Unhealthy, sulfuric blueberry wine

[kungfuisdead]

Hey all,
I've been having trouble with some blueberry wine. It's my first wine from fruit I picked myself, so I'm desperate to help it along.
I've been following Jack Keller's recipe for highbush blueberry wine, and here's where I'm at so far.

• Washed, crushed, added 10lb blueberries (in nylon bag) to primary
• Added 8lb sugar, 3.75 tsp pectic enzyme, 7.5 tsp acid, 1.25 tsp yeast energizer, and campden

At this point, the recipe says to let it ferment until it hits 1.03, or about 5 days. However, it's been about 8 weeks, and my wine is still sitting around 1.05. I thought that maybe there were some solids preventing accurate hydrometer readings, so I racked it to secondary after about 5 weeks, straining through a nylon bag to remove solids. I still see consistent bubbling in my airlock, but the gravity isn't changing any faster than before.

Not only is the wine fermenting slowly, but it also has a harsh sulfuric smell. I've read that both of these symptoms can be caused by a lack of nutrients for the yeast or a low temperature. I have another wine in the same room going great and fermenting vigorously (1.085 -> 1.03 in 4 days), so I'm tempted to rule out temperature as the cause.

Should I be more worried for this wine? So far my strategy has been patience, but is there anything I can do to speed it up? I have plenty of DAP, which I've read could help.

Thank you!

 

[winemaker81]

Welcome to WMT!

This is a 1 US gallon batch? The recipe called for WAY too much sugar, more than the yeast can eat, so it's almost certainly fermented as far as it will. Yeast eats sugar until it runs out of sugar OR it produces enough alcohol to poison its own environment.

Is the smell sulfur or it is really nasty, like swamp gas or dog farts? I'm guessing the latter, which is hydrogen sulfide (H2S), which is produced when the yeast is stressed, typically by low nutrients.

Add a double dose of K-meta and stir the heck out of it. Do this in a ventilated area and run a fan, as the gas is noxious.

 

[kungfuisdead]

Welcome to WMT!

This is a 1 US gallon batch? The recipe called for WAY too much sugar, more than the yeast can eat, so it's almost certainly fermented as far as it will. Yeast eats sugar until it runs out of sugar OR it produces enough alcohol to poison its own environment.

Is the smell sulfur or it is really nasty, like swamp gas or dog farts? I'm guessing the latter, which is hydrogen sulfide (H2S), which is produced when the yeast is stressed, typically by low nutrients.

Add a double dose of K-meta and stir the heck out of it. Do this in a ventilated area and run a fan, as the gas is noxious.

Thank you! And no, this is a 5gal batch. And yeah, it's more dog fart than swamp gas, lol. What would the K-meta do?
Thanks so much for the help!

 

[winemaker81]

What was your original SG? Always include that in your posts, as it gives everyone else a better understanding of your situation. Generally speaking, the more information you provide, the faster you will get help.

You have a stuck fermentation, as 8 lbs sugar in 5 gallons is a low enough SG that the yeast probably didn't poison itself. Which yeast did you use?

K-meta binds with the H2S, rendering it harmless. A common question is "why am I adding sulfur to treat a sulfur problem?" The short answer is you are not -- you're adding sulfite to treat sulfide, completely different compounds that both contain sulfur.

Stirring will release the H2S, and it's gonna stink. I promise that you will regret it if you don't do it in a ventilated area and run a fan.

Add more nutrient -- at this point I'd go with whatever your package directions state. You may need to add another yeast starter, if the fermentation doesn't kick back in.

Full treatment for H2S may be more extensive. Let's get your ferment rocking again, then we'll discuss further treatment.

I encountered H2S last fall but caught it very early, so my treatment for it was easy. A detailed blog is here:

https://wine.bkfazekas.com/2022-grape-wines-in-detail/
Three years ago I had a worse encounter, which required more extensive treatment:

https://wine.bkfazekas.com/2020-red-blend-second-run/

 

[kungfuisdead]

What was your original SG? Always include that in your posts, as it gives everyone else a better understanding of your situation. Generally speaking, the more information you provide, the faster you will get help.

You have a stuck fermentation, as 8 lbs sugar in 5 gallons is a low enough SG that the yeast probably didn't poison itself. Which yeast did you use?

K-meta binds with the H2S, rendering it harmless. A common question is "why am I adding sulfur to treat a sulfur problem?" The short answer is you are not -- you're adding sulfite to treat sulfide, completely different compounds that both contain sulfur.

Stirring will release the H2S, and it's gonna stink. I promise that you will regret it if you don't do it in a ventilated area and run a fan.

Add more nutrient -- at this point I'd go with whatever your package directions state. You may need to add another yeast starter, if the fermentation doesn't kick back in.

Full treatment for H2S may be more extensive. Let's get your ferment rocking again, then we'll discuss further treatment.

I encountered H2S last fall but caught it very early, so my treatment for it was easy. A detailed blog is here:

https://wine.bkfazekas.com/2022-grape-wines-in-detail/
Three years ago I had a worse encounter, which required more extensive treatment:

https://wine.bkfazekas.com/2020-red-blend-second-run/

SG was 1.08, and I used lalvin rc-212. I'm gonna start by adding some more campden tablets and stirring. I'll be careful to vent the gas when I stir. Thanks so much for your advice!

 

[winemaker81]

SG was 1.08, and I used lalvin rc-212. I'm gonna start by adding some more campden tablets and stirring. I'll be careful to vent the gas when I stir. Thanks so much for your advice!

RC-212 is notorious for producing H2S. When using a yeast that has high nutrient requirements, it's best to use about 50% more than the nutrient directions state. Search for yeast strain charts -- there are a bunch available.

Campden are great for gallon batches, but for larger batches K-meta powder is cheaper and easier to use. Normal dosage is 1/4 tsp in 19-23 liters.

 

[Raptor99]

For future reference, 10 lbs. of blueberries in a 5-gallon batch is very low. For a good fruit flavor, you should use at least 5 lbs. of fruit per gallon.

 

[cmason1957]

I am going to guess that your Ph may be somewhat on the low side for a successful ferment, blueberries have a tendency to be somewhat acidic. You may want to test that and see where you are. Since it has fermented some, you will want to stir the sample you are going to measure the Ph in vigorously to remove any CO2 that might be in it.

 

[kungfuisdead]

For future reference, 10 lbs. of blueberries in a 5-gallon batch is very low. For a good fruit flavor, you should use at least 5 lbs. of fruit per gallon.

That’s what I’ve read is a common theme for Keller’s recipes, unfortunately. I have more blueberries in the freezer. Is there any reason not to add them now?

 

[kungfuisdead]

Thanks! I will be sure to check the Ph before addressing the potential nutrient issue

I am going to guess that your Ph may be somewhat on the low side for a successful ferment, blueberries have a tendency to be somewhat acidic. You may want to test that and see where you are. Since it has fermented some, you will want to stir the sample you are going to measure the Ph in vigorously to remove any CO2 that might be in it.

 

[winemaker81]

That’s what I’ve read is a common theme for Keller’s recipes, unfortunately. I have more blueberries in the freezer. Is there any reason not to add them now?

Treat the H2S first, then go ahead and add more fruit. You're still in active fermentation, so it's not a problem.

FYI -- typically 2.9 is the lowest pH that wine yeast thrive in. If it's 3.0 or above you're ok.

 

[Jovimaple]

@kungfuisdead And welcome to WMT!