Rotten Egg Smell - fresh grapes

[szymek]

Hi Folks,

i'm relatively new to home wine making - this is my 3rd year doing it. Past 2 years i've had great success and wine turned out quite well. I've made wine from local grapes in Ontario (NY Muscat, Concord, Niagara white) and California (Merlot). Always wine turned out fantastic.

This year i decided to spend more money and i got premium local grapes that are typically harvested Mid October. I picked up Riesling and Cabernet Franc.

Essentially I crushed and pressed Riesling on Oct 21 when i got it. Suger content was 20.5 BRIX so i added approx 1.2 kg of sugar for 54L demijohn. Must tasted good and i had no concerns.

I did not sterilize Must - i've been following steps from old school wine maker that has been making wine (for personal drinking) for about 20 years. I just let the natural occurring yeast do the job - which i had success last 2 years.

On Sunday (Oct 22). I go down to basement and i find entire basement smells of rotten eggs. At first i thought my dog had accident and after looking through entire basement, it turned out it's coming from my Riesling!!! I understand this Hydrogen Sulfide. Based on what I've read it usually happens toward end of fermentation if anything. In my case it's at the very beginning. Maybe it's something they sprayed in October to keep mold out?

Cabarnet franc i crushed and it's sitting on skins in barrel - i plan on pressing Cab after 7 days. Yesterday Cabarnet looked and smelled good. This am when i went to punch the cap, i started to get little smell of rotten eggs - nothing close to Riesling though. But still - i'm frustrated and concerned that i will loose those 2 batches and that's my wine for next year. :-(

What should i do now? should i add Campden Tablet or Potassium metabisulfite to sterilize now - given i just pressed the juice 2 days ago (riesling)? and then add wine yeast? or just wait it out?? Is there anything is should do with Cab given it's just sitting on skins now - should i sterilize and restart yeast culture with wine yeast?

 

[jpsmithny]

Take a hydrometer reading so you know how fermentation is progressing.

The yeast needs oxygen in the initial phase of fermentation.

On the Reisling, rack it between two sanitized buckets so it gets plenty of violent splashing. Continue to do so until you can no longer detect the H2S. Then you can airlock. Add KMeta if it is finished fermenting.
On the Cab, when you punch down the cap, stir that mother like crazy to get as much oxygen to the yeast as possible.

Did you use yeast nutrient at all?

That can help when added at the correct dosage and time.
Let us know how it goes and good luck

 

[szymek]

Kmeta and campden are the same right?

In terms of riesling
I'll measure sugar content as soon as I get home. But it's been only 2 days since I pressed so I'm assuming fermentation is beginning. White grapes I always crushed, pressed and placed in demijoh on same day.

Should I add campden now, and pitch yeast tomorrow? I guess that would kill off naturally occurring yeast.

In terms of Cab, would it make sense and campden and add wine yeast to restart fermentation?

Stirring makes sense. As this am, before I punched the cap smell was nice. Very fruity. But after I stirred it I got rotten egg smell.

 

[jpsmithny]

Kmeta and campden are the same right?

In terms of riesling
I'll measure sugar content as soon as I get home. But it's been only 2 days since I pressed so I'm assuming fermentation is beginning. White grapes I always crushed, pressed and placed in demijoh on same day.

Should I add campden now, and pitch yeast tomorrow? I guess that would kill off naturally occurring yeast.

In terms of Cab, would it make sense and campden and add wine yeast to restart fermentation?

Stirring makes sense. As this am, before I punched the cap smell was nice. Very fruity. But after I stirred it I got rotten egg smell.

Yes, Campden and Kmeta are both Potassium Metabisulphite.

Check how far along fermentation is before adding any campden.
If it's progressing let it alone but add nutrient if possible.

Your yeast is stressed for whatever reason. That's why you are getting H2S.
You need to give it some oxygen and nutrients.

I had the same scenario you did and honestly, splash racking and stirring are what saved those batches.

Now I pay close attention to the beginning phases of fermentation and only pitch rehydrated yeast using goferm.
I also use Fermaid K or O as additions.

 

[pete1325]

My Cab from grapes sat for three weeks after pressing. I just racked this weekend....it also had an "off smell" to it......typically not the norm for me. I gave it a vigorous racking, this morn it smelled normal.

 

[szymek]

Ok. I didn't add any nutrients. I never did. But something is going wrong this time. I have some nutrients at home but I believe they expired beginning of this year. But as far as I know as long as they are stored in cool and dry place they don't expire. I was told it's just gov't law to put expiry date - can it be true?

I've heard of this happening towards end of fermentation. But never on 2nd day.

I was thinking of racking Riesling, but I was concerned about stalling fermentation. But I will follow your suggestion and I will rack it tonight. I really want to save it.

 

[jpsmithny]

Ok. I didn't add any nutrients. I never did. But something is going wrong this time. I have some nutrients at home but I believe they expired beginning of this year. But as far as I know as long as they are stored in cool and dry place they don't expire. I was told it's just gov't law to put expiry date - can it be true?

I've heard of this happening towards end of fermentation. But never on 2nd day.

I was thinking of racking Riesling, but I was concerned about stalling fermentation. But I will follow your suggestion and I will rack it tonight. I really want to save it.

Rack it vigorously as many times as needed until you can't smell the H2S anymore. You are not going to hurt it.
I literally poured it between two buckets maybe 10 times and then put it back in carboy. Wine turned out very well.

 

[szymek]

Alright. I'll provide update later tonight when I rack it.

Do you think this was caused due to native yeast?

One of the main reason I got into home wine making is that I want to stay away from any chemicals being added to my wine. I only added sugar after crushing to bring to 23brix. Although I'm novice, I was able to create very tasty wine. And I find it that I never have headache after drinking my own wine.

Having said that. I'm open to trying different things and evolve my process as I learn every year from my mistakes. What are your thoughts about adding SO2 after crashing grapes to kill off any bacteria and native yeast? Then pitch wine yeast to start fermentation from clean slate with specifically chosen yeast strain?

 

[szymek]

Once i rack I will add nutrients and i'm thinking of adding pack of wine yeast - is that good/bad idea?

 

[sour_grapes]

For God's sake, add nutrients! That is more than likely the problem.

I am no expert, but I wouldn't try to kill the native yeast at this point. However, I would add a starter of EC-1118, and see if it can take over the job.

But most of all, add nutrients!

 

[szymek]

ok - doing it now.

what about Cab that is sitting on skins - when i punch the cap i'm starting to get that smell of hydrogen sulfide. should i add nutrients and yeast? or wait till i press in few days? i'm assuming i should add now - but just triple checking.

 

[szymek]

update:

Riesling:
Suger content today 21 brix - i had it at about 23 brix on Oct 21. I've racked it and splashed it between 2 buckets 10+ times. I found that juice did not really smell that much - just the gasses coming through air lock. but i splashed it until the distinct H2S smell went away and i could start pick up sort of fruity smell. It took my a while as this batch is 54L. Very stinky business - smell got into main room from basement (not happy family - but had to be done). I tasted the must keeping in mind i might need to spit it out - but to my surprise must tastes quite well and nothing unusual. Then I added one pack of EC-1118 and dose of nutrients.

Cabernet Franc:
Suger content same as Riesling - i had it at 23 brix and today measures at 21 brix. However, when i punched the cap this evening, i am definitelly getting the H2S smell :-(. i've punched the cap and stirred it couple times this evening and I've added one pack of EC-1118 and dose on nutrients and gave it final stir for the night. This is about 54L batch as well.

Now my fingers are crossed that i can bounce back from this - i'm following advice here and did not sanitize to restart the fermentation cycle, but i racked / splashed it and added yeast/nutrients. It would be a shame to loose both of those batches.

 

[JohnT]

I hate to say it, but the only thing good about the good old days is that they are behind us. At times tradition can get in the way of making good wine. Today, we have the benefit of past knowledge and centuries of innovation, so why make use of it?

I am not a fan of natural fermentation. You honestly have no idea what strain of yeast you will be dealing with. IMHO is comes down to the luck of the draw. This time, I am afraid that you have picked up a natural yeast that is very vulnerable to H2S and yeast break down. As others have said, adding yeast nutrient might have prevented this problem.

Why go natural when winemakers have been cultivating yeast strains for centuries? There are strains that have been bred to be better suited for fermenting wine.

One recommendation I could make is to make sure to splash-rack off the gross lees as soon as is prudent.

 

[Smok1]

You said you added one pack of ec-1118? Was it the 5 gram packs? Because those are good for 5-23 liters, given your doing 54 liter batches id probly rehydrate 3 packs per batch just to make sure you dont stall out before fermentation is done. Ec-1118 can handle a little bit of so2, its a good idea to sanitize stuff, i have a spray bottle i blast everything that touches my wine.

 

[NorCal]

You should be ready to rock and roll now. Don’t let a little h2s spoil your day, I’ve had wines that had ferments that struggled and turned out fine. Stay with it.

The best solution to H2S is prevention, sanitize, good fruit, kill off native yeast and bacteria, nutrient, selective yeast, control ferm temp, press when dry.

 

[balatonwine]

Riesling on Oct 21 when i got it. Suger content was 20.5 BRIX so i added approx 1.2 kg of sugar for 54L demijohn.

For what it is worth, Riesling is a often low alcohol wine. Brix of 20.5 if not abnormal. No need to add sugar as long as ph and TA are otherwise in balance with that brix.

I did not sterilize Must - i've been following steps from old school wine maker that has been making wine (for personal drinking) for about 20 years. I just let the natural occurring yeast do the job - which i had success last 2 years.

A few comments about "natural fermentation".

First off, a better term for this is either "spontaneous fermentation" or "unaided fermentation". Because "natural" can be misleading.

While so called "natural fermentation" is quite in vogue, it really can not be done haphazardly with consistent results. The reason being is that the yeasts that are part of such fermentation are unknown, especially for hobbyists. Yes, there are many large wineries in Europe that do such "natural" fermentation routinely, but they can because of history. That is, the yeasts that start their fermentation are not really originally sourced form the grapes, they are rather from the winery. That is, for decades and centuries of making wine, certain yeast strains that created successful wine became naturally selected for in the wineries. These yeast cells are everywhere in the winery. On all surfaces (despite cleaning) and in the air. And they will inoculate the must and finish fermentation despite what "unknown" yeasts that were on the grapes stared the fermentation. These ubiquitous yeast strains are basically feral and selected strains from basic selective biology happening in the winery (just because the selection was not done in a test tube but in a barrel does not make them any less the product of selection). Most hobby wine makers do not have such a build up of successful strain where they make their wine. They then have to hope what is on the grapes will be a good yeast. That is if-y at best. It may work. Or it may not.

Of course, your chances of getting a good yeast on a red grape variety is higher than on a white. Why? Because many vineyards dump their post pressing material back into the vineyard, and the red wine press cakes have a plethora of great yeast because those pressing have experienced fermentation time, while white wine cake pressings have not. The red wine press waste then start to inoculate the vineyard with desirable feral yeast (which are not otherwise natural in such concentrations to that site -- which is why I say successful spontaneous fermentation is not really "natural", it is a product of human action and manipulation even if such is unplanned). Thus your chances of getting good yeast to have a successful spontaneous fermentation is better for red wines than for white. Unless you have a decades old cellar with a lot of feral yeast floating around, to get consistent results, I do recommend you inoculate all white wine must with a commercial yeast.

Maybe it's something they sprayed in October to keep mold out?

This is possible. If a late season spray with any residual sulfur was left on the vines, then that sulfur can contribute to H2S problems. Which is why if you are not growing your own grapes, it is good practice to add K-Meta, nutrients, and add commercial yeast (especially one that does not produce H2S) to help prevent problems. Because you really have no idea what environment those grapes were really exposed to before you acquired them.

 

[szymek]

Thank you for all the feedback - this is great.

The person I learned about wine making he never sanitized must nor added any wine yeast. I was successful last 2 years, but this year was definitely a lesson learned.

I haven't really done much research online and I'm glad i found this forum. Although i wanted to stay all natural, but based on my experience this year i will start off with fresh yeast most likely so I don't take any chances.

Bit of an update - White wine is already bubbling again probably bubble every 5 secs. so is looking good and....... i don't have the rotten smell anymore (well mostly). Seems that splash racking, adding nutrients and wine yeast did the trick!! I only added one pack of EC-1118 which is meant for 23L. My batch is 54L. Although bubbling has started - should i still add another pouch to ensure there are sufficient yeast? or given that fermentation started and i don't really have the smell anymore, i should just leave it?

In terms of Cabernet which is sitting in barrel on skins - it still has bit of smell, probably bit less than yesterday. I will add another pouch of EC-1118 this evening.

(i had to pick up more yeast today, as i only had 2 pouches on hand).

 

[FXibley]

Yeah I'm pretty sure the reason our "natural" fermentations are so consistent is due to the fact we have been making wine in the same cellar for 25+ years. We crush our concord grapes up at the vinyard and crush our grapes from Cali in the cellar, where the press is located as well.

 

[JohnT]

Although i wanted to stay all natural, but based on my experience this year i will start off with fresh yeast most likely so I don't take any chances.

I applaud your efforts to stay all-natural, but what is all-natural anyway?

 

[szymek]

Hi John. I tried not to use sulphite or any stabilizers and let wild yeast do the job.

As an example my sister is allergic to wine. Within one glass her lips swell up. But she can drink my wine without any issue. Looks like she is allergic to sulphite or whatever else is added to must during production process.

I used less noble grapes in the past (if that is correct term). But having said that, I'm just learning and this is my only 3rd year.

White continues to smell great now. And reds that are sitting on skins are still bit stinky but getting better. Looks like things are turning around after aerating, adding wine yeast and nutrients. Looks like wine yeast are taking over.

This was great lesson learned. My process will evolve and change. I think I took way too much risk.