Alcohol content in wine can range from low alcohol wines that contain about 5.5% ABV (alcohol by volume) from high alcohol wines that can reach up to 23% ABV. Many factors can affect the alcohol content of wine but what contributes the most to the alcohol content in wine are the grapes. As grapes grow they develop more and more sugar content. The grapes sugar is later converted into alcohol in the winemaking process. Considering that, grapes that grow on colder climate regions tend to have less sugar and make less alcoholic wines while those which grow in the warmer climate make stronger high alcohol content wines.
Very High Alcohol Content Wines
The high alcohol content wines can be made in two ways- either by fortifying it or making it naturally. It is rare to find high alcohol content wine made in a natural way which means that some of the strongest wines are fortified. Fortified wine is made with the addition of distilled grape brandy in order to increase the alcohol content of wine.
As said before, some of the strongest wines come from the warm regions like Portugal, Spain or Italy. Fortified white wines such as Portuguese Madeira or Spanish sherry can have really high ABV. Red wines like Portuguese Port or Italian Amarone can end up with percentages as high as 20%, so sip slowly.