Anyone had issues with mangrove jacks m20 yeast crapping out at 1.020?

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Monkhouse

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I did a brew on Monday just gone (Jon finch hefe weiss) and scaled back on the water a fair bit so got an OG of 1.064 (recipe states 1.050) so I was hopeful of a decent end strength and brewers friend estimated around 7.3%
However after an eventful start (see attached pictures) the yeast seems to have totally crapped out on me at 1.020. I can’t see any bubbles through the fv (clear fermentasaurus fv so can see everything)
I know it’s very early but like I said there’s naff all activity and I cannot see the hydrometer dropping down 11 points to the stated 1.009 which the recipe says.
I mashed at the stated 66c too bang on so was happy about getting the right sugars for fermentation.
Has anyone any issues using this yeast?
Btw I also pitched 2 packs of this yeast.
 

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Yes. I had exactly the same. It stopped at 1.020. it then massively overcarbed in the bottle. I don't know whether it woke up again, or it was a diastaticus infection I now know I had, or both.

It still tasted delicious though, both out of the fermenter and after it went to bubbletown in the bottle

I also had a batch of m21 (Belgian wit rather than Bavarian) cap out at 1.020. that one woke up after 2-3 weeks and fermented down to a respectable level.

My best advice would be to do a search for M20 and attenuation. See what comes up. Then I'd leave it for at least 3 weeks in the fermenter to see if it starts again.

I don't think I'll use either of these again. They are too finicky. I'll try fermentis or lallemand in the future
 
Right now I’m torn between the idea of getting a pack of Safale German wheat yeast or adding some table sugars or dextrose?
I’m so bloody annoyed this has happened m, I was wary about using mangrove jacks yeast again after I had a bad result last time and I wish I’d trusted my gut, mangrove jacks you absolutely suck at mAking yeast!!!
 
For German and American wheat beer I use CML Gretel which has an attenuation of 85-90%. I bought a M21 to make Hoegaarden but it’s attenuation is 70-75% so I’ll probably do a 50/50 M21/Gretel.
 
I did a brew on Monday just gone (Jon finch hefe weiss) and scaled back on the water a fair bit so got an OG of 1.064 (recipe states 1.050) so I was hopeful of a decent end strength and brewers friend estimated around 7.3%
However after an eventful start (see attached pictures) the yeast seems to have totally crapped out on me at 1.020. I can’t see any bubbles through the fv (clear fermentasaurus fv so can see everything)
I know it’s very early but like I said there’s naff all activity and I cannot see the hydrometer dropping down 11 points to the stated 1.009 which the recipe says.
I mashed at the stated 66c too bang on so was happy about getting the right sugars for fermentation.
Has anyone any issues using this yeast?
Btw I also pitched 2 packs of this yeast.
You won't hit the recipes target FG of 1.009 if you raised the OG by 14 points. Using the same yeast. 70-75% attenuation of 1.064 would be 1.019 down to 1.015.
 
You won't hit the recipes target FG of 1.009 if you raised the OG by 14 points. Using the same yeast. 70-75% attenuation of 1.064 would be 1.019 down to 1.015.

Yeah, I've made a couple of batches of (very simple) weiss using M20 and in both cases <checks notes> gravity went from 1044 to 1010, for a modest ABV of around 4.4%, which I prefer. But if you whack up the OG that much, you surely can't expect it to finish at the same point.
 
Early days and you're probably not as far away a first thought.

I've also noticed that the original recipe that quotes 1.009, uses WY3506 which is slightly more attenuating than M20.
 

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The problem is lowish attenuation 70-75% with M20 & M21. However that does not make them bad yeasts. I use M54 and M31 regularly and they are good yeasts with higher attenuation. However my go to yeasts are Crossmyloof which are consistently good. I wish however that CML had an equivalent of M54, M31, and M21.
 
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