Question on PH and CO2

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Main man

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Hi:

I posted this on the Beginners side of this forum and received only one reply. I'm hoping someone might see it here and help me.

I started 4 different kits back in early May. Is it normal for the Ph in my kits to rise as they are aging in carboys? My cabernet kit now is at 3.75 an my Zin is at 3.68 which is around a .1 rise in 30 days for each. I'm wondering if this is normal or what may be causing this and what I can/should do to correct it? 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
 
Hi:

I posted this on the Beginners side of this forum and received only one reply. I'm hoping someone might see it here and help me.

I started 4 different kits back in early May. Is it normal for the Ph in my kits to rise as they are aging in carboys? My cabernet kit now is at 3.75 an my Zin is at 3.68 which is around a .1 rise in 30 days for each. I'm wondering if this is normal or what may be causing this and what I can/should do to correct it? 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
Kits are designed by the manufacturers to satisfy 99% of their customers when following the directions word for word. There are lots of tweaks you can make once you understand the chemistry and art involved, but even @cmason1957 (who is very accomplished, and respected here) says he generally doesn't check the pH of his kit wines. Since you have a pH meter (most beginners don't -- I don't (yet)), I would use it to make notes. Keep a record of the pH before pitching the yeast, and then at every SG check. Taste along the way. Don't adjust anything in a kit until you have a good idea of how it was intended to turn out. Then start tweaking. You'll have a baseline to compare to.

As far as how long will it take the CO2 to settle down? That's like asking how long will it take wine to ferment. Too many variables to even guess most of the time. The 3 most common ways (to my knowledge) to help degas your wine are: stirring vigorously in the carboy (as kit directions might suggest), applying a vacuum (as a lot of us do with our AIO pumps), and time. I've read comments about wines that are still a bit fizzy after 3 months. With my AIO pump, my last 2 batches of Dragon Blood were done in a day.
 
which is around a .1 rise in 30 days for each

You are probably already properly cleaning the electrode after use, storing it in the right solution, and calibrating the meter before each use. But it's worth stressing those since I've noticed my pH electrode drifting as much as 0.2 over a month between calibrations.
 
Hi:

I posted this on the Beginners side of this forum and received only one reply. I'm hoping someone might see it here and help me.

I started 4 different kits back in early May. Is it normal for the Ph in my kits to rise as they are aging in carboys? My cabernet kit now is at 3.75 an my Zin is at 3.68 which is around a .1 rise in 30 days for each. I'm wondering if this is normal or what may be causing this and what I can/should do to correct it? 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

I suspect that it’s not that your wine pH is rising as it ages, but is instead your meter is becoming more correct as your wine degasses. Your meter is being tricked by CO2 into thinking the pH is lower than it really is.

Once alcoholic fermentation begins, so does the production of CO2, which quickly saturates the liguid. As long as CO2 is present in your wine, readings from a pH meter will not be accurate. When we want accurate pH readings from carbonated wine, it must be degassed first. Take a small quantity of wine and heat it into the 90’s, put it into a test tube or similar vessel, cover the open end, and shake it, then remove your finger to release gas Repeat until there is none. Now run your pH test.

This is a completely normal situation, we face it with kits, grapes, fruit wines, frankly, anything you can ferment. The length of time it takes your wine to release all of its CO2 isn’t a standard time, all wines are different.
 
This is great! Thank you all for the information. I want to bottle in a month or two. Do I need to be concerned with the amount of CO2 still in it when I bottle?
 
This is great! Thank you all for the information. I want to bottle in a month or two. Do I need to be concerned with the amount of CO2 still in it when I bottle?

If you bottle it with CO2 still in, you will have fizzy wine, when you pop those corks and it won't be good as long as it might. That CO2 also impacts the taste and not in a really good way.
 
Hi:

I posted this on the Beginners side of this forum and received only one reply. I'm hoping someone might see it here and help me.

I started 4 different kits back in early May. Is it normal for the Ph in my kits to rise as they are aging in carboys? My cabernet kit now is at 3.75 an my Zin is at 3.68 which is around a .1 rise in 30 days for each. I'm wondering if this is normal or what may be causing this and what I can/should do to correct it? 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

Ive never used my PH meter so far it’s just been sitting there, I usually have a nice number of what I want for sulfites before bottling which is hovering somewhere just under 50PPM for most. Is there any particular reason as to why you are checking PH though if you’re not testing for sulfites? Regarding the fizz, I use a wine whip on a drill quickly switching directions back and forth for 4 minutes. It typically removes most of the CO2 but there always seem to be A slight amount Left, the batches I haven’t bulk aged for more than 6 months sometimes end up bottled with fizz. It will slow down bottle aging, however if you decant the wine before serving or shake up the bottle before serving it will remove it. If not removed in a red it will make it taste bitter and throw everything else off. Some guys use a vacuum pump Which works better, ive also heard of carboys imploding though so I just stick to a wine whip and bulk aging for at least 6 months. Fizz in a white wine though is actually okay and desired in some cases, you can typically get away with a little bit. It also helps protect the white wine since it’s more delicate than red.
 
I suspect that it’s not that your wine pH is rising as it ages, but is instead your meter is becoming more correct as your wine degasses. Your meter is being tricked by CO2 into thinking the pH is lower than it really is.

Once alcoholic fermentation begins, so does the production of CO2, which quickly saturates the liguid. As long as CO2 is present in your wine, readings from a pH meter will not be accurate. When we want accurate pH readings from carbonated wine, it must be degassed first. Take a small quantity of wine and heat it into the 90’s, put it into a test tube or similar vessel, cover the open end, and shake it, then remove your finger to release gas Repeat until there is none. Now run your pH test.

This is a completely normal situation, we face it with kits, grapes, fruit wines, frankly, anything you can ferment. The length of time it takes your wine to release all of its CO2 isn’t a standard time, all wines are different.

Sorry to be picky but as a Chemist- the pH meter is not becoming more correct, is is reading the actual pH of the wine at each point in time assuming it is properly calculated. Dissolved CO2 is an acid so the wine is indeed at a lower pH while the CO2 is in there as the wine degasses the pH will go up.

Also to be noted the pH reading will also be affected by temperature if your meter does not have ATC (Automatic Temperature Correction).
 
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Sorry to be picky but as a Chemist- the pH meter is not becoming more correct, is is reading the actual pH of the wine at each point in time assuming it is properly calculated. Dissolved CO2 is an acid so the wine is indeed at a lower pH while the CO2 is in there as the wine degasses the pH will go up.
Understood, I was just trying to make it a bit more understandable for the OP. The meter does indeed read the actual pH at the time a reading is made. It’s not the same pH the wine will ultimately be with no CO2 on board.
 
Great information! Thank you. I'm at 3 months roughly on the kits. If I attempt to degas now in the carboys, don't I run the risk of oxygenating the wine?

I need to look into how to test for sulfites. I have not figured out all the chemistry yet. What do I need to test for sulfites?
 
The easiest way to check SO2 is with a vinmetrica. Wet chemistry is a pain unless you have a commercial lab with all the toys/ glassware. ,,,, If you are doing whites and fruit wine a quick and dirty guess is it will test at 0 or a trace SO2. Reds? I don’t have enough experience,

For years I have seen judged wine with a hint of bubbles on the glass, the teams sometimes note this but normally do not dock the sample. Looking at samples with slight bubble formation I have so far always been able to produce nicely defined bubble release by applying a light 5 or 10 inch vacuum.
My feeling about CO2 changed last year at Winemaker conference, it is reductive which helps protect the wine from oxidation/ fill the head space therefore I don’t look and say I need to be squeaky clean. ,,, (I am a recovering no bubble person)

Back to carbonation from posts above ,,, a few examples:
cream soda. , , , . , , W 3.10. WO 3.14
beer. , , , , , , , , , , , , W 4.30. WO 4.37
Cola soda. , , , , , , , W 2.49. WO 2.49 (a phosphoric acid system)
citrus soda. , , , , , , W 2.98. WO 3.04 (a citric acid system)
sparkling water. , , , W 3.5. WO 7.2 (a non buffered system)
Brachetto (6%OH). , W 3.36. WO 3.34 (carbonated Italian grape)

..... the change seems to be more obvious in a drop on TA when carbonated ,,, ie the manufacturer does it for flavor impact more than pH. ....
 
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Great information! Thank you. I'm at 3 months roughly on the kits. If I attempt to degas now in the carboys, don't I run the risk of oxygenating the wine?

I need to look into how to test for sulfites. I have not figured out all the chemistry yet. What do I need to test for sulfites?
Not necessarily, When you whip the wine you should do so in a controlled manner and switch directions every 20 seconds or so to prevent a vortex from forming. You are really just agitating the CO2 from the wine, where the bulk aging should take care of the rest. You also have the CO2 protecting the wine aswell. If you let it bulk age for 10 months or so racking a few times that could also take care of the CO2. How much sulfite have you added up to this point? You want to make sure you have at least added 4G to 4.5G or so when the fermentation was done before you do any racking or stick a wine whip in there. You could also try the vacuum method, however most of my carboys are used from thrift stores and garage sales since i have about 20 of them...I’m not sure i would trust any of my carboys to not implode on me from the pressure ruining the wine, my floor and potentially injuring me. Also some CO2 is ok especially for whites as mentioned above, you may not necessarily taste it on your tongue but if you shook the bottle you could hear it. Decanting and sloshing/aerating also gets rid of it. If your carboys are new it could be worth a try, there are a ton of different cheap methods to google rather than buying a pump.

As for testing sulfites, you don’t need a Lab just some chemicals and graduating beakers. The cheapest and most accurate way to do this at home is with the Oxygen aeration method. If you live in the USA everything should be pretty easy to get. I live in canada and its a little harder but i get everything from BOSA Grape in western canada and i made all the fittings i needed rather than buying it direct from Morewinemaking.com Which would not sell their kit across the border due to the chemicals. If you do live in the USA just simply buy their Mt140 kit. If you do not buy their kit you can use their instruction online either way. You will have to re-purchase some of the chemicals every 6 months as they have a shelf life, but its pretty cheap when you average your overall wine cost for the year.

In a nutshell for testing sulfites you have Two beakers (1 and 2). Beaker 1 has a measured sample of wine (20ML) and phosphoric acid(10ML). Beaker 2 has hydrogen peroxide(10ML, drug store type), distilled water(40ML) and a S02 indicator (6 Drops) which changes color depending on how acidic or base the solution is (Pink for acidic, grey for neutral, green for base). Beaker 2 gets a tube going down into its solution, the other end gets placed Just past the top of beaker 1 But not in the solution. Beaker 1 than gets another second tube but down into the solution this time with the other end going into a cheap aquarium pump. Note that beaker 1 needs to be sealed tight, the best way is to purchase or drill your own rubber bungs And feed the tubes through it so you can seal up your beaker around the tubes. Let the pump run for 15-20 minutes, during this time the wine solution mixed with the phosphoric acid and bubbling from the pump turns the sulfites in the wine into sulfuric acid and forces it into the beaker with the indicator solution through the tube. When this is done you are left with the indicator solution/distilled water/hydrogen peroxide in beaker 2 which should now be pink, now you add sodium hydroxide at very small intervals or drops to change the now pink solution back to a baseline color of greenish grey. Each 1ML addition required of sodium hydroxide to bring it back to the base color gets multiplied by 16 which will indicate how much free sulfite is protecting your wine. It sounds complicated but its not, i not a chemist in fact i hated chemistry in school. The vinmetrica is an electronic method which still required chemicals that have a shelf life, its both more expensive and less accurate.

I should do a YouTube video, i wish i had that when i first started testing. It’s much more complicated to explain than the actual process which is otherwise easy.
 
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Great information! Thank you. I'm at 3 months roughly on the kits. If I attempt to degas now in the carboys, don't I run the risk of oxygenating the wine?

I need to look into how to test for sulfites. I have not figured out all the chemistry yet. What do I need to test for sulfites?
As long as there’s co2 n the wine then it won’t oxidize. co2 present protects against that. So you can drill it up getting that white co2 fizz. Let it dissipate and drill some more till it’s gone. Higher temps make this easier. Fizzy foam will eventually turn into larger bubbles. That’s o2. - that means you are done—or you could just wait and let nature run it’s course too.

Testing Ph for sulphites on kit wine isn’t really necessary. You can safely add 1/4tsp per 5-6gal and not worry about it. Kits acids are pre-balanced so shouldn’t have any curveballs to account for If ya really wanted to test anyway there’s an easy & cheap way using titrets.
https://www.winemakingtalk.com/threads/cheaply-testing-so2.66043/
 
As long as there’s co2 n the wine then it won’t oxidize. co2 present protects against that. So you can drill it up getting that white co2 fizz. Let it dissipate and drill some more till it’s gone. Higher temps make this easier. Fizzy foam will eventually turn into larger bubbles. That’s o2. - that means you are done—or you could just wait and let nature run it’s course too.

Testing Ph for sulphites on kit wine isn’t really necessary. You can safely add 1/4tsp per 5-6gal and not worry about it. Kits acids are pre-balanced so shouldn’t have any curveballs to account for If ya really wanted to test anyway there’s an easy & cheap way using titrets.
https://www.winemakingtalk.com/threads/cheaply-testing-so2.66043/

PH relates directly to sulfite levels, however I don’t really test For PH either. I’m typically hovering around the max sulfite level that will pretty much protect anything, which is around 50PPM When i bottle. I cannot taste it it at that level so I don’t bother testing PH in kits. Titrations are horribly inaccurate for reds, they are also cost a lot more than the Aeration oxygen method Over time. 1/4 TSP for sure is enough, however I’ve found that when it comes time to bottling sometimes i have way too much which is why I started testing and in many cases I’m skipping the final dose prior to bottling. Unfortunately there are too many factors that prevent duplicating sulfite levels to try and guess what it is, even down to the type and style of stopper used and the manufacturing tolerances in the carboy necks. So one does not have to test...true but its the only method to guarantee your wine wont come out with a sulfite aroma.
 
Thanks everyone.

Ajmassa said "Higher temps make this easier". I have my carboys in a home built cooling area that is chilled by an air conditioner. It seems to hold right at 65 degrees. If I move them out just to degass, what is considered a higher temp? I'm in Nor Cal and it is supposed to be around 107 for a couple of days. Is there an optimal temp?

Also, are there reasonably priced testing labs out there that you can send samples into? If anybody can recommend one, I would appreciate hearing about it. I don't have a lab near me that would do that type of testing.
 
Thanks everyone.

Ajmassa said "Higher temps make this easier". I have my carboys in a home built cooling area that is chilled by an air conditioner. It seems to hold right at 65 degrees. If I move them out just to degass, what is considered a higher temp? I'm in Nor Cal and it is supposed to be around 107 for a couple of days. Is there an optimal temp?
Anything above room temperature I think. When the wine is cooler like in the mid 60’s or lower it makes a portion of the co2 stubborn and impossible to release. But at say 75° you’ll notice the wine much more agreeable to degassing.
 
are there reasonably priced testing labs out there
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.
 
Thanks everyone.

Ajmassa said "Higher temps make this easier". I have my carboys in a home built cooling area that is chilled by an air conditioner. It seems to hold right at 65 degrees. If I move them out just to degass, what is considered a higher temp? I'm in Nor Cal and it is supposed to be around 107 for a couple of days. Is there an optimal temp?

Also, are there reasonably priced testing labs out there that you can send samples into? If anybody can recommend one, I would appreciate hearing about it. I don't have a lab near me that would do that type of testing.

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.
 

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