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derekjames100

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Pitched BM4x4 on Thursday. Cap formed Friday added 1g/gallon fermaid k due to company recommendations. This morning, H2S smell, temp 92 and Brix down from 23 to 8

What did I do wrong and how do I fix this? I added another 1g/gallon fermaid k and might get some ice bags.

As much info as you can provide the better!

Thanks!
 
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If from grapes, usually half dose at the start of fermentation (once a cap forms) and half at approx 1/3 of sugar depletion.
 
Ummmm, ditto. You need to tell us a lot more than you have. We don't even know if this is grapes or another fruit!!


This is the "winemaking from grapes" section.

72% Sangiovese 28% Barbera.

I added the second serving of fermaid k and have been punching down all morning. Not smelling as much H2s now as a yeasty sharp smell of aggressive fermentation. I took room temp down to 50 and put a few bags of ice around the fermenters to try to get it from 92 to 75 degrees. Brix went from 23 to 8 in 24 hours.
 
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Pitched BM4x4 on Thursday. Cap formed Friday added 1g/gallon fermaid k due to company recommendations. This morning, H2S smell, temp 92 and Brix down from 23 to 8

What did I do wrong and how do I fix this? I added another 1g/gallon fermaid k and might get some ice bags.

As much info as you can provide the better!

Thanks!

92*F is way out of spec for this yeast. Max listed on Lallemand's site is 28*C which converts to 82.4*F. Your yeast is probably a little stressed out, but obviously doing a good job munching on the available sugars. I'd also use Fermaid O vs. K as you won't see such a sharp rise in must temperature from using it, especially if you are going to exceed the limits on the tech sheet for the yeast, IMHO.
 
I was only going to add 0.5g/gallon of fermaid k for the first dose as I was told but the person at lallemand said to use 1 g/gallon now and another at 1/3 drop. She said no downside to adding too much at start. I thought it would minimize the chance of stress, but do you think it made the yeast "too happy"????
 
Sure seems like it did! In comparison I only added half at cap formation (Fermaid-K) on my BM4x4 and the other half 2 days later and my must temp only got up to around 82.
 
I was only going to add 0.5g/gallon of fermaid k for the first dose as I was told but the person at lallemand said to use 1 g/gallon now and another at 1/3 drop. She said no downside to adding too much at start. I thought it would minimize the chance of stress, but do you think it made the yeast "too happy"????

It may have and I think you will be fine. As was pointed out above the very active fermentation (an exothermic process) likely contributed to the unusual rise in temperature which stressed the yeast and lead to the H2S odor. Cooling it into the high 70's, if possible, should help. Good luck. Sounds like a very interesting blend you have there.
 
Lol!! I'm hopeful I'll at least get some good color from this! I may add a little reduless after I press then rack off gross less a few days later. Sound like w good plan to be safe? Any downside?
 
Lol!! I'm hopeful I'll at least get some good color from this! I may add a little reduless after I press then rack off gross less a few days later. Sound like w good plan to be safe? Any downside?

I would think you'd want to wait until after you press and even after you do an MLF (if you are going to, might want to consider if acids are high) and taste it before considering using reduless.

Looks from your other post like you used Lallzyme EX, so I imagine your skins will look like little gray toupees by the time you press. The Opti-red should help preserve the color for quite some time if you can believe the literature on it. Don't have a wine old enough to say from first hand experience.

At least an extremely active ferment is better than a stuck one!
 
Thanks all!

Is it not true that h2s usually forms during a stuck fermentation with longer lag phases when yeast are dying off and stressed?

My yeast are rocking and roll and couldn't be happier? So what w h2s?

Seems the h2s is mild. I'm not smelling much fruit now but seems like a very yeasty sharp smell? Burns my nose if I get close...sound familiar to anyone?
 
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Just annoying this all happened in 12 hours. Cap formed last night, I added nutrients at 8pm. This morning I checked it the Brix basically dropped from 23 to 8 overnight. I never could have predicted that. Hopefully the yeast can use some of the extra nitrogen I have them tiday even though alcohol content probably above 10.
 
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What fun would it be if it was predictable? We enter this hobby lacking some information that can only be obtained by experience. Next time it goes like this you'll know what to expect and how to react. Looks like your experience will end up with a finished product that you can enjoy, I don't think we can hope for much more!
 
This is my 4th year I will be using some BM4X4 yeast.... My crush is set for next Saturday. Read up on this months Wine Makers Magazine if you can get a copy in your hands.... It also dwells on the point of fermentation temperature is JUST as important as everything else you do during that process! Improper control of temperature and it is like neglecting nutrients all together.... It is a total process not just a chapter! Yes.... Your temp was way too high.....
 
This is my 4th year I will be using some BM4X4 yeast.... My crush is set for next Saturday. Read up on this months Wine Makers Magazine if you can get a copy in your hands.... It also dwells on the point of fermentation temperature is JUST as important as everything else you do during that process! Improper control of temperature and it is like neglecting nutrients all together.... It is a total process not just a chapter! Yes.... Your temp was way too high.....


What would you have done to properly control the temp? I pitched the nutrient and went to bed. When I woke up it was 92. Never would have predicted it.
 
I have never seen a must go from yeast pitch to blazing inferno overnight.

What was your must temp when the yeast was pitched?

Was there ANY yeast activity already going on when you pitched the yeast?

How much must do you have and how much yeast did you add to the must?
 
I have never seen a must go from yeast pitch to blazing inferno overnight.

What was your must temp when the yeast was pitched?

Was there ANY yeast activity already going on when you pitched the yeast?

How much must do you have and how much yeast did you add to the must?


I pitched the yeast Thursday. Friday evening the cap was forming, so I pitched the nutrient and went to bed. The inferno ensued overnight. I didn't check the temp when I pitched the nutrient but even if it was in the 70'-80s I'm not sure I would have changed anything. It probably would have made me more likely to feed them still but I'm not sure I would have iced it.
 
Usually you have a cap forming after 24 hours so that is completely normal so that leaves:

A) Too much yeast for Must volume causing a superfast buildup of fermentation
B) Too much Nutrients added somehow
C) Combination of both
 
Usually you have a cap forming after 24 hours so that is completely normal so that leaves:

A) Too much yeast for Must volume causing a superfast buildup of fermentation
B) Too much Nutrients added somehow
C) Combination of both



Thanks. I m sure it is answer C but I followed exactly what Scott labs suggested to me on the phone. I'm not sure I would have used less yeast to risk a stuck fermentation or less nutrient(as bm4x4 is a high nutrient requiring) in retrospect.

It's at 80 now and not foaming as much and smells much better so we will see how it goes.

Thanks so much
 
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