WineXpert Musty wine aftertaste

[Hobbit]

I do not get the after taste on all batches.
My thoughts on possible causes-- bulk age for 6 months in carboy, too much oak, might be over sanitizing, not racking enough. Appreciate any thoughts.

Also, how long should a sealed pack of yeast last?

 

[ratflinger]

Sanitation - No, one can not over-sanitize. Now if you left sanitation chemicals behind, in larger amounts, that could be an issue.
Bulk Aging - Doubtful, unless you allowed too much oxygen infiltration. Commercial wineries bulk age for a year or more.
Too much oak - Could be, as too much tannin will definitely affect the taste profile.
Not racking enough - Sitting on the gross lees for an extended time can cause off flavors to develop.
Yeast - The package should have a date on it. If it was stored cold then I've seen articles stating up to 2 years. However, how that yeast acts in your bread, vs wine is a different story. If your yeast is approaching the Use By Date you should think about getting new yeast. Yeast is cheap, why risk your wine with questionable yeast?

 

[Hobbit]

Sanitation - No, one can not over-sanitize. Now if you left sanitation chemicals behind, in larger amounts, that could be an issue.
Bulk Aging - Doubtful, unless you allowed too much oxygen infiltration. Commercial wineries bulk age for a year or more.
Too much oak - Could be, as too much tannin will definitely affect the taste profile.
Not racking enough - Sitting on the gross lees for an extended time can cause off flavors to develop.
Yeast - The package should have a date on it. If it was stored cold then I've seen articles stating up to 2 years. However, how that yeast acts in your bread, vs wine is a different story. If your yeast is approaching the Use By Date you should think about getting new yeast. Yeast is cheap, why risk your wine with questionable yeast?

Another thought. I use natural corks but, not able to store them on their side. Could this cause the after taste?

 

[ratflinger]

Not unless you are storing them for so long that the corks dry out. How long have you stored them?

winemaker81 and others have had good luck with Numacor synthetic corks, apparently storing upright is no longer an issue.

 

[bluecrab]

Are you familiar with the smell of 'corked' wine?

"Corked wines smell and taste of damp, soggy, wet or rotten cardboard."
https://www.thekitchn.com/what-is-corked-wine-what-does-corked-wine-taste-like-164148
To me it smells of wet, musty newspaper. A few bottles of my wine had it. I believe it came from tainted corks.

 

[winemaker81]

Another thought. I use natural corks but, not able to store them on their side. Could this cause the after taste?

If you are using natural corks, the corks MUST be wet or you'll regret it. If you have cases stored upright, turn the bottles upside down. While it normally takes a fair amount of time for the corks dry out, nothing is certain.

As @ratflinger said, a fair number of folks use Nomacorcs, which can be stood up. However, decades of "store the wine on its side" has me storing them "normally".

 

[gsorrells]

Sanitation - No, one can not over-sanitize. Now if you left sanitation chemicals behind, in larger amounts, that could be an issue.
Bulk Aging - Doubtful, unless you allowed too much oxygen infiltration. Commercial wineries bulk age for a year or more.
Too much oak - Could be, as too much tannin will definitely affect the taste profile.
Not racking enough - Sitting on the gross lees for an extended time can cause off flavors to develop.
Yeast - The package should have a date on it. If it was stored cold then I've seen articles stating up to 2 years. However, how that yeast acts in your bread, vs wine is a different story. If your yeast is approaching the Use By Date you should think about getting new yeast. Yeast is cheap, why risk your wine with questionable yeast?

Sound advice. We own a small commercial winery. We store yeast in a fridge and discard it and buy new for the next vintage (1 year). Rinse with clean water several times after cleaning/sanitizing. Do you clean and sanitize your hoses and pumps? Lots of wineries find out that they don’t clean hoses very well.

 

[winemaker81]

We store yeast in a fridge and discard it and buy new for the next vintage (1 year).

I did the same, but now that I'm making overnight starters, I'm keeping yeast until it proves non-viable. At the cost of a bit of sugar and nutrient, the starter will demonstrate the yeast is still viable (or not).

 

[managuense]

What are your production and cellar conditions like? Is it moldy? That's the first thing that comes to mind when I hear someone say musty. You could very well be smelling mold.
Also- are you making this wine from a kit (juice) or from actual grapes? Moldy grapes result in moldy wines. Laccase would be the most common culprit and is caused by unchecked Botrytis in the field.

Maybe musty means something different to you than it does me. Any other descriptors if you disagree with the above?

 

[TurkeyHollow]

I'm still fairly new to this but for the past (10) years I've kept my cellar at around 62° F and 30% humidity. I feel the temp has worked out for me but I have a hard time with dampness (just don't like that musty smell in everything) so I run on the dryer side. I'm kind of hoping my cap seals are keeping my corks from drying out. Maybe someone can school me on lack of humidity...

 

[managuense]

I like to also run my barrel cellar at lower humidity levels (30-40%) to control mold growth. The only downside to this is that you will have more evaporative loss and will need to top your containers up more often.

For corked bottles, yes a higher RH is advised to prevent corks from drying out (60%). However I would ask how long you are planning to age your wines. If its less than 5 years I wouldn't worry too much about cork degradation. If you're planning to age longer than that you might want to address the humidity for corked wines.

 

[She’sgonnakillme]

I like to also run my barrel cellar at lower humidity levels (30-40%) to control mold growth. The only downside to this is that you will have more evaporative loss and will need to top your containers up more often.

For corked bottles, yes a higher RH is advised to prevent corks from drying out (60%). However I would ask how long you are planning to age your wines. If its less than 5 years I wouldn't worry too much about cork degradation. If you're planning to age longer than that you might want to address the humidity for corked wines.

Would using synthetic corks alleviate this concern?

 

[JohnW]

I'm leaning toward the corks being the culprit as well but here are some other thoughts:

My Italian brother-in-law makes wine from juice the way his ancestors did - without adding any yeast. Whatever wild yeast happens to be in the juice or floating around in his basement does the fermenting. It's fairly low in alcohol and a little sweet but often tastes quite good. Occasionally however it finds an unpleasant strain and smells rather like what you are describing. It seems unlikely that a wild strain would win out over the commercial stuff but I guess it's possible; especially if your yeast is old.

It is also possible that the good wine aromas are being lost during the fermentation process and all you have left are some unpleasant secondary aromas. One suggestion is to try to preserve the good aromas (must/juice, oak, etc.) by adding sacrificial tannins during fermentation. Also possibly slowing the fermentation by lowering the temperature may help.

 

[winemaker81]

Would using synthetic corks alleviate this concern?

Synthetic corks like Nomacorc do not dry out, but they do degrade with time, IIRC allowing more O2 to pass. The humidity in my cellar varies during the year, and mold on the outside of the cork was a problem before I switched to Nomacorc.

The Select 900 series, which typically do not have a descriptor other than the brand name, are rated for 5 years, meaning you can expect at least 5 years before they start seriously degrading. I expect to get about 7 years from them, as if the manufacturer is smart, their guarantee is a minimum value, so the corks should last longer. For my purposes they are sufficient.

If you honestly believe you'll age wines longer than 7 years, Nomacorc produces lines rated up to 25 years.

 

[TurkeyHollow]

I like to also run my barrel cellar at lower humidity levels (30-40%) to control mold growth. The only downside to this is that you will have more evaporative loss and will need to top your containers up more often.

For corked bottles, yes a higher RH is advised to prevent corks from drying out (60%). However I would ask how long you are planning to age your wines. If its less than 5 years I wouldn't worry too much about cork degradation. If you're planning to age longer than that you might want to address the humidity for corked wines.

I have some wines I plan to store longer than 5 years (plans don't always come to fruition though) and the ones I have already stored for about 8-9 years don't seem to have any degradation. Is it that they would come apart upon removal or would they start to leak? I also have an Aranizer used for air purification in the wine cellar. I was concerned that would shorten the life of the corks. I hope what I do for cellar hygiene aren't counterproductive to the quality of the wine I store... Any thoughts?

 

[winemaker81]

Is it that they would come apart upon removal or would they start to leak?

That is definitely a possibility, although there is also the problem of O2 ingress as the cork degrades.

IIRC, Chateau Laffite Rothschild sends a team around the world every so many years, and they will test CLR wines over a certain age. They use a very fine needle to withdraw a small sample and test it, and will recork bottles and provide a certificate of authenticity to go with the new cork.

If you are concerned, recork your old wines with a fresh cork. Do NOT wait until you find a problem -- at that point you're too late. It's like re-roofing your house -- if you wait until you have a leak, you've waited too long and have bigger problems. If you are a afraid of a problem, for the cost of a few corks, recork the bottles.

For most people, the problem is that most wines won't last 10 years, they'll reach the end of their life and start to decline. If your wines have reached age 8 or 9 and are doing good? That is seriously cool!

 

[TurkeyHollow]

That is definitely a possibility, although there is also the problem of O2 ingress as the cork degrades.

IIRC, Chateau Laffite Rothschild sends a team around the world every so many years, and they will test CLR wines over a certain age. They use a very fine needle to withdraw a small sample and test it, and will recork bottles and provide a certificate of authenticity to go with the new cork.

If you are concerned, recork your old wines with a fresh cork. Do NOT wait until you find a problem -- at that point you're too late. It's like re-roofing your house -- if you wait until you have a leak, you've waited too long and have bigger problems. If you are a afraid of a problem, for the cost of a few corks, recork the bottles.

For most people, the problem is that most wines won't last 10 years, they'll reach the end of their life and start to decline. If your wines have reached age 8 or 9 and are doing good? That is seriously cool!

That's very interesting. I really haven't given any thought to re-corking wines. I do use Lafitte Aglo 1+1 corks (with which I'm very happy). I guess I have some reading to do on the timing of it. I also use Argon (not at original bottling) so I may be able to use that to try to cut down some the O2 exposure during the process. I would love to figure a way to do it in a controlled atmosphere but that may be yet another rabbit hole to run down. Thanks for the food for more thought!

 

[managuense]

not to add to this project...but there are some high end producers who do this and when they re-cork the bottles they also bump the S02 a little to help keep the wine from falling apart. Food for thought I suppose but at some point it makes you ask the question, should these just be drank or put on life support indefinitely because I want to see them grow older....

There are tons of different enclosures out there with various life spans. I have always stuck to natural cork because at the end of the day that is what we are trying to do right? Preserve natural beauty. Nothing against synthetics just my own bias.

The short answer is yes synthetics will not dry out like a natural cork but will still degrade at some point. Life span varies depending on what synthetic you're using.

You might consider going with a natural cork over a 1+1 though. I use 1+1 on all whites that will be consumed in 1-2 years and natural cork for the wines that age longer.

 

[winemaker81]

when they re-cork the bottles they also bump the S02 a little

That's an excellent idea! To manage this, I'd dissolve 1/4 tsp K-meta in 50-60 ml distilled water (roughly 1/4 cup). Using a syringe, like used for acid titration, I'd add 2 ml to each bottle.

Overall, I'd say we have successfully dragged this thread onto a tangent. Long live the internet!!!

Getting back on track, @Hobbit, how long are you leaving wine on gross lees (thick sediment)? That can have an effect as well.

 

[Hobbit]

That's an excellent idea! To manage this, I'd dissolve 1/4 tsp K-meta in 50-60 ml distilled water (roughly 1/4 cup). Using a syringe, like used for acid titration, I'd add 2 ml to each bottle.

Overall, I'd say we have successfully dragged this thread onto a tangent. Long live the internet!!!

Getting back on track, @Hobbit, how long are you leaving wine on gross lees (thick sediment)? That can have an effect as well.

I rack 2x and then let it set in carboy for six months b4 bottling