Taste right after alcoholic fermentation

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jesseb

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Hi there,

So this is my first batch from actual grape must; cabernet sauvignon. I let the grapes cold soak for a few days (actually the transport from the vineyard took 3 days) and let it ferment on the skins for two weeks. About 1.5 weeks ago I pressed the grapes and the next day racked it of the gross lees. The wine has a pH of 3.33 and a negative brix reading somewhere between -1 - 0. I've added some malocid from vinoferm according to the instructions. There are lots of tiny bubbles rising and the airlock is still quite active, so I assume the malo fermentation is happening (or just excess CO2 escaping?). It is been a week since.

If I taste the wine, it is very sour and sharp. It actually tastes more like sour grape juice than wine. I know the wine is very young and the malo conversion is probably far from complete, but what to expect at this stage? I've made wine from kits before and at this stage those wines were almost perfect already.

So my question is: How is a full-bodied red wine supposed to taste at this stage? On the scale from grape juice to wine-in-a-glass, where should it be? Does the sharp sourness mellow out a lot?

Probably my beginners impatience, I know there is still a long way to go in terms of aging/oaking but I am still curious.

Thanks!
 

Rice_Guy

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welcome to Wine Making Talk
If I taste the wine, it is very sour and sharp. It actually tastes more like sour grape juice than wine. I know the wine is very young and the malo conversion is probably far from complete, but what to expect at this stage? I've made wine from kits before and at this stage those wines were almost perfect already.
For a pH 3.3 yes it will taste sour, this is what we expect from a white grape. For a wine releasing CO2 it will have bitter carbonic acid notes. You can’t really get a good feel for finished till the carbonic acid has been removed. You have a good grape so you probably aren’t dealing with high TA like those of us growing in the mid west. ,,,Malolactic requires warmth to finish What temp are you at? If you feel it is still too acidic at racking you can chill and precipitate tartrates ,,, or again as a midwesterner I put it in the garage automatically since my TA usually is 1.0%

What else? Wine is a lesson in patience ,,, Flavor wise knowing the Titratable Acidity is a better predictor than pH. ,,, With a finished yeast fermentation we have more reliable sugar reading with gravity.
 

jesseb

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welcome to Wine Making Talk

For a pH 3.3 yes it will taste sour, this is what we expect from a white grape. For a wine releasing CO2 it will have bitter carbonic acid notes. You can’t really get a good feel for finished till the carbonic acid has been removed. You have a good grape so you probably aren’t dealing with high TA like those of us growing in the mid west. ,,,Malolactic requires warmth to finish What temp are you at? If you feel it is still too acidic at racking you can chill and precipitate tartrates ,,, or again as a midwesterner I put it in the garage automatically since my TA usually is 1.0%

What else? Wine is a lesson in patience ,,, Flavor wise knowing the Titratable Acidity is a better predictor than pH. ,,, With a finished yeast fermentation we have more reliable sugar reading with gravity.
Unfortunately I don't have the equipment to measure TA right now, perhaps in the future. The wine is sitting at room temp, about 20/21C or around 70f. After the malo I was planning to move it to the garage, where the temp will drop to about 10C/50F in feb/march. Do the tartrates have a large impact on taste/sourness?

The wine indeed had a lot of co2 when I tried it. Next time I will try to remove it before measuring/tasting...

EDIT: When talking about carbonic acid, you mean CO2 right? When I google carbonic acid, it gives me H2CO3.
 
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Rice_Guy

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TA is what your mouth feels as sour (grams of all acids), ,,, pH is what allows chemistry/ preservation to work.
 
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Do the tartrates have a large impact on taste/sourness?
Yes. All acids in the wine affect the perceived taste, including carbonic (formed from CO2, some of this late breaks down and the CO2 is emitted). With experience, you'll learn what new wines taste like and be able to somewhat judge them through the early harshness.

A common treatment for high acid wines is cold stabilization / cold crashing, where the wine is chilled for a period of time. Excess tartaric acid forms crystals and precipitates, which has the side benefit of helping the wine clear. For the most effect, chill the wine to 0C to 4C for at least a week. However, excess tartrates may drop at any temperature, and if you have excess tartaric, expect crystals at 10C.

I am not advising chilling the wine below 10C, just explaining the process. Your pH is in an acceptable range, and aging over the winter at 10C may drop crystals. If it doesn't, it likely means your wine doesn't have excess tartrates.

At this point, the wine is probably fine. I suggest you taste the wine weekly and record your impressions. This will help you in the future.
 

jesseb

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Also be aware that cold crashing a wine with a Ph of 3.3 will very likely make the Ph go down. It's not something I totally understand, but it's what happens.
Yeah this sounds a bit counter intuitive. If acid crystals drop out, the TA should go down and the pH should rise right? The relation between TA and pH is still not totally clear to me though. There isn't a direct/linear relation between TA and pH, correct?
 

jesseb

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Yes. All acids in the wine affect the perceived taste, including carbonic (formed from CO2, some of this late breaks down and the CO2 is emitted). With experience, you'll learn what new wines taste like and be able to somewhat judge them through the early harshness.

A common treatment for high acid wines is cold stabilization / cold crashing, where the wine is chilled for a period of time. Excess tartaric acid forms crystals and precipitates, which has the side benefit of helping the wine clear. For the most effect, chill the wine to 0C to 4C for at least a week. However, excess tartrates may drop at any temperature, and if you have excess tartaric, expect crystals at 10C.

I am not advising chilling the wine below 10C, just explaining the process. Your pH is in an acceptable range, and aging over the winter at 10C may drop crystals. If it doesn't, it likely means your wine doesn't have excess tartrates.

At this point, the wine is probably fine. I suggest you taste the wine weekly and record your impressions. This will help you in the future.
Thanks for the reassurance. The plan now is to let is sit warm for a few months, until the end of jan. Then I will transfer again and taste. Or should I taste more often (either to acces problems in time, or build experience by tasting)?

If, theoretically, a wine is way too sour, is it still possible to fix it by adding e.g. bicarbonate? After fermentation or even after some aging?
 
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There isn't a direct/linear relation between TA and pH, correct?
Correct. TA is a measure of the amount of acid, while pH is a measure of the free protons. While these are typically operating as expected (TA goes up, pH goes down), it's not guaranteed and should never be expected.

Thanks for the reassurance. The plan now is to let is sit warm for a few months, until the end of jan. Then I will transfer again and taste. Or should I taste more often (either to acces problems in time, or build experience by tasting)?
This is a double-edged sword. You don't want to repeatedly open the container and expose the wine, but you can't learn without doing so. During fermentation and while degassing, it's safe to take small samples for tasting, as the wine continually emits CO2. During bulk aging, if you're adding K-meta every 3 months withdraw a small sample each time. I have a long, thin wine thief that lets me pull 1/4 oz, just enough to sample.

If, theoretically, a wine is way too sour, is it still possible to fix it by adding e.g. bicarbonate? After fermentation or even after some aging?
Your wine is very young, and the taste will change dramatically over the next few months. At this point, do nothing to the acid as you have no idea how the wine will change. Time is your friend.

Later? Typically high acid is handled in 4 ways: reduce acid chemically, cold stabilize, backsweeten, and blend with a low acid wine.

If you go with a form of bicarbonate (chemical reduction), figure out how much bicarbonate you need, and use 1/4 that amount. IME the wine does not necessarily react as expected, and you can get into an acid yo-yo -- adding and reducing acid as you keep over-shooting the mark. It's far easier to add more than to take some out.

Personally, I'd go with cold stabilization first -- it has no ugly side effects. Age the wine at 10C for several months, and I'll be surprised if you don't drop at least some crystals.

Backsweetening is a second choice. I have a commercial Vignoles that is listed as "sweet". It's a very high acid wine, so the sugar and acid balance each other. I can taste sugar, but the perception is off-dry. On the homemade side, I recently bottled FWK Frutta Blackberry and Strawberry -- each wine received both conditioning (sugar) packs that came with the kits. I opened a Blackberry the other night -- even with that much sugar, it tastes off-dry.

While CS is not typically backsweetened, a small amount (1/4 to 1/2 cup sugar in 6 gallons) may reduce perceived acidity to a pleasant level.
 
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Yeah this sounds a bit counter intuitive. If acid crystals drop out, the TA should go down and the pH should rise right? The relation between TA and pH is still not totally clear to me though. There isn't a direct/linear relation between TA and pH, correct?

Here is a nice scholarly article that explains more about what happens with cold stabilization and why below Ph of about 3.6 things act differently than might be expected:

and another one:

If you don't want to backsweeten, you might also consider adding some vegetable glycerin, which helps smooth the taste and adds just a hint of something sort of sweet. This is one to be careful with, some people develop gastric issues from to much. I generally use about 1/2 to 1 oz per gallon. But let me also say you are far from doing anything to your baby wine. I wouldn't think about any of these things prior to at least 6 months aged, maybe even longer.
 

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Yeah this sounds a bit counter intuitive. If acid crystals drop out, the TA should go down and the pH should rise right? The relation between TA and pH is still not totally clear to me though. There isn't a direct/linear relation between TA and pH, correct?
The big thing to remember is that TA is first and foremost a taste related number and pH is a chemical reaction number, ,,,, and bacteria and yeast are chemical factories so they care about pH.

Your taste sensation will be linear in the range where yeast are happy but bacteria aren’t.
 

jesseb

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So a followup about the wine (and a question). I did buy a kit to measure TA and a new pH meter. The TA was about 10g/L and pH 3.22. Too much on the sour side I figured, so I added some de-acid. This was a mixture of several carbonates. I've calculated the amount needed to lower to 6g/L TA, which was about 45g. I've started adding 1/3 of that, 15g. Then I've waited 24h and measured the pH and TA again. TA was 7g/L and at pH 3.5. Good enough, so I've transferred to a new demijohn and stored it in the basement. This was two weeks ago now.

When I took a peek this morning, there was a decent layer of sediment on the bottom. It was almost white as snow, not the gray/beige color of yeast or reddish from grape particles as I've seen before. Some tartrate crystals falling out? The temp is still quite high, around 17c or 62F. Can it hurt the wine and do I need to transfer again?
 

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Sediment certainly goes through stages with time. I've noticed many times the gray becomes white, particles becoming smaller, and the boundary between the two can be quite striking. I believe you're getting fine lees and there's no rush to remove them.
 

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bitartrate solubility is temp related but I wouldn't a major decrease by dropping 3C. Intentionally removing bitartrate is frequently done at 1C or -2C.

Good technique on lowering the TA. You don't really want the pH above 3.5. note as a northern high % acid grape grower, chilling is normally done before adding a carbonate.
 

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