acidity vs tannins

In preparation for the wine tasting I hosted last week I was online looking at various wine tasting cards. One of them had separate catagories for tannins (reds) and acidity (whites).

Don't red wines have noticable acidity?

Good question. They sure do, but I for one have trouble differentiating acid and fine tannins in red wines. I even bought a pH meter, but I don't think I ever got it calibrated correctly. If I ever tasted wine with experts that would be the first differentiation that I would explore.

I await responses with you.

Covert

All wine has acidity, some more than others. Usually, whites deliver higher acidity than reds. All reds are put through a secondary fermentation known as malolactic, which literally reduces natural wine malic acid to lactic acid, thereby softening the wine's acidity. Not many whites get that kind of tratment--the most common white that does is Chardonnay.

As for tannin, that is delivered from the skins, stems and seeds. Reds are fermented before the grapes are pressed, so reds deliver more tannin than whites, which are mainly pressed first and then fermented without skins.

Also, oak barrels impart tannins of a separate sort than the natural grape tannins, but tannins nonetheless.

Tannin is a compound made up of tannic acids, but when referring to wine's acidity most people are talking about tartaric, malic and citric acids.

Good question. They sure do, but I for one have trouble differentiating acid and fine tannins in red wines. I even bought a pH meter, but I don't think I ever got it calibrated correctly. If I ever tasted wine with experts that would be the first differentiation that I would explore.

I await responses with you.

Covert

Covert,

Tannins and the other acids work differently on the palate.

If strong enough, tannin will coat the tongue, cotton mouth style. At the finish it comes off as astringent--bitter.

Tartaric and the other acids usually register at the sides of the tongue, sometimes they can even curl the tongue at its sides. They also remind of acidic fruits like lemons, lime, apple, etc.

Not to belabor a point, but these are the things that "dry" the palate, which makes it possible for a so-called "dry" wine to sometimes contain more sugar than you might imagine.

Thomas,

Robert Parker frequently mentions the degree of acid in red wine without defining the type of acid. He apparently thinks it is worth perceiving and noting. Does he note it only with regard to how the wine might age, or is there a pleasure or discrimination factor involved?

Covert

The answer to that, Covert, will have to come from Robert Parker.

All the acids help wine in the aging process, but in red wine the tannins likely play a larger role in aging, mainly because of the lowered acidity of reds. And since whites usually do not age as well or as long as reds, it is likely because they aren't well stocked with tannin.

I say "likely" because I am old enough to have learned that for every generality there is always an exception, which is partly why I abhor one phrase solutions and answers.

Tartaric and the other acids usually register at the sides of the tongue, sometimes they can even curl the tongue at its sides. They also remind of acidic fruits like lemons, lime, apple, etc.

I can tell if a red wine is tannic, but it seems to me that acidic variations in red wines are more subtle than in the case of whites, and even years that are supposed to be relatively high in acid never come close to curling my tongue. For the sake of discussion, how would an average '94 Bordeaux differ perceptually from a low acid '97 if both wines had the same kinds and degrees of tannins?

Covert

Covert,

Mainly, because red wine acidity is purposely lowered by way of malolactic fermentation, it is difficult to determine the relative strength or weakness of the acid. It could be that those who talk of the acidity of reds are refrring to tannin.

But for an indication of how a red wine with high acidity can taste, try Barbera--an Italian one. I had one last night and the acidity did nearly curl my tongue at the sides. It was great with the ravioli and fresh, sweet tomato sauce, made sweet by an addition of Marsala. It was a good night.

One of the reasons many Italian red wines are considered "food" wines is that many of them (Barbera comes to mind) balance sugars with acids rather than with tannins, and acids make your mouth water, which makes you crave food!

A wine will be more overtly acidic if it has not been through malolactic fermentation, where malic acids are converted to softer lactic acids. That's why, for example, Chablis is usually tarter and livelier than a barrel-aged Montrachet. In the former, malolactic fermentation is suppressed, in the latter, it is most often encouraged. The tradeoff is freshness and liveliness in the Chablis, as opposed to richness and complexity in the Montrachet. I am, of course, grossly oversimplifying, but that's the general gist.

But for an indication of how a red wine with high acidity can taste, try Barbera--an Italian one.

Thomas,

Now that you mention it, I did have an Italian red where I commented that it was really acidic. I had forgotten, but now I can kind of remember the experience. Thanks. That actually answers my question.

Covert

One of the reasons many Italian red wines are considered "food" wines is that many of them (Barbera comes to mind) balance sugars with acids rather than with tannins, and acids make your mouth water, which makes you crave food!

Dave,

I am not sure what you mean by 'balance sugars with acids', given that any decent or better Italian red wine will be dry.

Barbera also has almost no grape tannins, so if you get an unoaked one it's a demonstration of acid without tannin. (Barbera d'Asti is particularly distinctive in this regard.) On the other hand enough acidity can start to taste astringent, mimicking tannins...curiouser and curiouser...

But for an indication of how a red wine with high acidity can taste, try Barbera--an Italian one.

Thomas,

Now that you mention it, I did have an Italian red where I commented that it was really acidic. I had forgotten, but now I can kind of remember the experience. Thanks. That actually answers my question.

Covert

Glad to help. Just be careful with generalizations about Italian wines--not all of them are acidic. Some can be quite tannic, like Aglianico and other more southern wines--if you consider Sicily as part of Italy, which a lot of Sicilians and Italians don't, Nero D'avalo or other Sicilian reds can be quite tannic.

And many Cabernet-infused Italian wines can also be tannic.

There are four basic tastes; sweet, sour, bitter, and salty. Tannin is just about the only thing that makes wine bitter. Acid and other things make it sour, and fruit and other things make it sweet. It all adds up to balance; hopefully.

There are many acidic reds. In addition to Barbera, there is Sangiovese, and Pinot Noir just to name a few.

If you taste salt in wine, you have a big problem.

Tannins have a 'drying' effect on the teeth and gums.

If your mouth 'waters', that indicates acidity, which is detected on the sides and rear of the tongue. Wines lacking in acid will feel flabby. Great sweet wines, like Sauternes or Tokaji Aszu, will have more acidity than you think because they have such high levels of sugar. Without the acid, they would be cloying and syrupy.

This is what we were taught in WSET class.

A wine will be more overtly acidic if it has not been through malolactic fermentation, where malic acids are converted to softer lactic acids. That's why, for example, Chablis is usually tarter and livelier than a barrel-aged Montrachet. In the former, malolactic fermentation is suppressed, in the latter, it is most often encouraged.

That's entirely false. It's true that wines that have been through ML are softer, but that's not why Chablis is different than wines from Montrachet or anywhere in the Cote de Beaune. Chablis almost as a 100% rule goes through malo too. Chablis is tarter and livelier because it has more acidity before or after fermentation and/or it's fruit profile is less pronounced because the grapes ripen differently because of the colder climate and/or the alcohol is lower because of the climate. A handful of Chablis producers do at times partially block ML but it is far from a defining charcateristic of the wine region. The easiest way to tell this is to taste any of the thousands of Chablis that do go through ML, and see that the wines are as "typical" as the others. If a producer of Chablis halts ML, when you are tasting with them they will indicate so, as it is an exception rather than the rule. (An example of this being William Fevre in 2003; they used partial ML in this instance - maybe not for every wine but for some I forget - because the historic heat wave made wines that required a unique approach.)

That ties in with Oliver's question: I am not sure what you mean by 'balance sugars with acids', given that any decent or better Italian red wine will be dry.

Alcohol has an apparent sweetness. It's a chapter in Peynaud that I've often paraphrased here. Balance in wine is acheived through equilibrium of alcohol & sugar and tannin & acidity. So a wine with a lot of alcohol can balance it's aidity with it's sweetness. Peynaud suggests following experiment: Remove the alcohol from wine by heating it. Replace the same volume of alcohol with water. The result will be a completely imbalanced undrinkable wine - overly acidic or overly tannic or both.

If you taste salt in wine, you have a big problem.

Unless you're drinking Muscadet!

There has been a lot of good info posted here so far. The acid in wine can be measured by Total Acidity (TA) or pH. Quite simply, generally, whites have higher acidity (lower pH) than reds. The Total Acidity (TA) of dry whites generally ranges from 0.70 to 0.85, and higher if off-dry or sweet. Residual sugar balances high acid levels. For dry reds, it ranges from 0.60 to 0.75. Acid = sour (think lemon juice in water). Tannin = astringency (think unsweetened black iced tea). AFAIK, there is no simple test for the quantity or type of tannins. The amount of tannins varies with the grape variety, the amount of skin contact and the manner and time in which it's aged (oak vs no-oak). Generally, the predominanat acids found in wine are tartaric, malic and lactic, with perhaps traces of citric and/or acetic. Each of these present a different mouthfeel. There are probably an infinite variety of tannins, which can change over time, and each can also present a different mouthfeel.

The thing I sometimes notice is the tip of the tongue sensation? I am OK with the gum/roof of the mouth feeling(!!) but the tongue? Is this the effect of higher acidity level? I once read somewhere it was something to do with salt?!!!

Edit I have just looked at Jamies book and he goes into a lot of info obviously, Ch 20, he talks about flavour and its perception. Will give it a good read later on.

Hope we didn't scare Ronica away!!!!

Salute

The thing I sometimes notice is the tip of the tongue sensation? I am OK with the gum/roof of the mouth feeling(!!) but the tongue? Is this the effect of higher acidity level? I once read somewhere it was something to do with salt?!!!

Edit I have just looked at Jamies book and he goes into a lot of info obviously, Ch 20, he talks about flavour and its perception. Will give it a good read later on.

Bob,

Check out Jamie's chapter on reduction. It harkened me back to a thread we had going about critics and mercaptan. Every so-called wine critic should read that chapter alone, and then try to figure out whether or not a little technical training is a good idea.

Thanks Thomas, will do after I have finished all the outside chores around here!! As an aside, I really like the book but do not have a scientific mind to take it all in at once. Read bits here..there..as I feel.

Bob,

I've got winemaking training and some grape growing experience, but that is the extent of my scientific knowledge. I find that Jamie did a good job at making the material--as we say these days--user friendly; then again, I already have a base in a lot of the stuff he covers so maybe I should find it easier to follow him.

Bob - I have just looked at Jamies book...

What book? Do you have a link?

If you taste salt in wine, you have a big problem.

Unless you're drinking Muscadet!

Or manzinilla!