CO2 level in wines

[SleepyDave]

I was looking for some way to measure the disolved CO2 in my wines today when I came across this:

“Wine emerges from fermentation with about two grams per liter of dissolved CO2, and it declines from there. At 500 milligrams per liter, the presence of CO2 is noticeable; at 1,000 mg/L, there is a slight perception of prickliness. The textbook recommendation is that age-worthy reds should be bottled with no more than 100-200 mg/L; light, fruity reds could benefit from about 500 mg/L, and whites, depending on stylistic intent, might range anywhere from 500 mg/L to 1,800 mg/L, from slightly punched up to noticeably spritzy.”

See https://www.winesandvines.com/templa...&content=86529

The page describes a couple of measuring techniques, costing from $13,000 to $250 but seems, in the end, to recomend the good old taste test. But I was most interested in the figures it gives for 'recomended' CO2 levels. It even goes on to discuss the methods used by some commercial wineries to increase the CO2 levels in their white wines.

Has anyone else seen these sort of recomendations before and does anybody try to apply them? I understood that removing every last trace of dissolved CO2 was an essential prerequisite to producing any decent wine.

[Cellar_Rat]

I understood that removing every last trace of dissolved CO2 was an essential prerequisite to producing any decent wine.

Nope.

Did some of this on a course. CO2 is part of the flavour profile. I use a taste test - its is quite obvious.
It is also helped by old ma' nature. if you ferment in September, the cold months post fermentation will hold the CO2 in. If you bottle during this time you need to address that. However if you bottle after your wine has been through another summer the warmer months warm the wine, which will naturally release the CO2.

... Alternatively, shake like a daemon.

[NorthernWiner]

Has anyone else seen these sort of recomendations before and does anybody try to apply them? I understood that removing every last trace of dissolved CO2 was an essential prerequisite to producing any decent wine.

I don't take any steps to forcibly remove CO2 from wine, or measure it, for that matter. I barrel age all my red wines and, within a few months, presto-chango! Any CO2 is completely gone. In white wines, I don't mind residual CO2. In fact, I think they taste flat without it.

[Raptor]

I don't take any steps to forcibly remove CO2 from wine, or measure it, for that matter. I barrel age all my red wines and, within a few months, presto-chango! Any CO2 is completely gone. In white wines, I don't mind residual CO2. In fact, I think they taste flat without it.

so we shouldn't forcibly degass - is that what you are suggesting?

[SleepyDave]

I think that many people find barrel ageing red wine, especially red wine made from fresh grapes, gets rid of all the CO2. Personally, I find great difficulty in getting all the CO2 out of my red wines, especially the kit wines. I'm not even really sure I can tell when I have got enough out, which is why I was interested in some type of measuring instrument. The consensus does seem to be however, that red wines should be fully degassed and I believe that some of the 'rough' flavour of some of my wines has been due to CO2. But I'm not a real fan of white wines and only make a few and had taken the same approach with them as with my reds - ie blitz out every last trace of CO2. Now I think I'm getting a bit more of the picture and white wines seem to need a different approach and the page I quoted above suggests that even light fruity reds taste better with a little more CO2.

[rjb222]

I think that many people find barrel ageing red wine, especially red wine made from fresh grapes, gets rid of all the CO2. Personally, I find great difficulty in getting all the CO2 out of my red wines, especially the kit wines. I'm not even really sure I can tell when I have got enough out, which is why I was interested in some type of measuring instrument. The consensus does seem to be however, that red wines should be fully degassed and I believe that some of the 'rough' flavour of some of my wines has been due to CO2. But I'm not a real fan of white wines and only make a few and had taken the same approach with them as with my reds - ie blitz out every last trace of CO2. Now I think I'm getting a bit more of the picture and white wines seem to need a different approach and the page I quoted above suggests that even light fruity reds taste better with a little more CO2.

With kit wines it is super important to have a wine at a temperature of about 20-23 deg liquid temp when degassing. Whether degassing in a barrel or with a tool or shaking the carboy does not matter. Kit wines hold onto CO2 where a wine made from a juice or grapes will release the co2. Fissy red wine tastes acidic there fore the fruit flavors are muted. This is because co2 is an acid. I have always found that with kit wines less is more as long as the temperature is up when degassing is done. In my business I currently make around 200 to 300 wines per year from kits. When doing the co2 degassing and addition of the stabilizers I watch the lines of CO2 coming off I do not go by a time as suggested in instruction sheets. I can see when to largest amount of co2 is coming off the wine. I stop at that point put on the air lock and put the dj on the shelf. then every time I pass by for about a week I give the dj a shake. I have never had a cork push this way nor oxidised a wine which is a risk when we over degas or get a vortex instead of a flat surface. After that point I can see very little CO2 releasing when I shake the dj I then move the red wine into a cooler conditioning area and allow the sediments to drop out I when these are clear filter and bottle the red wine. With the whites the only thing I do different is I don not give the dj a shake after the initial degassing I want some residual co2 present to help with aroma transfer and give the wine a brightness that a totally degassed white will not have. I find every one has trouble with the degassing part of wine making there is more panic displayed in this area than any other relax if your red wine is a little gassy use a good aerator and give the bottle a good shake before pouring your wine allow your wine to breathe for an hour before serving all these actions go towards flavor enhancement and getting rid of co2 gas.

[SleepyDave]

When doing the co2 degassing and addition of the stabilizers I watch the lines of CO2 coming off I do not go by a time as suggested in instruction sheets. I can see when to largest amount of co2 is coming off the wine. I stop at that point

Hi RJB.
What do you use to do your CO2 degassing? Mechanical or Vacuum?

[NorthernWiner]

so we shouldn't forcibly degass - is that what you are suggesting?

Red wines do need to be de-gassed, but I prefer a minimalist approach in accomplishing that. For my situation, barrels make the most sense. I often make 30-50 gallon batches, and it just isn't feasible to use a pump or stir stick. Nor do I like the idea of beating up the wine like that. I've watched people whip their wine with drill attachments and can't help but think that, in addition to shaking out the CO2, the method is also introducing a lot of unwanted oxygen. I like the idea of putting it in a barrel for 6-12 months and leaving it to de-gas naturally. But I'll concede that won't work for everyone's situation, either because they are making smaller amounts or don't want to make a sizable investment in wooden casks.

[Raptor]

thanks Steve. Maybe my current method of minimal degassing is fine then (ie shaking until most of the fiz has gone)

[rjb222]

I use a degassing tool on a drill. Please remember there is a difference in what I have to do to be able to put out wine within a time line. This has always been a bone of contention between me and my supplier. The instructions give dead lines and people think for what ever reason the instructions are a recipe not a guide line. So I am forced to put out wine in a month to two months that normally would take a year to get done using Steve's methods. When I make my own wine I let things happen naturally even with kit wines it just takes time for the CO2 to dissipate that allows the sediments to drop out and the wine to clear. My mead takes any where fro 10 months to 1 1/2 yrs to get into a bottle darker honeys seem to take longer to get clear for some reason but the mead is so much more flavorful. So to sum up it depends on when you want to serve your wine as to how to get it to the point of being clear. That is not to say the wine will be mature that is a whole different subject.

[SleepyDave]

I have been aware for some time that temperature is a major issue and I have a degassing set up of a 5 gal glass carboy with a heater and a vacu-vin attached. But my red wines are in 5 gal pet carboys in a brick shed where the max temperature so far this year has been around 18C - and the wine inside wouldn't have had much chance to get that high as I've got the carboys insulated and the average temperature was more like 16C. My two year old wines are still full of gas, even those made from grapes.
I'm wondering if I need to give them a few weeks, or even a couple of months, somewhere warmer. And I'm also wondering whether pet carboys are going to let them breathe enough. Perhaps HDPE would be better.

[Cellar_Rat]

HDPE will indeed bring them on quicker.
Not sure though I'd it will help with Degassing.

[rjb222]

HDPE is actually a poor choice to brew in as far as I am concerned. HDPE allows too much oxygen transfer this does nothing for the removal of C0 2 But it will oxidise your wine. They are ok for short term use but long-term such as bulk aging you are asking to ruin your wine. Pet type are a good choice not nearly as much oxygen exposure Glass are the best you can vacuum degas glass without issue.

[Cellar_Rat]

Absolutely.

IMO time is the best degassing tool.

[SleepyDave]

IMO time is the best degassing tool.

I do agree, but I need to free up some storage space ready for this years grapes and every wine I try to bottle still has too much gas in it. My 5 gal PET carboys don't seem to be releasing the gas at all. Steve (Northern Winer) says his wines are degassed after a few months in a barrel. I suspect that temperature is a major issue but I'm not in a position to install half a dozen barrels in the next few months. It looks like my only option for a 'breathable' alternative to PET is HDPE. I propose using a few fermenters for a few months with the temperature at around 23C to see if this has any effect.
I do not want to have to get the electric drill out!