Ascorbic acid removal from finished wine

[MiBor]

I have a 6 gallon batch of Merlot made from grapes, last year. The fermentation was difficult and, for some reason, I ended up with H2S in this wine. I splashed racked it, I treated it with Reduless and I thought that the problem was resolved. The wine completed MLF in the spring, I racked it a couple of times and there was no sign of H2S anymore. I let it age in a glass carboy since April.

I went to check on it at the beginning of August and, to my surprise, I could smell the rotten eggs again. I tasted it and it also had the reductive flavors that mercaptans would produce, so I decided to treat it with ascorbic acid and Reduless. I found the AWRI page (Disulfides paragraph) for that and followed the procedure, except that I used 20mg of ascorbic acid per liter instead of 2mg (I went and got new reading glasses when I realized what I did). The process worked and now my wine smells great and all the reductive flavors are gone, but it has a sharp acidic note that it didn't have before, from the extra ascorbic acid I added to it.

This is a problem and I'm trying to figure out if there is any way I can correct it. I looked at all the usual acid reducers, K, Na and Ca carbonates and bicarbonates, but all seem to affect mostly the tartaric acid when used in wine. That's another problem because this wine had a pH of 3.78 and a TA of 0.45% prior to my ascorbic acid addition. If I use any of them, the tartaric acid will be reduced even more and I'm afraid that the wine's character will greatly suffer.

I've read somewhere that ascorbic acid reacts with chlorine and the two substances neutralize each other. Does anyone know if that's true and how to do that in wine? Is there another way to remove the excess ascorbic acid from wine without affecting tartaric acid too much?

 

[winemaker81]

I recall reading of a treatment for excess ascorbic acid, but cannot locate it. IIRC, it wasn't one of the carbonates or bicarbonates.

Pinging @Rice_Guy, as I seem to recall him mentioning it (although my memory is faulty).

 

[Rice_Guy]

@MiBor Your wine is a soup of ions which will share H+. As such if you add one of the carbonates or K bicarbonate which you mentioned you can reduce the total acidity. What is your TA after the AWRI treatment? (0.55?,,, 0.6? in the Midwest we would be happy there) Specifically looking for the ascorbic ion it will react quickly with organics in your system and will be in the 1% or 0.1% of treatment level. Time will consume ascorbate ions.

I would not add chlorine to the wine! When one supplier started using chlorine in his ingredient I could read the consumer complaint line to find terms as “chemical” or “medicinal”.

 

[winemaker81]

Last night, after posting, I read one reference that said the ascorbic acid ions dissipate with time, reinforcing David's comment. Give the wine another 3 months to see if it's better. Your wine may be best is it's given another year anyway, so time is your friend.

 

[MiBor]

Thank you @winemaker81 and @Rice_Guy for your prompt responses. It makes sense that you can't remove one acid in the "wine soup" without affecting the others. I won't use chlorine, but I was curious if maybe there was a technique based on it that is being employed by commercial wine makers that I didn't know about.

I checked the wine a week after the ascorbic addition and it had a TA of 0.55% and a pH of 3.64. I know that chemically, these are great numbers for a red wine, but I guide my winemaking more by taste, if the basic chemistry is in the ballpark.

I believe that time can mellow out the sharp note in this wine. I tasted it again and it already seems better. I will let it sit 'till Christmas and assess the taste then. I get a few days off around the holydays and I can bottle it at that time if it tastes better. On top of that, it will get an additional 6 months in the bottle before attempting to drink it, so that will be plenty of time for this wine to "put itself together".

I think I've learned a valuable lesson, though. I will triple-check my numbers and measurements before adding anything to any wine from here on out.

 

[winemaker81]

It's funny how so many things in winemaking come back to the "P" word.

If you haven't, record your impressions now. At Christmas do another tasting, and post both notes. This is good stuff!

 

[Rice_Guy]

. . , a technique based on it that is being employed by commercial wine makers that I didn't know about.

Well you could try an ion exchange cartridge, what I have read is that there is flavor loss,,, OK if it pulls VA out, ,, but it is not a tool with finesse.

 

[mikewatkins727]

@MiBor, you are correct that ascorbic acid reacts with chlorine and will neutralize each other. I have used it to remove the taste of chlorine in water for my wife. It took 0.5mg of the vitamin c per gallon of water. It would be too risky to try this with wine. The safest way is to follow the patience principle.

 

[MiBor]

I will write un update on this wine at the end of the year. I saved my tasting notes on a cardboard tag that I tied around the neck of the carboy, so they will be right there when the time comes for comparison. I do this with most of my wines, to collect taste impressions as they are evolving and maturing in bulk. I also keep notes on my PC about my wines, as they age in bottles. I've learned a lot by doing this and my palate got trained to recognize flaws or qualities I couldn't have noticed before.

I think I may have become too critical and "picky" in a way, because a few friends tasted my Merlot today and said that it was really good and they couldn't find that sharp acidic note I was talking about.

Lastly, I followed a link to Bryan's website today and I read his notes about making a big red wine. He wrote: "Home winemakers are not going to make a 100 point wine. If major wineries with the best fruit, the most highly trained and experienced winemakers, and the best equipment cannot consistently do it, neither will you". Thanks, Bryan. I needed someone to remind me about that...

 

[Rice_Guy]

Another part is your audience. I put the same wine in several contests and will get different ratings with different judges. ,,, Food panels are bad for giving consistency, the real test is will you buy the product again or at a club meeting will someone take a second glass?

 

[qasimbashir6242]

I have a 6 gallon batch of Merlot made from grapes, last year. The fermentation was difficult and, for some reason, I ended up with H2S in this wine. I splashed racked it, I treated it with Reduless and I thought that the problem was resolved. The wine completed MLF in the spring, I racked it a couple of times and there was no sign of H2S anymore. I let it age in a glass carboy since April.

I went to check on it at the beginning of August and, to my surprise, I could smell the rotten eggs again. I tasted it and it also had the reductive flavors that mercaptans would produce, so I decided to treat it with ascorbic acid and Reduless. I found the AWRI page (Disulfides paragraph) for that and followed the procedure, except that I used 20mg of ascorbic acid per liter instead of 2mg (I went and got new reading glasses when I realized what I did). The process worked and now my wine smells great and all the reductive flavors are gone, but it has a sharp acidic note that it didn't have before, from the extra ascorbic acid I added to it.

This is a problem and I'm trying to figure out if there is any way I can correct it. I looked at all the usual acid reducers, K, Na and Ca carbonates and bicarbonates, but all seem to affect mostly the tartaric acid when used in wine. That's another problem because this wine had a pH of 3.78 and a TA of 0.45% prior to my ascorbic acid addition. If I use any of them, the tartaric acid will be reduced even more and I'm afraid that the wine's character will greatly suffer.

I've read somewhere that ascorbic acid reacts with chlorine and the two substances neutralize each other. Does anyone know if that's true and how to do that in wine? Is there another way to remove the excess ascorbic acid from wine without affecting tartaric acid too much?

Hello,

It sounds like you've been through quite a process with your Merlot wine. Dealing with reductive off-flavors and correcting them can be challenging, especially when unintended side effects arise.

Regarding your question about reducing the excess ascorbic acid in your wine without affecting the tartaric acid too much, here are a few suggestions:

Aeration: You might consider aerating the wine by decanting it or transferring it between containers with some splashing. This can help to release some of the excess ascorbic acid as gas, although it might also contribute to slight oxidation. Monitor the wine's flavor as you aerate to ensure it doesn't go too far.

Chlorine Reaction: While ascorbic acid can react with chlorine to neutralize each other, adding chlorine or chlorinated products to wine is generally not recommended due to the potential for off-flavors. It's safer to avoid introducing chlorine to your wine.

Blending: If you have other wines on hand, you might consider blending a small portion of your over-acidified Merlot with another wine to help balance out the acidity. Be cautious and do some small trials before blending larger quantities.

Professional Analysis: If you're concerned about the wine's balance and overall character, you might consider seeking professional analysis from a winemaking laboratory. They can provide insights into the wine's composition and recommend specific actions based on the current chemical makeup.

Time: Sometimes, giving the wine more time to mellow and integrate can help smooth out sharp acidic notes. Aging in the bottle might allow the wine's components to come together more harmoniously.

Before taking any action, it's always a good idea to conduct small-scale trials to see how your chosen method affects the wine's taste and profile. Remember that each wine is unique, so there might not be a one-size-fits-all solution. Consulting with experienced winemakers or enologists can also provide valuable guidance tailored to your specific situation.

Best of luck in finding a solution that preserves the character of your Merlot while addressing the excess ascorbic acid issue.

Best regards,

 

[winemaker81]

I think I may have become too critical and "picky" in a way, because a few friends tasted my Merlot today and said that it was really good and they couldn't find that sharp acidic note I was talking about.

Sometimes we are our own worst enemy, judging ourselves (and our own efforts) too harshly. I sometimes have to remind myself to drop my preconceptions and take things as they are.

Later in that section of my post that you referenced, I wrote the following:

If I can’t make a 100 point red, what can I make? The realistic answer is the best wine I can, that is a good example of the type.​

I have my fingers crossed that a year from now you'll be happy with the wine.

 

[Rice_Guy]

Sometimes we are our own worst enemy, judging ourselves (and our own efforts) too harshly.

@MiBor over this thread I have wondered if you are a super taster? When I was on the lab bench there were two gals in the next lab who could correctly rank 0.1% substitution of mushroom in a formula. Most folks couldn’t. Today I know a couple who can pick out green notes on the stems when eating mulberries. Most folks can’t.

For the average food consumer the question is, ,, “is this pleasing?” and a lot of that can be influenced by advertising/ what one’s peers like. I occasionally will take a wine to a club meeting and be surprised that a common defect as VA won’t be picked up or the less common mercaptan flavor called tastes like “fried chicken“ or “this would be good with chocolate”.

 

[winemanden]

I have wondered if you are a super taster?

My daughter is a super taster, she goes tasting for a testing company, and they classified her as 'Super'.
My wife used to be the same, but unfortunately since this covid business her sense of smell comes and goes. She used to be my chief taster, and could pick out things that were beyond me.
For instance, I very often add some banana gravy to my country wines, it seems to help clear them and add a bit of body. One quick sniff, and she would say "Banana". Me, nothing!
Never mind, she still enjoys drinking wine!

 

[MiBor]

I don't know if I'm a "super taster" or not, but if having strong visceral responses to certain subtle flavors that others don't even notice qualifies me as one, than I may be one.

I didn't use to be like this, but I've had covid a couple of times and I've lost my sense of smell and taste for a few months. I didn't get them back until I bumped the back of my head really hard one day, and that's when they came back with a vengeance. It was like getting a 75" 8K OLED TV after dumping your old 24" black-and-white CRT TV set, in visual terms.

I didn't know what to do with my enhanced senses. I thought it was just a phase in recovery, and they will dull out soon, but that hasn't happened yet. I started liking foods I never cared for, and I was grossed out by others that I've literally ate all my life. Texture became important to me as well, and also a deciding factor if I was going to put something in my mouth or not.

I guess that's why I may be over critical of my wine.

Regardless, I will apply the patience factor and wait until the end of the year to see how my wine will evolve. I'm curious if the reductive flavors are gone for good, or if they will come back again. That will be the deciding factor if I will keep the Merlot or if I dump it.

 

[qasimbashir6242]

I don't know if I'm a "super taster" or not, but if having strong visceral responses to certain subtle flavors that others don't even notice qualifies me as one, than I may be one.

I didn't use to be like this, but I've had covid a couple of times and I've lost my sense of smell and taste for a few months. I didn't get them back until I bumped the back of my head really hard one day, and that's when they came back with a vengeance. It was like getting a 75" 8K OLED TV after dumping your old 24" black-and-white CRT TV set, in visual terms.

I didn't know what to do with my enhanced senses. I thought it was just a phase in recovery, and they will dull out soon, but that hasn't happened yet. I started liking foods I never cared for, and I was grossed out by others that I've literally ate all my life. Texture became important to me as well, and also a deciding factor if I was going to put something in my mouth or not.

I guess that's why I may be over critical of my wine.

Regardless, I will apply the patience factor and wait until the end of the year to see how my wine will evolve. I'm curious if the reductive flavors are gone for good, or if they goku tu will come back again. That will be the deciding factor if I will keep the Merlot or if I dump it.

Whoa, that's a fascinating journey you've been on with your senses! It's like you've got a whole new lens (or should I say palate) through which to experience the world. The 75" 8K OLED TV analogy really drives the point home, haha.

I've heard of taste and smell changing after illness, but this is next level. And that bump on your head acting like a 'reset button' is something straight out of a sci-fi story! I can't even begin to imagine how different your food and drink experiences must be now.

The way you've become sensitive to texture as well? That's so intriguing. It's amazing how your sensory preferences flipped like a switch, both a curse and a blessing, I suppose.

As for the wine, it makes total sense why you'd be so critical. When you've got 8K OLED taste buds, every nuance is going to stand out, right? I'd say giving it until the end of the year is a good call. If the reductive flavors come back, then maybe it's time to part ways with the Merlot.

Super curious to hear how it turns out for you. Cheers and here's to your enhanced sensory journey!

 

[MiBor]

I want to provide an update to the evolution of my acidic Merlot.
I let it sit in the carboy undisturbed until January 5th when, along with a few friends I opened it up and tasted it. I asked everyone present there to give me their honest opinion and everyone said it was great. To me, it tasted as acidic as it was back in August.
I decided to not tell anyone my tasting impressions and to just bottle it. I added 4oz of glycerine to the carboy, which smoothed out the acid a little bit. I stored the 30 bottles separately so I can start giving them away to the people who said they liked the wine. I'm not convinced that this was not a prank that my friends were trying to pull on me, but in case it was, they will get the Merlot and I'll keep the other wines I made for myself. The Cab and Syrah, which I made at the same time as the Merlot, both taste great and I'm getting ready to bottle those as well.

 

[wood1954]

I don't know if I'm a "super taster" or not, but if having strong visceral responses to certain subtle flavors that others don't even notice qualifies me as one, than I may be one.

I didn't use to be like this, but I've had covid a couple of times and I've lost my sense of smell and taste for a few months. I didn't get them back until I bumped the back of my head really hard one day, and that's when they came back with a vengeance. It was like getting a 75" 8K OLED TV after dumping your old 24" black-and-white CRT TV set, in visual terms.

I didn't know what to do with my enhanced senses. I thought it was just a phase in recovery, and they will dull out soon, but that hasn't happened yet. I started liking foods I never cared for, and I was grossed out by others that I've literally ate all my life. Texture became important to me as well, and also a deciding factor if I was going to put something in my mouth or not.

I guess that's why I may be over critical of my wine.

Regardless, I will apply the patience factor and wait until the end of the year to see how my wine will evolve. I'm curious if the reductive flavors are gone for good, or if they will come back again. That will be the deciding factor if I will keep the Merlot or if I dump it.

Weird. I had a neighbor and a sister-in-law who both had hit the back of their really hard and they completely lost their sense of smell.