Potassium Sorbate

[wineview]

@wineview By any chance did you top up with commercial wine after any of the past rackings? Residual sugar common in some commercial wines can cause slight co2 problems like this in bottled wine. I agree with the other comments above that residual co2 from inadequate degassing is probably the most likely cause, but just wanted to point out other possibilities.

On the subject of degassing. With the 2019 buckets I purchased, I noticed when I went to degass after fermentation was complete, the wine didn’t foam up and I thought that was odd. The wine was very heavy looking. I just racked another carboy into a bucket and started to whip it with my drill. Sure enough the wine foamed up. Funny that it didn’t six months ago. Anyway that may be the issue at hand. So now I have 25 gallons to rack and re-whip. At 25-30 minutes each, that’s pretty labor intensive. Oh well....here I go.

 

[wineview]

Yes I did top off with commercial wines

The commercial wine comment is a good observation. I checked the SG and it hasn’t changed unless the sugar from the commercial wine is hard to detect.

 

[stickman]

The small amount of commercial wine being used as top-up wouldn't add enough sugar to be easily detectable by a hydrometer, but it would be detectable by yeast.

 

[wineview]

The small amount of commercial wine being used as top-up wouldn't add enough sugar to be easily detectable by a hydrometer, but it would be detectable by yeast.

Copy that.

 

[jpwatkins9]

I just tried a bottle of 2017 cab bottled after a year in bulk aging In 2018. It had fermented down to 0.994. Did a bit of degassing with a paddle on a hand drill. It had been in the bottle for almost 2 years. No fizz. I suspect that any CO2 would have come out through the corks.

 

[Mario Dinis]

With a wine fermented down to 0.996 and no backsweetening, potassium sorbate isn't the fix for a slight fizz. I really doubt that it started alcoholic fermentation again. It is possible it started malolactic fermentation, but again, not likely. What is more likely is that it was bottled with some residual CO2 in suspension and that your wine required more degassing, either through waiting longer, vacuum racking to help remove it, or agitation to try to force it out.

I have the same issue and I really believe it needed more time degassing.

 

[Mario Dinis]

I should be more specific. Two weeks ago I bottled a cabernet from my September 2019 batch. I racked three or four times and made a couple of potassium metabisulphite additions over the months. I tried a bottle yesterday and there was a very slight fizz in the background. After looking at my notes I realized I did not add potassium sorbate. The wine fermented down to .996 so I’m not sure how this apparent re-fermentation started. What is the best way to handle this? Uncork, pour into a bucket and add re-hydrated potassium sorbate? Or can I add dry potassium sorbate to each bottle. Thanks.

It might have need a bit more degassing. I have the same issue.

 

[Johnd]

I suspect that any CO2 would have come out through the corks.

I have a 6 year old wine that was very lightly fizzy when bottled. Still is today. A good rule to practice is: “Don’t bottle fizzy or cloudy wine”.

 

[Scooter68]

"I suspect that any CO2 would have come out through the corks." (jpwatkins9)


Champagne is bottled with corks and it does not lose it's 'fizz'

 

[jpwatkins9]

True that Champagne uses corks, and I do make sparkling Rose’, but I use Belgian corks for bottling that are much denser than those that I use for wine. really put a bit of strain on my Portuguese wine press to get them in. I do drink those after about 6 to nine months also, where my wine can sit for a few years.

 

[bstnh1]

I have a 6 year old wine that was very lightly fizzy when bottled. Still is today. A good rule to practice is: “Don’t bottle fizzy or cloudy wine”.

I thought "don't bottle fizzy or cloudy wine' was one of the cardinal rules of wine making --- kinda like "garbage in, garbage out" in computer land. lol

 

[stickman]

The topic of co2 retention after bottling has been covered in the past. Looking at published data, the co2 loss over time in bottle is dependent on temperature and type of closure, but is in the range of around 200ppm lost over 5 years. The co2 content for finished wine really has to be detemined by taste, most of us don't do any measurements, but typical literature ranges are 200 to 500ppm for reds, and 500 to 1600ppm for white wine. Freshly fermented wine might be in the range of 1600 to 1800ppm co2, so using red wine as an example, if you degas and stop early at say 800ppm, it's going to take a long time of bottle aging to get down to the recommended level for a red wine.

 

[Johnd]

I thought "don't bottle fizzy or cloudy wine' was one of the cardinal rules of wine making --- kinda like "garbage in, garbage out" in computer land. lol

For me, it’s definitely a cardinal rule, though everyone doesn’t necessarily feel so strongly about it, just trying to allow for some flexibility I guess........LOL!!

 

[Rice_Guy]

@stickman do you have a CO2 reference, sounds like a good article/ a journal with useful info

 

[stickman]

There are several publications that have provided information throughout the years. I have Peynaud's book as well as subscription access to Practical Winery & Vineyard/Wines & Vines.

The saturation concentration of carbon dioxide at 50°F is about 2,000 mg/L (100 times that of nitrogen) or the equivalent of 3.6 g/L T.A. as tartaric acid. Recommendations for residual dissolved CO2 for wines range from 200 to 800 mg/L for reds and from 700 to 1,800 mg/L for whites to avoid “flabby” tasting wines. (Principles and Practices of Winemaking. R. B. Boulton et al, p. 434, Springer 1996)

The optimal co2 content is variable with the wine and is from 300 to 600ppm. Yet for other types of wine, carbon dioxide is undesirable, it brings out the acid taste, reduces the ambrosial flavors and accentuates the astringency and tannic hardness. (Peynaud, E., 1984, Knowing and making wine, Wiley-Interscience)


Older references are listed below as these articles include information about the effects of co2 in wine during storage and handling. I've attached the latest co2 data from Nomacorc as they did test some natural cork as a comparison; a good article, but not a journal.


Lewis, D.,1990, Blanketing in storage tanks. The Australian Grapegrower and Winemaker, April 1990
Allen, D.B, 1989, Inerting wine tanks, The Australian Grapegrower and Winemaker, pp 23 - 24, April
Afrox, 1993. Gas usage in wine making, Part one, Wynboer, pp 62-63, February
Westrick, M.,1996, Managing oxygen in white wine production. Practical Winery and Vineyard, pp 49 -52, May/June

 

[DizzyIzzy]

There are several publications that have provided information throughout the years. I have Peynaud's book as well as subscription access to Practical Winery & Vineyard/Wines & Vines.

The saturation concentration of carbon dioxide at 50°F is about 2,000 mg/L (100 times that of nitrogen) or the equivalent of 3.6 g/L T.A. as tartaric acid. Recommendations for residual dissolved CO2 for wines range from 200 to 800 mg/L for reds and from 700 to 1,800 mg/L for whites to avoid “flabby” tasting wines. (Principles and Practices of Winemaking. R. B. Boulton et al, p. 434, Springer 1996)

The optimal co2 content is variable with the wine and is from 300 to 600ppm. Yet for other types of wine, carbon dioxide is undesirable, it brings out the acid taste, reduces the ambrosial flavors and accentuates the astringency and tannic hardness. (Peynaud, E., 1984, Knowing and making wine, Wiley-Interscience)


Older references are listed below as these articles include information about the effects of co2 in wine during storage and handling. I've attached the latest co2 data from Nomacorc as they did test some natural cork as a comparison; a good article, but not a journal.


Lewis, D.,1990, Blanketing in storage tanks. The Australian Grapegrower and Winemaker, April 1990
Allen, D.B, 1989, Inerting wine tanks, The Australian Grapegrower and Winemaker, pp 23 - 24, April
Afrox, 1993. Gas usage in wine making, Part one, Wynboer, pp 62-63, February
Westrick, M.,1996, Managing oxygen in white wine production. Practical Winery and Vineyard, pp 49 -52, May/June

Feels like I'm back in college studying chemistry. LOL

 

[Rice_Guy]

A lot of wine is chemistry, ex the disassociation constant for meta yielding a pH dependent solution which further disassociates into SO2.

Feels like I'm back in college studying chemistry. LOL

 

[cmason1957]

A lot of wine is chemistry, ex the disassociation constant for meta yielding a pH dependent solution which further disassociates into SO2.

and you have to understand almost zero chemistry to make good wine. It helps, to know what is going on and to know what the tests are telling you, but for us at home not much is really needed.