Question on PH and CO2

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You could also get simple pH test strips, fairly cheap (under ten bucks) for 100-pack. I use these only out of curiosity (to learn as I begin tampering with my processes). As I only make wines from kits at this point I do not feel the need to do anything more involved or pricier.
Those test strips aren't really worth a plugged nickel. They are potentially accurate to 0.5 ph and I say potentially due to the error in reading the color change in a red wine. Spend $20-30 and get a cheap ph meter.
 
As long as there’s co2 n the wine then it won’t oxidize. co2 present protects against that.
Where did you read that? There’s always some CO2 present. I believe a large amount of CO2 in solution reduces the solubility of oxygen, but doesn’t remove it.
Fizzy foam will eventually turn into larger bubbles. That’s o2.
I don’t think that's the case. Big bubbles are likely still CO2. I think it was @sour_grapes that had a good explanation of the bubble size. It's all related to surface tension, nucleation sites, CO2 saturation, and the depth that the bubble originates at, I believe. But you are right that it occurs once most of the CO2 has come out of solution.
 
Agreed, the solubility of any gas is related to the partial pressure of the gas above the solution. ,,, essentially percentage ,,, . No we can not change the solubility of atmospheric O2 into our wine (remove it) so we work to have good air locks, seated corks etc. to minimize the percentage of oxygen in the head space and yes there is normally some CO2 dissolved in wine and ready to come out of solution where it can do protective work in flushing the total volume of gas mixture in the head space and as a result decrease the relative percentage of oxygen in the head space. (or go back in solution if we were squeaky clean at degassing 2)
Where did you read that? There’s always some CO2 present. I believe a large amount of CO2 in solution reduces the solubility of oxygen, but doesn’t remove it.
If you search WMT there are several threads which go into gases effect in protection of wine
 
Where did you read that? There’s always some CO2 present. I believe a large amount of CO2 in solution reduces the solubility of oxygen, but doesn’t remove it.

im not talkin in a technical and scientific sense with that. I’m speaking specifically in noob winemaking language.
—**If loaded with co2- no need to sweat oxidation from o2 exposure**—

So throw all the chemistry technicalities out the window. A wine fresh after fermentation is loaded with co2. Overloaded. Until that co2 has dissipated over time you will not oxidize from air exposure. If there was prolonged o2 exposure in a co2 loaded wine— the co2 would dissipate first THEN would oxidize. It won’t oxidize while loaded with co2.

therefore I’m never too concerned with o2 exposure early on. This is also the reason we can get away with not topping up right away. It’s the reason kits instructions don’t advise to top up until the very end at the bottling step.
“if not bottling and choose to age in bulk then dose with so2, and top up with water or similar wine”. Because ther is co2 present and the wine isn’t going to oxidize in those few weeks because of some headspace.

also is why I don’t degas manually. I view co2 as a good thing. Extra protection in the beginning.
Obviously many things factor into how long it lasts. Abv, Acid levels, temps, headspace, so2 etc
I don’t think that's the case. Big bubbles are likely still CO2.

again- strictly noob winemaking terms. I don’t dispute @sour_grapes scientific bubble info. I don’t dispute much anything from sourgrapes unless I’m 100% positive and ready to battle with my A game and some new impressive vocabulary words lol.
Just talking from personal experience degassing. I used to use a drill and also VacuVin pimp. Initially the bubbles generated are white foam/fizz. Looking exactly like head on a beer.
Eventually that fizz becomes less fizzy and more bubbly. When there’s no more fizz generated we have removed as much co2 as we are able. Even if all removed tho you still can generate bubbles. Larger bubbles. I’m saying those larger bubbles = no more degassing is needed.

Simply put, as far as a new winemaker is concerned:
Co2 noticeably present= no worry about oxidation
Degassing= Finished when no more fizz generated
 
im not talkin in a technical and scientific sense with that. I’m speaking specifically in noob winemaking language.
—**If loaded with co2- no need to sweat oxidation from o2 exposure**—

So throw all the chemistry technicalities out the window. A wine fresh after fermentation is loaded with co2. Overloaded. Until that co2 has dissipated over time you will not oxidize from air exposure. If there was prolonged o2 exposure in a co2 loaded wine— the co2 would dissipate first THEN would oxidize. It won’t oxidize while loaded with co2.

therefore I’m never too concerned with o2 exposure early on. This is also the reason we can get away with not topping up right away. It’s the reason kits instructions don’t advise to top up until the very end at the bottling step.
“if not bottling and choose to age in bulk then dose with so2, and top up with water or similar wine”. Because ther is co2 present and the wine isn’t going to oxidize in those few weeks because of some headspace.

also is why I don’t degas manually. I view co2 as a good thing. Extra protection in the beginning.
Obviously many things factor into how long it lasts. Abv, Acid levels, temps, headspace, so2 etc


again- strictly noob winemaking terms. I don’t dispute @sour_grapes scientific bubble info. I don’t dispute much anything from sourgrapes unless I’m 100% positive and ready to battle with my A game and some new impressive vocabulary words lol.
Just talking from personal experience degassing. I used to use a drill and also VacuVin pimp. Initially the bubbles generated are white foam/fizz. Looking exactly like head on a beer.
Eventually that fizz becomes less fizzy and more bubbly. When there’s no more fizz generated we have removed as much co2 as we are able. Even if all removed tho you still can generate bubbles. Larger bubbles. I’m saying those larger bubbles = no more degassing is needed.

Simply put, as far as a new winemaker is concerned:
Co2 noticeably present= no worry about oxidation
Degassing= Finished when no more fizz generated
Very nice explanation, thank you.
 
Very nice explanation, thank you.
I try not to get too wrapped up in the science. Just want enough understanding to be able make confident winemaking decisions. (To keep it real I admit sometimes I’ll nerd out and fall into a rabbit hole of different things like say, mlf studies on sequential vs co-inoculation for example.)

I’ve said this before many times, but I’ll keep on saying it —Learning the hobby from my “Old Style” winemaking family (no tests,additives, so2, concern for o2 etc etc) has helped me tremendously. Knowing how resilient wine can be even if almost every single accepted safe practice is ignored gave unique perspective! Lol.
Rather than say, cutting your teeth on kits. Forcing you to live and die by those instructions often getting hung up on minor details before fully understanding things.

Top 3 things that have helped my winemaking
1.This forum
2. Guide to red winemaking (My Bible!)
3. Growing up with winemaking
 
I’ve said this before many times, but I’ll keep on saying it —Learning the hobby from my “Old Style” winemaking family (no tests,additives, so2, concern for o2 etc etc) has helped me tremendously. Knowing how resilient wine can be even if almost every single accepted safe practice is ignored gave unique perspective! Lol.

Amen. I laugh to think about how utterly stressed I was on the first kit or three. Once I mismanaged the siphon, and (GASP) accidentally touched the vinyl tube before it went into the bucket! Quelle horreur! Should I just give up and throw it away!?!?

I don't feel like searching for it, but remember that old-timey video someone (@GreginND? @ibglowin?) posted of winemaking in, I think, Sicily or Greece or Macedonia, with lots of shovels and pitchforks and FLIES. I think it is okay if you accidentally touch the siphon hose. ;)
 
I really like that video, I'm sure they get the "house" flavor profile, with those conditions there's no need for inoculation with commercial yeast or ML bacteria, and using the copper transfer vessel and funnel reduces the H2S risk. It would be nice to have subtitles, the only part I understood was around the 6:38 mark, the younger guy telling the rest that this is old technology.
 
I would say that's WAY overkill. Especially if you're a beginner and/or making kits. No need to test anything on a kit, unless you are tweaking it. If you are making your own wine, I think as a beginner, the biggest concern would be pH, and a cheap meter would suffice.

It’s also super easy to test it yourself and not worth sending to a lab, i found another article here which might be easier to understand than what i posted. You can basically have 95% of the accuracy of the lab at home. The only reason I test is because i bulk age for extended periods and throw the instructions out Along with the clearing agents, in cases of following the kit instructions KCCam is right just follow what they say and you will make some decent wine. Could it be better? Yes but remember that ”better“ is Subjective and you may just be wasting your time At tweaking when you like the kit/wine already.

https://www.smartwinemaking.com/post/managing-sulfites-in-wine
 
Came up fast on a quick search using the google........




Good god! Repressed memory floodgates opened! I can even smell it.

That says it all! Seeing some version of this as the winemaking norm tends to help keep things in perspective. Seeing LOTS of similarities from my family here and also in Italy.
I spent a month there when I was 16 with my grandpop & brother. We stayed w/ family outside Rome, on the Amalfi coast near Pompei, but mostly on the Adriatic Coast. Family owns an Alfa Romeo dealership/auto shop outside Ascoli Piceno (known for their Melette Anisette D8D86D24-65B0-4672-945D-360DDB71D50F.jpeg) in the beach town San Benedetto called Fratelli Massa.

Every single family we stayed with made their own wine, (and pizza!) and one of their cellars looked exactly like this. I remember thinking the floor troughs & drains looked cool but couldn’t possibly still be used lol. Well I was wrong! One of the coolest things imo was after tasting their wine it was damn near identical to the wine made by us in Philly. For many years we would send bottles to each other until my grandfathers cousin Sentimio eventually passed away.

A few years after my trip my Italian cousin who now runs the auto shop came here and he stayed with us for couple weeks. I took him to a strip club “Show n Tell” 😁. Wild night. But that’s another story for another day.

First time seeing that video. Brought me bacK. Loved it Thanks for posting again.
And if it’s as similar as I think- I’d bet the farm that the rest of the wives are inside preparing an absolute feast for afterwards!
 

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Good god! Repressed memory floodgates opened! I can even smell it.

That says it all! Seeing some version of this as the winemaking norm tends to help keep things in perspective. Seeing LOTS of similarities from my family here and also in Italy.
I spent a month there when I was 16 with my grandpop & brother. We stayed w/ family outside Rome, on the Amalfi coast near Pompei, but mostly on the Adriatic Coast. Family owns an Alfa Romeo dealership/auto shop outside Ascoli Piceno (known for their Melette Anisette View attachment 64617) in the beach town San Benedetto called Fratelli Massa.

Every single family we stayed with made their own wine, (and pizza!) and one of their cellars looked exactly like this. I remember thinking the floor troughs & drains looked cool but couldn’t possibly still be used lol. Well I was wrong! One of the coolest things imo was after tasting their wine it was damn near identical to the wine made by us in Philly. For many years we would send bottles to each other until my grandfathers cousin Sentimio eventually passed away.

A few years after my trip my Italian cousin who now runs the auto shop came here and he stayed with us for couple weeks. I took him to a strip club “Show n Tell” 😁. Wild night. But that’s another story for another day.

First time seeing that video. Brought me bacK. Loved it Thanks for posting again.
And if it’s as similar as I think- I’d bet the farm that the rest of the wives are inside preparing an absolute feast for afterwards!

That is awesome. I have spent some time in Ancona (not far from San Benedetto), but it would have been so great to have more local guidance. Nice!
 
That is awesome. I have spent some time in Ancona (not far from San Benedetto), but it would have been so great to have more local guidance. Nice!
Worth its weight in gold! (Which is hitting all time highs. Keep on printing that money! 👀)

A tour guide can make or break the day. And between my brother and grandfather (both spoke Italian) and various family members I felt very fortunate. We never had to use any actual tour guides. Even had a cousin lend me an extra moped and we hit the Saturday night teenager scene together. (No drinking age!)

My brother would be able to reference things I’d appreciate. Like “see that library over there? Remember when Indiana Jones used the rope-stand to bash the floor tile to get underground? X marks the spot? That’s where he did that!”

And my grandfather was dead set on making a memorable trip, so when not staying with family we stayed at youth hostels —except Venice. That’s where he arranged for us to stay at convent with all the nuns!
 
Also, how long does it take for the CO2 to settle down? Each kit seems a little fizzy still. I have chosen to let them sit in the carboys until I need the carboys this fall so I have another month or two before I bottle. Any help is appreciated

to bring it back on topic after derailing the thread — if leaving carboys undisturbed then that co2 generated from fermentation can linger a while. this is actually how my grandpop would determine when to bottle. They would rack it off the lees and let it age untouched, tasting along the way. Usually sometime in the spring it was co2 free ~6 mos. earliest.
 
This dialog has been incredible, Ajmassa, and I truly enjoyed the video! Back to topic for me.....since I originally posted this I have come across several additional carboys and will let my kit wine sit for at least 6 months before I consider bottling. Sorry...being a noob..... Is the "tipping point" for bottling as simple as when there is no more fizzyness to the wine or is there another "right time" to bottle?
 
This dialog has been incredible, Ajmassa, and I truly enjoyed the video! Back to topic for me.....since I originally posted this I have come across several additional carboys and will let my kit wine sit for at least 6 months before I consider bottling. Sorry...being a noob..... Is the "tipping point" for bottling as simple as when there is no more fizzyness to the wine or is there another "right time" to bottle?
Not at all! I didn’t mean it like that. Was just saying how my very very very old school fam used to do it. cool thing about winemaking is that there’s not really a wrong way. Some people bottle earlier and manually get rid of the co2. Others let time do the job and let the wine age in bulk. Routine racking off sediment every few months also helps that co2 go away faster.

I suppose the longer ya wait the better odds of no sediment in the bottle, clear wine, better idea you have of what it’s gonna be. Leaves options open to tweak if needed, blend or add oak or something. I put it off because 1. I’m a procrastinator. And 2. Once it’s bottled it’s damn near impossible to let it age. The Co2 dissipating and wine clearing are more just a byproduct of that for me
For some it’s a space saving thing. Or freeing up a carboy. Or just antsy. To speed up the process with drilling co2 and clearing agents & basically following kits instructions.
People on this forum are awesome. Really. A true passion for it. And they genuinely enjoy helping others seeking advice.
 
Ive only been doing the wine thing about 7 years and like most, patience is the number one problem. Ive had more than my share of bottle blows! Mostly with "skeeter pee". Since SP is generally in good shape to drink in 3 or 4 months, bottling too early is a big risk. Looks clear, then the oxygen during bottling rejuvenates those little rascals and boom, or a few months later it hazes in the bottom of the bottle.
 
Apologies for resurfacing an old thread, I think I have a CO2 issue with my 2020 wines and this seemed like a good discussion to tag onto rather than starting a new thread.

I have 5 gal of Cab Franc, 6.5 gal of Barbera, and 2x6.5 gal of Zin, all finished primary and ML, and were racked off fine lees and sulfited back in October and put to bed for the winter. When I tested the wines in January, the pH of the Cab Franc was at 3.5 but the Barbera and Zins were around 3.15. So I added potassium carbonate and cold crashed those three, which brought their pH's up to 3.3. So, I thought I was good - racked the wines after cold crashing and left in carboys under solid stopper since the beginning of February. About a month ago, I tasted and tested the wines and everything was still in good shape.

Well, today I tested the wines with a calibrated pH meter and all four of them have seen a fairly consistent .2 drop in pH across all the wines - the Cab Franc is down to 3.3 and the Barbera and Zins are around 3.1. I thought it was odd that the Cab Franc also dropped since I did not cold crash that one. With the drop in pH, the wines are tasting a bit tart.

I racked and sulfited the wines, so I guess I'll find out an answer sooner or later, but I was curious if the drop in pH could be due to built up CO2 since I was using a solid stopper? Could something else cause this change?
 
When I have tested it seems that there is a consistent drop by 0.2 units pH between the primary and next racking. Also there seems to be a 0.1 gain between primary and where the wine is bottled. We can explain the first gain with CO2 build up and get a better reading by degassing as with a cylinder and vacuum or microwave heat followed by stir and cool back to RT.
I do not have an explanation for a net gain on finished wine and am curious what others have seen. To me this translates into reduced SO2 activity which I don’t really like.
. . . with a calibrated pH meter and all four of them have seen a fairly consistent .2 drop in pH across all the wines - the Cab Franc is down to 3.3 and the Barbera and Zins are around 3.1. I thought it was odd that the Cab Franc also dropped since I did not cold crash that one. With the drop in pH, the wines are tasting a bit tart., , , ? Could something else cause this
All high CO2 beverages will taste more tart ,,, for commercial folks we like the marketing term “it is FRESH tasting”, ,,, and some bottlers will take bulk white wine and carbonate it before packaging.
 

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