Wine terms: High alcohol

This is one of the most controversial and divisive issues in the wine business today. In fact, there isn ?t even any agreement about what defines high alcohol ? those who make this style of wine, as well as those who drink them, consider them to be normal.

But there is a starting point. Generally, white wines with an alcohol level higher than 14 percent and red wines higher than 14.5 percent are considered high alcohol. In this, they are each 1 to 1 1/2 points more than what was considered high alcohol 10 to 20 years ago.

The question of whether these levels are too high to produce quality wine is something for another day (though the Wine Curmudgeon ?s preference for traditional alcohol levels are well known). It ?s enough in this post to discuss what ?s going on, which comes after the jump:

Some technical stuff first: Alcohol is measured by percentages of volume, so that a wine with 14 percent alcohol is 86 percent something else (mostly water). The alcohol level in most beer is 4 or 5 percent, while it ?s 40 to 45 percent in spirits. You can compare levels across beverages using something called drink equivalence, which says that one 4- to 5-ounce serving of 10 to 12 percent wine has about the same amount of alcohol as a 12-ounce beer, which has about the same amount of alcohol a 1 1/4-ounce shot of whiskey.

The other technical bit? It ?s called fermentation, the process by which yeast converts the natural sugar found in wine grapes to alcohol. The more sugar in the grapes, the more alcohol is possible in the wine.

These days, that drink equivalence example is becoming increasingly less relevant, since fewer and fewer wines are made at the 10-12 percent level. It ?s not unusual to find 14.5 percent chardonnays, 15 percent cabernet sauvignons, and 16 percent zinfandels and shirazes. When I started writing about wine in the late 1980s, most cabernets were less than 14 percent, and it was rare to find a white wine higher than 13 percent.

So why are more wines more alcoholic?

? Better farming techniques. Grape growers, especially in California, produce healthier vines. Healthier vines mean riper fruit, which means more sugar, which means more alcohol.

? More efficient yeasts that do a better job of converting sugar to alcohol.

? Robert Parker and the Wine Magazines. They like high alcohol wines (and Parker really does), so winemakers who want to get high scores make high alcohol wines.

? Global warming, or at least consistently warmer temperatures in the world ?s major wine growing regions. That means riper fruit, which means more sugar, which means more alcohol.

? Because they can. Winemakers have egos, and if one of them makes a 15 percent wine, another is going to make a 15 1/2 percent wine, and then another is going to make a 16 percent wine.

For more on high alcohol: