Tannin fever: In vino veritas... hyperbole, too

"It feels like pashing a cat" was probably the weirdest description I've ever heard someone offer when a group of wine tasters were asked what they thought of a particular wine.
It was a big, expensive, rather famous red wine that had just been bottled, and I'd asked the group to describe how it felt in their mouth. Well, you could have heard a pin drop.
After we'd gotten over the initial awkward foot shuffling and throat clearing, we realised he was talking about that dry, rough, rasping texture of a cat's tongue when it licks your skin. Don't know the feeling? Smear a smidgen of jellimeat on the back of your hand the next time you're feeding Fluffy and you'll get the idea.
Realising nothing dodgy was afoot, our confidence was restored and someone else piped up with "it's a bit like licking an emery board I s'pose" and there was much nodding of heads and mumbling.
Then a woman at the back said, "kind of feels like you're chewing chalk" and again there was much nodding of heads and mumbles of concurrence. Now I can't say I've ever gotten intimate with my cat, licked something that I've just filed my fingernails with, or ingested chalk - but I have a fairly good imagination and can see exactly why those people chose those descriptors. I mean it's all very well to call a wine "dry", but I'd prefer to know "how dry". Being brand new, that red wine was high in acid and the tannins were really astringent, so when it was swirled around in the mouth it felt like all the moisture was being sucked out, leaving that coarse, puckering feeling.
So "cat's tongue, emery board and chalky" tannins became firmly cemented in my vinous vocabulary and I use them now without hesitation. Tannins are mostly experienced when tasting red wines and they interact with the saliva in the mouth, nullifying its lubricating action and thus the mouth feels dry. Some other words that I'd use to describe that "drying" texture in red wines would be "silky, supple, grainy, furry, powdery and puckering". Tannin and colour compounds form part of the phenolic make up of wines. Phenolics are chemical compounds that can contribute to those bitter, astringent taste sensations and they're found mostly in the skins and seeds of grapes. Phenolics also contribute to the proven health benefits of moderate daily wine consumption.
Wine contains nature's most powerful antioxidants quertican, resveratrol and epicatechin which also act as anti-carcinogens. So, if all these wonderful medicinal properties arise from the phenols present in wine, which derives them from the skins and seeds of grapes, then why don't we all just eat grapes?
It turns out the pH value and temperature conditions of the stomach aren't conducive to the extraction of the phenolic compounds from the skins and seeds of grapes. The conditions, temperatures and chemical reactions that occur between yeast, sugars, grape juice, skins, seeds and pulp all work together to produce maximum volumes of powerful antioxidants during fermentation. These factors are unique to wine.

THE FACTS
Antioxidants aside, it's the enormous impact moderate wine consumption can have on the treatment of the "vascular" and "stress-related" disorders, like coronary heart  disease that has created such a buzz. So how exactly does drinking wine help prevent heart disease?
Wine acts in five ways to prevent the blood vessels to the heart becoming blocked:

1 It lowers the bad cholesterol, so there are less fatty deposits to clog the blood vessels.
2 It raises the good cholesterol from the artery wall by taking it back to the liver to be metabolised and re-used.
3 The powerful antioxidants in wine inhibit bad cholesterol from being incorporated into the blood vessel walls.
4 Wine acts as an anti-coagulant that stops blood from clotting.
5 Because wine is able to relax you, it reduces stress.
Hooray for that, now give me a big glass of something rough and reddy right this instant!