What causes my wine to be sour? and

[Snafflebit]

Haha, okay it seems like all I do is field complaints on Winemaking Talk. First my wine was bitter, now it is sour. (the other wine is no long bitter BTW)

I will get some numbers posted, but what I did for 2022 vintage is backwater and acidify to a level to reach 4.8 g/L TA. Which I feel was being conservative.

I am currently running chromatography and will measure pH of the wines.

The tartness sort of hits in the back of my throat. I am a little worried it is VA, but I am not smelling vinegar or nail polish. Although the wine was under airlock, I was unable to stay on top of the SO2 since racking off gross lees. The "wine cellar" was covered by a record snowstorm and I could not get into it until April.

I know tannins will mellow with time, but will acid mellow?

Do other winemakers balance the acid by lightly backsweetening? Seems like it could work.

I have been playing with some other aging tannins also. I tried Quertanin Sweet and really like the results in another wine where it created the perception of sweetness.

 

[salcoco]

suggest making a sweetener two cups sugar to one of waiter, take a number of wine samples either 60 or 100ml. add sugar in 1/4 tsp increments to the sample ie first -1/4p; second sample 2x 1/4p; 3rd sample 3x 1/4 sample do taste tests. repeat in 1/4 tsp increments as necessary, once identified calculate for main body add sorbate once sweetener is added

 

[ibglowin]

Sounds like a perfect case of low pH and high TA to me. The pH will be a good datapoint here. Unfortunately if that is the case time will not help it. Your solution(s) are

1) Dilute it with a wine with high pH and low TA to help balance both wines out

2) Drop some Tartaric acid with Potassium Bicarbonate which will raise the pH and lower the TA

3) Cover up the sour taste with simple syrup

 

[Snafflebit]

Step 1. All of my wine samples are now tested for ML completion. It's looking good, but I am rusty on setting up the experiment. I made my spots too large but it still worked. And my tartaric standard was dried out, so I crossed my fingers and made my own from my available chemicals. It's not perfect but I know the lowest marks are tartaric in my test samples and I may see a shadow of malic in the samples, or it is just artifacts of the test. I think that my MLF is complete. And, it is time to buy a refill for my kit.

 

[Snafflebit]

Step 2: I measured pH tonight. There are a few outlier wines like the 3.33 pH, but there are no wines with crazy low pH
I may simply have a taste for the wines in the 3.8 range.

All of the 2022 wines I adjusted to 4.8 g/L TA but ended up with quite a spread in pH.

I think for 2023 I am just makin' wine the old way, no acid, no water, just let nature reign.

serial number	pH measured	type
1	3.48	2022 Meth Merlot FR
2	3.50	2022 cab/merlot blend press frac leftovers
3	3.75	2022 GW Cab FR 80% 2022 Meth Cab FR 20%
4	3.49	2022 Meth Merlot FR
5	3.57	2022 Meth Cab FR
6	3.83	2022 GW Cab FR
7	3.42	2021 Meth Cab
8	3.33	2021 Meth Merlot
9	3.33	2021 Meth Cab green
10	3.58	2021 GW Cab
11	3.56	2021 GW Cab

 

[Rice_Guy]

The tartness sort of hits in the back of my throat. I am a little worried it is VA, but I am not smelling vinegar or nail polish. Although the wine was under airlock, I was unable to stay on top of the SO2 since racking off gross lees. The "wine cellar" was covered by a record snowstorm and I could not get into it until April.
tannins will mellow with time, but will acid mellow? . . . .
Do other winemakers balance the acid by lightly backsweetening? Seems like it could work.
I have been playing with some other aging tannins also. I tried Quertanin Sweet and really like the results in another wine where it created the perception of sweetness.

* many of us add a trace of sugar to balance the flavor, northern grapes will frequently come in at 0.7 to 1.0% TA so we have to. However you live with a better quality crop.
* mellowing? there seems to be some decrease in TA with years of age. I haven’t seen articles that track it. A guess is that an acid will slowly combine with an alcohol creating an ester and pulling the acid out of the system. If you plan to have some long shelf life bottles we suggest in the club add more acid to that set.
* many tannins contribute an acid note, if you look what is washing over the taste buds there is a sweet note that should be out by 30 seconds > there is a slower acid wave say 15 seconds to 45 seconds > there is another wave that is tannin which gives lasting flavors, initially it combines with acid taste buds but it transitions to either bitter (small size tannin complexes) or to astringent/ scraping the roof of the mouth (larger tannin complexes). You can neutralize to pH 6 or 7 to remove the acid taste and train yourself to recognize the tannin
* oxidized ethyl alcohol at low level gives a dried apricot type note, sharp sort of like acid
* VA is easier to pick out of the aroma on a warm sample, try 10 or 20 seconds in a microwave,, swirl and smell
* within the narrow pH range typical in wine the acid sensation is a linear function of TA. If you use a wider pH range as cola sodas pH increases the sensation

Flavors are complicated and will change based on what you just were eating.

 

[ibglowin]

Waaayyyyy to much sample on these. You more than likely have cross contamination sample to sample. Are you using the supplied glass capillary pipettes? All you need is a single tiny drop from that for your sample. Also no need for a Tartaric spot once you know what the spot is. Just the malic and your wine. The blob looks to be complete though!

Step 1. All of my wine samples are now tested for ML completion. It's looking good, but I am rusty on setting up the experiment. I made my spots too large but it still worked. And my tartaric standard was dried out, so I crossed my fingers and made my own from my available chemicals. It's not perfect but I know the lowest marks are tartaric in my test samples and I may see a shadow of malic in the samples, or it is just artifacts of the test. I think that my MLF is complete. And, it is time to buy a refill for my kit.

View attachment 103064

 

[ibglowin]

Oh and a pH of 3.3 if that is correct would be low enough to taste bitter/sour on the tongue. Been there. Done that......

 

[Snafflebit]

@ibglowin It's been a while since I have run a ML test. the glass pipettes were used, but the artist has large brush strokes

I will probably experiment with all three suggestions: blend with low acid wines, drop some acid with bicarbonate, and backsweeten.

I have never tried to titrate a wine

 

[Snafflebit]

Step 3. Bench trials.

I am tasting the wines side by side in a quiet, relaxing space. Maybe all I am missing is perspective and comparison to see what is the best aspects of the wines.
I did recheck some pH values, on the 3.33 wine and the 3.83 wine. Second remeasurements agrees with the first.

I will also add that I sulfited the wines right after measuring pH. I have had a day for the Kmeta to work. Maybe I am imagining things, but does the Kmeta "freshen" the taste? I'd best describe my feeling as if the fruit and vegetal flavors are more noticable now. Or, maybe I am just tasting from a new perspective. Just wanted to mention it in case this is a real thing I am experiencing. I am enjoying the wines today more than I did 3 days ago.

I now think the 3.83 pH free run Cab is a bit sweet and is a candidate for blending with the 3.33 pH Merlot for bit of tang and the 3.33 pH green Cab, to give it the slightest hint of bell pepper. (I just mixed them in my glass, and the acid is more balanced but the individual flavors are now missing, but I am on the right track)

Thanks for the help!

 

[Snafflebit]

So... Maybe I am getting to the bottom of this issue. Remember I targeted 4.8 g/L in the must

I had a commercial Merlot wine tonight that I think has the right level of acid and I decided to test it: results are 3.56 pH and 7.8 g/L.

I then tested the TA of my wine #1 which is 3.48 pH. Results 11.25 g/L TA. Wow. What happened? I need to double check the acid additions.

@Rice_Guy I tasted the samples after I titrated them to 8.2pH. I must admit there is not much to taste after that. The samples both tasted like water with some ash mixed in. I tried to find a tannin or other flavor but it escapes my abilities.

 

[Rice_Guy]

TA of 11.25 g/L, you have a northern grape at that level. Those of us up north would put the carboy in a freezer/ fridge set at 29F/ -1C to pull out bitartrates.

For 2023 and beyond the pH is important when you are fermenting. TA does not need to be adjusted until you are doing bottling trials.

 

[wood1954]

Haha, okay it seems like all I do is field complaints on Winemaking Talk. First my wine was bitter, now it is sour. (the other wine is no long bitter BTW)

I will get some numbers posted, but what I did for 2022 vintage is backwater and acidify to a level to reach 4.8 g/L TA. Which I feel was being conservative.

I am currently running chromatography and will measure pH of the wines.

The tartness sort of hits in the back of my throat. I am a little worried it is VA, but I am not smelling vinegar or nail polish. Although the wine was under airlock, I was unable to stay on top of the SO2 since racking off gross lees. The "wine cellar" was covered by a record snowstorm and I could not get into it until April.

I know tannins will mellow with time, but will acid mellow?

Do other winemakers balance the acid by lightly backsweetening? Seems like it could work.

I have been playing with some other aging tannins also. I tried Quertanin Sweet and really like the results in another wine where it created the perception of sweetness.

I bottled a very acidic wine in 2016 and it is just now becoming drinkable so as Riceguy says the acids must combine with something to mellow out. I cold stabilized my 2022 crop and it helped a lot. Good luck in time you have some good wine.

 

[CDrew]

So... Maybe I am getting to the bottom of this issue. Remember I targeted 4.8 g/L in the must

I had a commercial Merlot wine tonight that I think has the right level of acid and I decided to test it: results are 3.56 pH and 7.8 g/L.

I then tested the TA of my wine #1 which is 3.48 pH. Results 11.25 g/L TA. Wow. What happened? I need to double check the acid additions.

@Rice_Guy I tasted the samples after I titrated them to 8.2pH. I must admit there is not much to taste after that. The samples both tasted like water with some ash mixed in. I tried to find a tannin or other flavor but it escapes my abilities.

So at least you know you aren't crazy. I would retest and confirm the TA really is 11.25. If it is, you have totally found your answer. Now you don't know for sure it's all tartaric acid as it could be acetic acid or even citric acid if you used acid blend in the additions. (edit: looked at the chromatography so it isn't citric acid, which leaves acetic acid as a possibility) Nice detective work though. I was thinking earlier that if your pH was 3.5 and your TA was 5 it should taste fine.

One thing I would not do, is blend it with hope of improvement. You risk doubling your amount of wine that is too sour! Instead, I'd wait for a hot Saturday afternoon, make a bucket of Sangria and invite your friends over.

 

[Snafflebit]

Ha, yes I think if backsweetened, this will make an excellent mixer. Sangria is a great idea, something citrusy.

I have a small chest freezer and I will try dropping out tartrate in one batch just to see the result. Some crystals were present in the racking.

I bought a fresh bottle of NaOH today to recheck the TA. But how did 4.8 g/L juice become 11.25 g/L wine. I need to figure that out.
If it is acetic acid, my hunch is the wine would be like drinking white vinegar. I either used the wrong formula to calculate the initial TA of the juice, or the TA increased over time. Is the latter possible? Maybe the NaOH is bad. guess we will find out

 

[Snafflebit]

TA of 11.25 g/L, you have a northern grape at that level. Those of us up north would put the carboy in a freezer/ fridge set at 29F/ -1C to pull out bitartrates.

For 2023 and beyond the pH is important when you are fermenting. TA does not need to be adjusted until you are doing bottling trials.

I will give "ultra cold stabilizaiton" a shot. I usually get a little tartrate fallout anyway but I can't wait another year to let time do the work.

 

[Snafflebit]

I remeasured wine #1 (3.48 pH) with new 0.1N NaOH solution and the result... 5.9 g/L TA. I hope everyone is enjoying this ride on the crazy train.

So, sodium hydroxide really does goes bad in a year. I thought it was just marketing.

5.9 g/L is still a little over what I was expecting but not much. I had a tasting of my wines with a commercial Rioja wine (coming in at 3.45 pH) and we agreed my wines are not any more sour and in fact they are a fair bit sweeter (and the merlot is a little smoky, interesting)

I swear these wines were sour a week ago, and all I can point to is that I racked and sulfited the wines since then.
I will still try the cold stabilization to see what happens.

 

[David Violante]

This is a great train…! I’m learning a lot~

 

[Snafflebit]

I started blending trials tonight on the 2021 wines.

During the process I chose one 5-gallon carboy of wine that did not wow me, but is not bad either. I decided to use this as my finishing tannin experiment. I mixed up a gram of tannin into a small amount of wine and poured it into the carboy, then it started fizzing. I noticed a little fizzing when I added the Kmeta last week but I did not think much about it.

Soooooo, maybe why I am tasting that acid tingle on my tongue is not just high acid, it is carbonation! Ugh. I would have never guessed that is the reason just from samples in my glass.

I would have never guessed that a wine sitting this long could still be releasing gas.

 

[Snafflebit]

I took a glass of my sour wine, sipped it. Yep, there is a tingle on the tip of my tongue. Then, I stirred the sample of wine with a plastic fork for a minute and tasted it again.
The tingle is gone and the wine definitely tastes like what I expect flat wine to taste like.

I made some red Pet Nat




Amazon has a prime day deal on vacuvin. Looking into that rather than whip and rack. Although a final rack might be all it takes to degas.