Port's sweetness comes from the fortification process that captures residual sugars absent in other wines.
Port is a sweet, fortified red wine that comes from Portugal's Duoro region. It is often served as a dessert wine, though some varieties are drier than others. Port is unlike other red wines because of the fortification process, which alters its flavor and alcohol content. Port is sometimes confused with spirits like brandy, but it is, in fact, a sweet red wine.
Winemaking Process
The process for making port is unlike the typical winemaking process. Once a red wine is made from grapes, it is fortified with aguardente, a neutral grape spirit that stops fermentation, the natural process by which fruits break down to become alcohol. When fermentation stops, port is left with residual sugar and high alcohol content. The alcohol content in port is 19 percent to 22 percent by volume. Most red wines contain only 11 percent to 14 percent alcohol by volume.
Sweetness of Port
Port is generally considered a dessert wine, but different varieties vary in sweetness. The level of sweetness is determined by the winemaker, depending on when he interrupts fermentation with the addition of aguardente. There are five recognized degrees of port sweetness: very sweet, sweet, semi-dry, dry and extra dry. Very sweet port contains more than 130 grams of sugar per liter. Sweet port contains 90 to 130 grams, semi-dry contains 65 to 90 grams, dry contains 40 to 65 grams and extra dry contains only 40 grams or less of sugar per liter.
Types of Port
The four types of port wine are distinguished by techniques used and length of aging. Ruby-style ports are young ports with a deep red color and strong fruity aroma, aged in the bottle. Tawny ports are aged in wooden casks over a long period of time. The aging process and exposure to oxidation gives them a golden color, resembling brandy, and the flavor of dried fruits with notes of wood. White ports are bottle-aged, and run the range of sweetness. As they age, their color becomes hard to discern from ruby port. Rose is pink due to limited exposure to the grape skins. It is bottle-aged, best consumed young and has distinct fruity notes.
Comparing Port to Other Wines
Port is, by far, the sweetest red wine available. The residual sugars it contains are absent in unfortified wines. Some varieties of red wine are sweeter than others. Red Zinfandel and Pinot Noir are rather sweet and fruity. Madeira is a fortified wine similar to port. Ice wine is very sweet, made from grapes frozen on the vine. Other dessert wines include Banyuls, Moscato and Sauternes.
Tags: alcohol content, contains grams, comes from, dessert wine, fortification process, fortified wine