Welcome to the last article in our wine structure series. I hope you’ve enjoyed it so far and learned a thing or two about the different factors that make up your glass of wine.  If you missed the articles on acidity and tannin, and sugar, make sure to check those out, too. Today we’re discussing alcohol, which is arguably the most important factor in determining a wine’s body.

Alcohol develops when yeast converts sugar into ethanol during fermentation. The more sugar there is in a wine, the more alcohol will be produced if a wine is fermented to dryness, meaning the yeast eat all of the sugar. If fermentation stops before all of the sugar is gone, the wine will be sweet. Fermentation can be stopped by the winemaker if they want a lower alcohol, sweeter wine, or it can stop naturally if there is just too much sugar for the yeast to consume. Most non-fortified wines range from 11%-14% alcohol by volume.

Alcohol has affects your glass of wine in a few ways. First, it increases your perception of the wine’s body. Higher alcohol levels equal fuller body, meaning the wine will feel heavier when you drink it. Some wines with low alcohol levels can seem thin or watery unless they have a lot of sugar or tannins to make up for the alcohol level.

Alcohol can also cause a hot or burning sensation, particularly when you either spit or swallow the wine. It can also cause something called nasal burn, which is exactly what it sounds like- you get a burning sensation in your nose when you sniff alcohol. It also makes it harder to detect the aromas and flavors of the wine. These sensations tend to be tempered by chilling a wine.

Unlike tannin, alcohol levels do not decrease as a wine ages. The ABV of a wine bottled 20 years ago will be the same as it was the day it was bottled.

If you’ve read through the series, you should be able to confidently discuss the different structural components of a wine and impress all of your friends at parties. Our next series on grape varietals will start soon, so stay tuned for that!