After I wrote about malolactic fermentation and bottle shock in March as examples of vinogeek-speak, I heard from reader Bill Cook. He was unhappy:

“I cannot tell you how frustrating it is to read of firm tannins, smooth tannins, subtle tannins, harsh tannins (I can figure that one out, thanks), crunchy tannins (really???), supple tannins and on and on,” Cook, who lives near Haymarket, Va., wrote in an e-mail, his scorn for the craft of wine writing pulsating through his keyboard to my computer screen.

“As far as I am concerned, there are two categories — tannins that put a spike in my tongue, and those that do not put a spike in my tongue,” he wrote.

I am almost certainly guilty of inflicting some of those adjectives on tannins and readers, though I hope not the “crunchy” one.

Tannins are chemical compounds found in the skin, seeds and stems of grapes. They give red wines their structure and ability to age. We can’t smell or taste them — rather, we feel them in the wine’s texture. That’s why writers use different adjectives to describe the way tannins feel in the mouth. Supple, silky, velvety and soft describe the positive contributions tannins make to the wine. Aggressive, chewy, harsh or green tannins overpower the fruit and leave the wine astringent. Over time, tannins lengthen and precipitate out of the wine as sediment. The technical term for that is polymerization.

If someone raves about a wine’s “polymerized tannins,” just say, “My sediment exactly.”

In a big red wine, ripe tannins are evident on the finish, as though they are hiding behind the fruit, waiting for you to notice them. Such wines are said to have grip, because the tannins give a sensation of holding onto your palate. The tannins can be subtle, as in Argentina’s malbec, or very noticeable, leaving your mouth quite dry. Aggressive tannins are obvious right away; they push the fruit aside and punch you in the mouth. Or, as Bill Cook says, they put a spike in your tongue.

Vintners manage tannins throughout the winemaking process. They taste the skins and seeds and inspect the stems of ripening grapes to help them decide when to harvest. Grapes low in tannin, such as pinot noir, can be fermented “whole cluster” — with their stems — to give the wine extra heft. More-tannic grapes, such as cabernet sauvignon, syrah and nebbiolo, are usually stemmed before pressing. Letting the juice macerate on the skins for days or even weeks before allowing fermentation to begin extracts more tannin, color and flavor from the skins. Exposing the fermenting wine to small, controlled amounts of oxygen, a technique called micro-oxygenation, softens tannins and makes a young wine easier to drink.

Wine also derives tannin from oak barrels, especially new ones. After barrels are used for a few vintages, their influence on the wine’s flavor and structure becomes more subtle and less tannic. The current practice is to cut back on the use of new barrels to emphasize the wine’s fruit. (The high price of new barrels contributes to this trend.)

So far we’ve discussed only red wines. That’s because whites traditionally are made without much skin contact. Barrel-fermented chardonnay can feel tannic from its time spent in barrel. So-called orange wines — whites fermented on their skins like red wines — can be surprisingly tannic.

As consumers, we should remember three basic words: Fat cuts tannin. Big red wine calls for big red meat. That’s one reason cabernet sauvignon dominates most steakhouse wine lists.

What about those “crunchy” tannins? I imagine the writer was trying to convey the texture of a young red wine with lots of tannin — a wine that you can’t just swish around your mouth but almost have to chew into submission. Whether that was considered a positive attribute is hard to say.

Does wine lingo trip you up? Write to Dave McIntyre at food@ McIntyre blogs at On Twitter: @dmwine.