milehiscott
Junior
Is this mold? I am 1 week into the primary on a Merlot kit. I have never had this happen. Did I kill it? Is there a way to save it? The little dark things are oak chips.
Help! Did I Kill It?
- Thread starter milehiscott
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Is this mold? I am 1 week into the primary on a Merlot kit. I have never had this happen. Did I kill it? Is there a way to save it? The little dark things are oak chips.
That is definitely mold. We’re you stirring the wine often? What is your SG?
I haven’t had this issue so I hope others can weigh in on a possible fix (if possible). In the meantime, carefully scoop off the mold, strain out the chips and get it in a carboy… filled up and airlocked. Give it a dose of K-meta too.
Definitely mold. I've never had to deal with it before, so I'm guessing -- go with @ChuckD's idea of skimming the mold off, and hit it with a double-dose of K-meta. I wouldn't put it under airlock yet, as it needs stirring -- I'd do it 2 to 3 times per day.
Did you stir your must daily? If not, your batch is the poster child for "why the must should be stirred daily".
Did you stir your must daily? If not, your batch is the poster child for "why the must should be stirred daily".
Looks like mold to me too.
More things to consider -
Yeast is a single cell, molds can be more complex and filamentous.
Some mold produces mycotoxins. The "toxin" part of mycotoxin is a darn good clue that it's not good.
https://moldhelpforyou.com/mycotoxins/
I have no experience with mold on must but I would choose caution. And by caution I mean curse like crazy, dump it, start a new batch.
More things to consider -
Yeast is a single cell, molds can be more complex and filamentous.
Some mold produces mycotoxins. The "toxin" part of mycotoxin is a darn good clue that it's not good.
https://moldhelpforyou.com/mycotoxins/
I have no experience with mold on must but I would choose caution. And by caution I mean curse like crazy, dump it, start a new batch.
Molds require air to grow. Your first line of defense is to have active fermentation which is producing CO2. As the sugar goes down/ production of gas slows, mold can be stopped by putting it in a carboy with air lock. If you have beer equipment you might keep it in plastic longer cover the bucket and flood the surface with CO2.
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milehiscott
Junior
I have never used Potassium Metabisulfite. I assume it will kill my yeast and I will need to restart the yeast?
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Probably won't kill your yeast. Assuming it is commercial yeast and not nearly done fermenting. Commercial yeast tends to laugh at K-Meta (Potassium Metabisulphite), unless it is stressed out.
In addition to what Craig said, K-meta is a general preservative and antioxidant. Wine can have a significantly longer shelf life if K-meta is used properly (e.g., 1/4 tsp per 19 to 23 liters).
milehiscott
Junior
This is my primary. The commercial yeast is just getting started.
IME, most commercial yeast will survive a triple dose (3/4 tsp in 19-23 liters), so it's not a problem. A triple dose is far from ideal, but it works.
No, it won't directly kill the yeast.
I restarted a stuck ferment by adding kmeta. Yes, unexpected and certainly not my plan. Was going like gangbusters the next morning. Live and learn.
milehiscott
Junior
Thanks for your help everyone!
I used a strainer with a coffee filter to clean out the mold. I then used some K-meta. I also changed the plastic cover for the primary, in case there were spores. The next day everything seemed better, but still no fermentation type smells or action. I added a new packet of the same yeast. After that, everything smells, looks, and acts like normal.
When I started (4/7) the Specific Gravity was 1.078
The day I added the new yeast (4/13) it was the same.
On 4/24 the S.G. was1.042
Now (4/27) it is 1.012
It looks like the wine is back on track.
Thanks!
I used a strainer with a coffee filter to clean out the mold. I then used some K-meta. I also changed the plastic cover for the primary, in case there were spores. The next day everything seemed better, but still no fermentation type smells or action. I added a new packet of the same yeast. After that, everything smells, looks, and acts like normal.
When I started (4/7) the Specific Gravity was 1.078
The day I added the new yeast (4/13) it was the same.
On 4/24 the S.G. was1.042
Now (4/27) it is 1.012
It looks like the wine is back on track.
Thanks!
If you still have it in a bucket, now would be the time to transfer to a carboy. Yeast are done reproducing so they no longer need oxygen. Top up the carboy and add an airlock. If your pH is below 3.4, and with the alcohol content you should be Ok.
