" answer. Well, the example used in White Labs Guide To Blending Yeast Strains slide 8 Goal 2: Improving Yeast Performance uses WLP002 and WLP007 as the second example. Absent Chris White spilling the beans, I submit this is confirmation, but it's your spreadsheet.

Just to 2nd what you wrote about s04, I really don't like this yeast in a pale beer. But in a stout, it is truly marvelous and has yet to find it's true competitor in my dark beers. I cannot say why, but it does stuff. And this stuff is really good in dark beers.

Recently, I've been imagining a dragon stout clone-ish type of beer with it. The fruitiness will fit perfectly.

 

[duncan_disorderly]

Methinks M20 is actually Mauri Weiss, and neither of which are the same as Munich Classic.

I would further challenge you (or anyone else) to think about what the equivalents might be for the following MJ yeasts, which don't seem to have good options from Lallemand:

M31 Tripel (likely BE-134 or WB-06, at least in part)
M47 Abbey (ditto)
M41 Belgian (BE-256?)
M36 Liberty (S-04 or US-05)
M84 Bohemian (S-23 or W-34/70)

If Lallemand is making equivalents of any of these, I haven't seen them, except maybe for their Abbaye and brand-new Farmhouse strains. Even then, their actual apparent attenuations probably mismatch. And if you think you've found great matches, then feel free to provide your objectively verifiable reasoning why/how.

I think MJ gets quite a good bit of their yeast from Fermentis, or otherwise they might indeed be concocting some pretty interesting mixtures on their own, for which to date, many including myself haven't yet given them enough credit. My guess leans towards... they probably use some Fermentis... regardless of whether Fermentis knows or cares. But I can only guess.

M31 is a blend. I don't know what.
M36 is neither S04 nor US-05 in my opinion. I've used it quite a lot. My guess is a blend Notty/Windsor. I've seen firm and powdery sediment, and the character of the beers seemed right. And Notty/Windsor is a common blend in the UK.
M41 - likely a blend, similar to M31
M47 - not used it yet, have a pack.
M84 - not used it.

They may use some Fermentis, Ive just yet to try anything that convinced me. Whereas M42 must be Nottingham, M44 must be Bry-97. M36 and S04 are different. Is there any single MJ yeast which anybody could confidently say is Fermentis? And I doubt they could use the quantities they'd need without Fermentis knowing.

I've used M20 and MB Weiss a few times each. They seemed different to me.

 

[Kold Brygg]

My guess is that the picture is more complicated. There are more yeast producers than Fermentis, Lallemand and Mauribrew.

CrossMyLoof are rumoured to have some of their yeasts from Germany, I think @Northern_Brewer provided this information. There is a Swedish company producing beer yeast. I've been in touch with them, when asking about beer yeast, they say they produce on behalf of AEB. AEB says they don't produce yeast for others than AEB.

The AEB yeasts are very similar to Fermentis yeasts. So even if they seems very similar it seems unlikely they get them from Fermentis. Why should AEB get yeast from Fermentis, when they have a another factory producing them? This might be case for other brands also.

I find @dmtaylor 's spreadsheet very useful, some of his connections might not be accurate, but it gives an clear indication, in most cases that's what I need. And I like the colours. If you consider changing, I hope you at least keep the ones confirmed one way or another.

 

[duncan_disorderly]

DMT's spreadsheet is really useful, it shows similar yeasts across different suppliers, wet and dry.

The MJ rep I spoke to said they repackage some strains and have some "produced for them", but he was very wary, didn't want to tell me anything. I think MJ packages stuff in England and tests out blends and additions to tweak existing dry strains to provide some improved/different options. So I don't think many MJ packages are exactly the same as anything else. Not sure how many though. M42 and M44 seem obvious.

 

[Silver_Is_Money]

I'm all for yeasts no longer being referred to as 'ale' or 'lager' varieties, mainly because the word 'lager' to me means prolonged cold storage, and in my opinion it does not have defined meaning related to yeast. In my opinion yeasts should simply be marketed as being suitable for cold fermenting, warm fermenting, very warm fermenting (for example, the Kveik's), or multi-purpose cold/warm temperature range fermenting (examples: W-34/70, Nottingham). They should also be marketed as to their characteristic flavor related traits, such as (in broad terms) clean, estery, etc...

 

[dmtaylor]

I'm all for yeasts no longer being referred to as 'ale' or 'lager' varieties, mainly because the word 'lager' to me means prolonged cold storage, and in my opinion it does not have defined meaning related to fermentation. In my opinion yeasts should simply be marketed as being suitable for cold fermenting, warm fermenting, very warm fermenting (for example, the Kveik's), or multi-purpose cold/warm temperature range fermenting (examples: W-34/70, Nottingham). They should also be marketed as to their characteristic flavor related traits, such as (in broad terms) clean, estery, etc...

The older I get... the definitions of "ale" vs. "lager" to me should be based mostly on taste, not process or yeast species. To me, "lager" means the beer doesn't taste like anything but malt and hops. THAT'S a "lager". I don't care how it was made. If it tastes like a lager, it's a lager. Anything else is an ale.

I just used S-189 and S-23 to make a few batches of "lager"... but I fermented them warm at 68 F (20 C). I swear I got much better (and faster!) results at this temperature than when I tried fermenting colder. No one needs to know that I fermented them warm. If it tastes like lager, I'm calling it a lager.

Also I recently made an attempt at a fruity interesting Aussie Spockling Ale, using S-04, again at high temperature, I think it was around 70 F (21 C). BUT IT TURNED OUT CLEAN AS A WHISTLE, like a LAGER. So again.... instead of calling it an ale at all, it tasted like a "lager", so I called it a lager! Not fruity at all. Quite delicious, actually.

Again I say, to anyone who disses S-04.... I implore you to give it another try. And maybe ferment it at 70 F / 21 C.

And for that matter... try S-189, S-23, W-34/70, etc. AT ROOM TEMPERATURE and see what YOU think! Lager?!

If it tastes like a lager, it's a friggin lager.

[/soapbox]

P.S. The cleanest way to classify yeasts, on the other hand, should truly be "cerevisiae" vs. "pastorianus". To those who sell yeasts, I wish they'd use these terms instead of "bottom-fermenting" or "from Munich" (which really tells me not a damn thing!) or whatever.

P.P.S. And throw the temperature recommendations out the window!!!! Let US decide what temperatures we want to try! If you know me at all, you know I'll be fermenting dang near everything warm, room temperature, from here on out, regardless of whether it's a "lager". Or maybe vice-versa, make more "ales" at cooler temperatures to see what that does. Experimentation is so much fun. Split every batch and do something weird. Learn so much.

Cheers!

 

[duncan_disorderly]

The older I get... the definitions of "ale" vs. "lager" to me should be based mostly on taste, not process or yeast species. To me, "lager" means the beer doesn't taste like anything but malt and hops. THAT'S a "lager". I don't care how it was made. If it tastes like a lager, it's a lager. Anything else is an ale.

I just used S-189 and S-23 to make a few batches of "lager"... but I fermented them warm at 68 F (20 C). I swear I got much better (and faster!) results at this temperature than when I tried fermenting colder. No one needs to know that I fermented them warm. If it tastes like lager, I'm calling it a lager.

Also I recently made an attempt at a fruity interesting Aussie Spockling Ale, using S-04, again at high temperature, I think it was around 70 F (21 C). BUT IT TURNED OUT CLEAN AS A WHISTLE, like a LAGER. So again.... instead of calling it an ale at all, it tasted like a "lager", so I called it a lager! Not fruity at all. Quite delicious, actually.

Again I say, to anyone who disses S-04.... I implore you to give it another try. And maybe ferment it at 70 F / 21 C.

And for that matter... try S-189, S-23, W-34/70, etc. AT ROOM TEMPERATURE and see what YOU think! Lager?!

If it tastes like a lager, it's a friggin lager.

[/soapbox]

The cleanest way to classify yeasts, on the other hand, should truly be "cerevisiae" vs. "pastorianus". To those who sell yeasts, I wish they'd use these terms instead of "bottom-fermenting" or "from Munich" (which really tells me not a damn thing!) or whatever.

And throw the temperature recommendations out the window!!!! Let US decide what temperatures we want to try! If you know me at all, you know I'll be fermenting dang near everything warm, room temperature, from here on out, regardless of whether it's a "lager". Or maybe vice-versa, make more "ales" at cooler temperatures to see what that does. Experimentation is so much fun. Split every batch and do something weird. Learn so much.

Cheers!

I ask people what they think my beers are. If they think it's a lager, then that's all that matters, to them.

I've got a pack of S04. Not used S04 for a while. Any suggestions?! Should I make a starter, as I think Protos suggested, to remove/diminish the tartness?

 

[dmtaylor]

I've got a pack of S04. Not used S04 for a while. Any suggestions?! Should I make a starter, as I think Protos suggested, to remove/diminish the tartness?

I didn't find it tart at all, or bready or doughy or anything like that. I was just as shocked as anybody. I suggest trying to make/duplicate a Bohemian "lager" with it. Do NOT need to make a starter, just sprinkle it in (I never make a starter with dry yeast). But ferment warm, 70-72 F (21-22 C). If I'm wrong, call it an Aussie Spockling Ale or British Golden Ale. But what if I'm right? I'd be very curious to hear results back if you or anybody else tries this. I'm intrigued, because the last two beers I made with S-04 both turned out like this -- clean and malty.

 

[duncan_disorderly]

I didn't find it tart at all, or bready or doughy or anything like that. I was just as shocked as anybody. I suggest trying to make/duplicate a Bohemian "lager" with it. Do NOT need to make a starter, just sprinkle it in (I never make a starter with dry yeast). But ferment warm, 70-72 F (21-22 C). If I'm wrong, call it an Aussie Spockling Ale or British Golden Ale. But what if I'm right? I'd be very curious to hear results back if you or anybody else tries this. I'm intrigued, because the last two beers I made with S-04 both turned out like this -- clean and malty.

I'd be surprised to get a lager from S-04, but I may have to try it! I've definitely got tart/doughy from S-04, but we all taste things differently. Which makes all this comparison stuff rather difficult really, when it comes to comparing notes. It's all a personal thing, really, I guess. We have to taste things for ourselves and reach our own conclusions.

 

[Miraculix]

I think they changed something. Newer reports differ 100% from what I got from this yeast months and years ago.

 

[Protos]

Thanks for the recipe and experience... But how did it TASTE??

Well, in my experience recreated ancient beers rarely taste well. Not that they are bad, just too exotic and unfamiliar to my taste (kuits, gruits, sahtis, raw kveiks and various medieval recreations - I brewed quite a few of them and liked much fewer). The 1679 Karmeliet Tripel is a gem. I used oat malt instead of spelt. M31 worked like a charm: it gave the beer a bit of glycerol sleekness (same as with M29), pleasant yeast bite (like M41) and a slightest hint of fruitiness (close to M47 but weaker, sweeter and less phenolic). It's more about mouthfeel rather than flavours. Pilsner sweetness, Wheat graininess and Oat floral notes imtermarry perfectly on that background (idk if that's just my perception, oat malts always taste perfumey to me, over 15% it becomes unpleasant, that's why I didn't like my kuits).
My Tripel is a bit young (just 2 months in bottle, while my other M31 tripels usually required at least half a year to reach their prime), still it's already a very good beer. I highly recommend both the recipe and the yeast if you want to brew a solid Tripel.

 

[Kold Brygg]

I ask people what they think my beers are. If they think it's a lager, then that's all that matters, to them.

I've got a pack of S04. Not used S04 for a while. Any suggestions?! Should I make a starter, as I think Protos suggested, to remove/diminish the tartness?

Old School Golden Ale.
British Grain, Hops and yeast. Just like it was when Golden Ales started.
https://www.homebrewtalk.com/threads/summer-lightning-clone.693874/

 

[duncan_disorderly]

Old School Golden Ale.
British Grain, Hops and yeast. Just like it was when Golden Ales started.
https://www.homebrewtalk.com/threads/summer-lightning-clone.693874/

I drank golden ales in England before Summer Lightning, I believe. I've never understood the idea that it was the first golden ale. But it possibly depends on your definition. I think that was just a marketing moment, looking for a way to attract new drinkers to something that already existed. I see golden ale as a pale bitter, rightly or wrongly, and those have been around a long time, certainly here in the north of England. Roger Protz goes back further...

https://protzonbeer.co.uk/features/2014/05/02/golden-ale-beer-style-that-s-a-golden-oldie

 

[BrewnWKopperKat]

reply #280 (link) has some recent discussion on tartness in S-04.

Others have recently mentioned that people taste things differently (so there's not need for me to repeat that here ).

I've got a pack of S04. Not used S04 for a while. Any suggestions?! Should I make a starter, as I think Protos suggested, to remove/diminish the tartness?

Personally, I'd skip the starter for the 1st batch and see if I actually taste the tartness. So maybe a "split batch" with a different strain of yeast. Or maybe a split batch fermented at different temperatures.