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Diastaticus in Belgian Yeast

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ncbrewer

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I would like to avoid using any yeast containing diastaticus because of the potential for gushers or bottle bombs. I was interested in some of the Mangrove Jack's Belgian yeasts, but I couldn't find any info about it on the their website, so I emailed and asked. The answer was “To the best of our knowledge and testing, none of our yeast contain diastaticus”. Certainly the Mangrove Jack's company is the ultimate authority on their yeast, but I thought it was commonly agreed that many Belgian yeasts contain diastaticus. Any thoughts?
 
I looked on White Labs site and they say the same. I think their both full of s@#$. Look on Lalamades and Fermentis's sites and as they map them the description changes. TYB also states Diastaticus on most of the Belgians. I look at the ADF percentages and when stated between 83% and 90% i just assume it has it. Note TBY is MFG at White Labs!
 
It's typically the Saison strains that have the STA1 gene (or related). There are definitely others that have it too, not just Belgians.

Having that gene doesn't inherently mean it'll super-attenuate. That's what White Labs claims. They are upfront about it being present but claim it won't misbehave. Presumably other companies are following suit. Trust that or don't.

I don't know if Mangrove Jack has done any genetic analysis of their yeast (PCR I think it is? Not my area of expertise), but it may be worth asking the question a different way ("does the strain in question have the STA1 gene" rather than "does it have diastaticus").
 
I was interested in some of the Mangrove Jack's Belgian yeasts, but I couldn't find any info about it on the their website, so I emailed and asked. The answer was “To the best of our knowledge and testing, none of our yeast contain diastaticus”. Certainly the Mangrove Jack's company is the ultimate authority on their yeast, but I thought it was commonly agreed that many Belgian yeasts contain diastaticus. Any thoughts?

You spoke to a salesman rather than a techy, and they just palmed you off with something that feels warm and fuzzy but is BS.

Whilst it's a lot more complicated than "many Belgians contain diastaticus", you do have to watch the saisons in particular - and M29 is definitely diastaticus. You can sort of guess from the way the MJ describe it as "highly attenuative", but...it is.

I'm surprised they're not more paranoid about it, but then I guess that comes from being less exposed to the US legal system, and being more homebrew-oriented. It's true that there seems to be a lot of broken STA1 genes around, so strains will show up as positive on the DNA analysis but not make functional enzyme. I wouldn't sweat the bottle bomb thing too much - it's fine as long as you're expecting a beer to go down to say 1.003. The problem is when you have a yeast that you expect to go to 1.012 so you bottle at 1.012, but it's contaminated with something that will keep producing CO2 down to 1.003. Homebrewers can leave things in the FV for a little longer, a commercial brewery may send it to packaging shortly after seeing it hit 1.012.

And that high attenuation is part of saison character, otherwise you've got something more British.
 
It truly depends whom you talk to or which questions you ask - as Milk The Funk posts exactly the opposite answer regarding M29 - "Confirmed to be Saccharomyces cerevisiae var. diastaticus. Robbert Roost private email correspondance with Mangrove Jack customer service; forwarded to Dan Pixley. 12/14/2017"

In addition, there's a great resource provided by fellows from Sweden's Craft Labs - https://craftlabs.se/diastaticus-days/, where you can download a table with known diastaticus yeast. In there they listed both M29 and M31.
 
If the average attenuation is greater than like 86%, it's probably diastaticus.

The Mangrove Jack's website doesn't show an attenuation percent, but they give a description. M29 (French Saison) is "very high" - M47 (Belgian Abbey) is "high". Probably, the "very high" yeasts can be assumed to contain diastaticus, and the "high" yeasts do not. I'm a little paranoid about bottle bombs (including possible problems with subsequent batches using "normal" yeast), so I'm not sure about trying this just yet.

I contacted again and asked about the presence of the STA1 gene but haven't got a response yet. Between the weekend and Christmas, it might be late next week before I get a response. And given some of the information posted in this thread, I don't know how much confidence to have in any response.
 
I'm a little paranoid about bottle bombs
Bottle bombs are super easy to prevent with standard precautions.

1. Clean and sanitize your cold side equipment and bottles to prevent contamination from batch to batch.
2. Make sure beer reaches stable s.g. before bottling (unless you're doing something fancy).
3. Calculate priming sugar, dissolve, and mix properly if batch priming.

Lots of people make saisons, other Belgians, and even Brett beers without using separate equipment.
 
If the beer reaches terminal gravity before bottling, I see no problem with using any yeast whether it be STAx or not. When you bottle condition, calculate for the expected attenuation. I use diastaticus positive yeasts all the time and have never had an issue. I do however practice OCD level hygiene as to not cross contaminate other brews. I think the all the fear about it is over-rated.
 
I used Belle Saison yeast once. It chewed through most of the sugars quickly in the first week like normal. Fortunately I paid close attention to the slow fizz that continued to occur for 3 more weeks after that (glass fermenter). It finished at 1.002. If I had bottled right away after I wished the fermentation was complete instead of after a full month when it truly was complete, I would have had bombs. But since I paid attention, it wasn't a problem at all. Even won a silver medal.
 
The only STAx (good way of phrasing that by the way) positive yeast I've had a bad experience with is WLP099.

I don't know if it's confirmed diastaticus or not (it's listed by WLP as having STA1), but it chewed what should have been an 11% Barleywine to a near 14% one and took it to 0.7P IIRC. Certainly behaved like diastaticus.

Never had a cross contamination issue, and used French Saison a lot at home (Belle too once).

However, since all this diastaticus stuff has come out (and especially reports that Belle and possibly others can form a biofilm), separate plastic or heat pasteurization (basically treat it like Brett) is a worthwhile precaution in my book.
 
The only STAx (good way of phrasing that by the way) positive yeast I've had a bad experience with is WLP099.

I don't know if it's confirmed diastaticus or not (it's listed by WLP as having STA1), but it chewed what should have been an 11% Barleywine to a near 14% one and took it to 0.7P IIRC. Certainly behaved like diastaticus.

WLP099's an interesting one, it seems to be a mix of a diastaticus beer yeast (which smashes up the complex sugars) and a wine-like yeast that has the ABV tolerance to ferment it all out.
 
WLP099's an interesting one, it seems to be a mix of a diastaticus beer yeast (which smashes up the complex sugars) and a wine-like yeast that has the ABV tolerance to ferment it all out.
I was not pleased. Never using that strain (or if what you're saying is accurate, a blend?) again. If I remember this was before they had started disclosing this kinda stuff. It was a good few years ago. I was trying to figure out how it happened at the time, and once I learned it showed diastaticus genetics, and that I was nowhere near its tolerance, no wonder it chewed so far down.
 
WLP099 took a 1.135 OG beer down to 1.020 for me. I was pretty surprised.
 
3711 is a known STAx evil earth destroying monster (as is 565). Commercial and home brewers have been using it for many years without issue, but they are aware of, and adjust their processes for, the outrageous attenuation capability. That yeast can ferment distilled water and old gym socks. And for the record, it's a fantastic strain that still produces great beer. Mix 3711 with some harvested and cultured Dupont dregs (another accused planet killing yeast) and you have a great saison blend.
 
So I wrote back and asked about the STA1 gene. Someone else answered:
"Some of our strains do contain Saccharomyces cerevisiae var. diastaticus.

M47 Belgian Abbey does not, but other Belgian type strains such as M31 Belgian Triple and M41 Belgian Ale do, along with M29 French Saison.

Just to confirm that M21 Belgian Wit also does not, and nor do any of the other (non-Belgian) strains.

Hope this helps."

I feel a lot better about this answer.
 
The only STAx (good way of phrasing that by the way) positive yeast I've had a bad experience with is WLP099.

I don't know if it's confirmed diastaticus or not (it's listed by WLP as having STA1), but it chewed what should have been an 11% Barleywine to a near 14% one and took it to 0.7P IIRC. Certainly behaved like diastaticus.

Never had a cross contamination issue, and used French Saison a lot at home (Belle too once).

However, since all this diastaticus stuff has come out (and especially reports that Belle and possibly others can form a biofilm), separate plastic or heat pasteurization (basically treat it like Brett) is a worthwhile precaution in my book.

That’s really interesting regarding WLP099, I used it in a 120 min clone (added after 1318 stopped). Repeated dosing with sugar and the beer never went past 1.019, kegged and then bottled with no additional bottle fermentation.

This was just this past year, so maybe they’ve changed this offering?
 
WLP099 is a bit of a funny one, as it appears to be a (presumably alcohol sensitive) diastaticus mixed with a wine-like yeast that has high ABV tolerance so can keep chomping the simple sugars released by the diastaticus. So could it be that you'd already reached a high enough ABV to kill the diastaticus, or it was suboptimal in some other way like nutrients etc?
 
WLP099 is a bit of a funny one, as it appears to be a (presumably alcohol sensitive) diastaticus mixed with a wine-like yeast that has high ABV tolerance so can keep chomping the simple sugars released by the diastaticus. So could it be that you'd already reached a high enough ABV to kill the diastaticus, or it was suboptimal in some other way like nutrients etc?

Seems plausible, since the WLP099 starter was added to 9-10% abv beer already. I do think it’s possible WL cleaned up the yeast offering too, removing the STA1 yeast strain.
 
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