What caused the difference in alcohol by volume of wine?

If you're a regular wine drinker, you will notice that different varieties of wine have different alcohol by volumes: whether it is red wine or white wine or champagne. And even if it's all about red wine, their alcohol by volume is different. So what accounts for the difference in alcohol by volume?

What are the effects of alcohol by volume on wine?

For wine, the most direct effect of alcohol by volume is the "body" of the wine, which refers to the "richness" or "thickness" of the wine produced in the mouth. The more alcoholic the wine, the thicker the body, this is because alcohol can give the wine a "sticky" state. You can imagine the difference between lemon juice and whole milk in the mouth. Alcoholic wines will give your mouth more feeling of “thickness”, not as light as lemon juice.

What are the factors that affect alcohol by volume of the wine?

1. Winemaker

Each winemaker, when deciding when to pick grapes, picks the grapes when they reach a certain sugar and flavor concentration, according to the winemaking methods and consistent styles of the winery. This is the first step in determining the alcohol by volume of a wine.

2. Climate of the year

In general, in the warm and hot climate producing areas, the photosynthesis of the grapes is strong, resulting in high sugar accumulation in the fruit and high alcohol content during the fermentation process. In contrast, in the cold and cold climate producing areas, the grapes have a lower sugar content, so that the resulting wine has a lower alcohol by volume and a lighter taste.

3. Taxation

According to American wine law, for wines with less than 14 percent alcohol by volume, a 1.5% error is allowed; while for wines with more than 14 percent alcohol by volume, the maximum error can be up to 1%.

In 2015, the Journal of Wine Economics published a research report that analyzed the alcohol by volume labels on 100,000 wines. This research found that New World Wine was labeled 0.45 percent less alcoholic than they actually were, and the Old World Wine was labeled 0.39 percent less alcoholic than they actually were.

One reason for this is the tax. Under U.S. wine law, alcohol over 14 percent is taxed more than alcohol under 14 percent. As a result, wineries that should have labeled 14.5 percent alcohol by volume will have to label 14 percent to avoid paying taxes.

4. The comprehensive factors

Climate, grape varieties, soil conditions and other factors in different countries and regions will lead to the sugar content of grapes, which will lead to the difference in alcohol by volume of wine. Both too high and too low alcohol by volume will affect the taste of the wine: too high will mask the natural aroma of the wine, too low will lead to insufficient wine taste.

In order to change the alcohol by volume of the wine to meet the market demand, various techniques are applied to the wine production process. For example, if the sugar content of the grape is too high, the Spinning Cone Column (SCC) can be used to reduce the alcohol content of the wine.

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References

Breaking Down the Booze: Wine Alcohol Levels Explored. (n.d.). Retrieved from https://www.whichwinery.com/ask-the-somm/breaking-down-booze-wine-alcohol-levels-explored/.

Halleck, R. (2019). Wine Alcohol Content: Important Facts to Know. Retrieved from https://www.wine.net/wine-alcohol-content-important-facts-know/.

Wine: From the Lightest to the Strongest. (2019). Retrieved from https://winefolly.com/tutorial/the-lightest-to-the-strongest-wine/.