Question regarding tannins and acidity

I have been taught that:

Cooler climates tend to produce wines with higher acidity, lighter body, less alcohol and less tannin.

Hotter climates tend to produce wines with less acidity, fuller body, higher alcohol and more tannin.

Leading me to believe, perhaps incorrectly, that somehow tannins and acidity are inversely correlated?

How then do you end up with a wine in which the tannins and acidity are well balanced?

Leading me to believe, perhaps incorrectly, that somehow tannins and acidity are inversely correlated?

You are correct. They are not inversely correlated.

There are a number of other key variables missing from your analysis, most notably grape type (i.e. tannic potential of specific grapes) and winemaking techniques.

How then do you end up with a wine in which the tannins and acidity are well balanced?

That's what everyone tries to figure out each year they make more wine!

Right. Acidity and sugar do show an inverse correlation, though, because the ripening process converts acids to sugars. In a cooler climate you might not get full ripening, leaving more acid.

Tannins are mostly in grape skins, stems and seeds. Longer fermentation on the skins will extract more tannin, as will partial destemming (as opposed to full destemming). And tannins also develop as the grapes ripen, so you might find more tannins in the hot-climate grapes. This is independent of the acid-to-sugar development. Tannins in the finished wine can be controlled through shorter skin-contact during fermentation, and by using fining techniques on the finished wine.

And tannins also develop as the grapes ripen, so you might find more tannins in the hot-climate grapes.

Maybe. I kind of suspected the opposite, but to be honest I don't really know.

What I AM sure of is that tannins in unripe grapes are harsher. When grapes reach phenolic maturity the texture of the tannins becomes more fine-grained. I also find that ripe fruit flavours tend to mask tannins, making any astringency less obtrusive.

Right. Acidity and sugar do show an inverse correlation, though

..except in ice wine..

Just think about this. The vine itself with the help of nature can perform this balancing act (for if it wasn’t capable of doing this it wouldn’t survive). During the early stages of a grape berry’s development the main goal is to produce a viable seed and keep the animals and birds from foraging the young developing fruit. So very likely substances like tannins and acids (especially tartaric acid) are very dominate during the early stages of a berry’s development (a defensive mechanism to keep animals and birds away). Once a viable seed is developed and as the berry ripens, softens, increases in size and sugar concentration increases it becomes and more pleasant to eat. The substances within the berry become more and more “balanced”. (Does the tannin structure chemically get altered as the berry ripens or just gets diluted? -I’m not sure).
When it comes to tannin in wines things get a little more complicated. As Ernie from Berkley has suggested winemaking techniques have a lot to do with it. Storing wines in oak barrels (especially new ones) may introduce more tannin compounds to the wine. Properly aging and storing wines also play a role in the tannin profile of a wine. Remember the tannin profile of a wine can range from harsh green tannins to lush ripe cocoa tannins.

Salute

Right. Acidity and sugar do show an inverse correlation, though

..except in ice wine..

Ice wine is an exception. Ice wine is a case of natural cryoextraction--removal of water from the grape juice by freezing it out as ice crystals. Botrytis infection is another exceptional case--the fungus causes loss of water without the usual consequent loss of acidity.

-Paul W.

......Acidity and sugar do show an inverse correlation, though, because the ripening process converts acids to sugars. In a cooler climate you might not get full ripening, leaving more acid....

If I'm not mistaken, and to be a bit more specific, the level of sugar is inversely proportional to the level of malic acid, while the level of tartaric remains constant.