A fortified wine is a wine that has a higher content of alcohol, or alcohol by volume content (ABV), achieved through the addition of a distilled spirit at some point during the vinification process. As with regular wine, there are numerous styles of fortified wines made throughout the world (though most originate from Europe), with winemaking methods, laws and traditions varying from region to region.

Fortification of Wine

Fortification is the process of adding a distilled spirit to fortify, or increase the alcohol content, of a wine. The practice dates back hundreds of years, initially used as a means of stabilizing wines and reducing the risk of spoilage or oxidation. In the higher alcohol, "fortified" environment, yeasts and bacteria that may normally be harmful to wine are unable to thrive.

With the introduction of fortification came the possibility of reliable long-term aging of wine, as well as long distance transportation, something that was vital at a time where European nations boasted vast colonies spanning the globe. Fortification of wines allowed wines to survive a long journey to the Caribbean or African coast; Madeira, for example was born on the decks of seafaring ships where the Caribbean sun baked the barrels' contents, creating the modern Madeira we know today.

Spirits Used to Make Fortified Wine

For all of the major fortified styles of wine, law dictates that the alcohol used in fortification must be a distilled grape spirit. This spirit can be something very simple like an aguardente vinica or something more complex like a brandy, depending on the desired style of fortified wine. Generally speaking, however, the spirit is added for its alcohol content alone and for that reason clear, flavorless grape spirits are preferred.

When is Spirit Added During the Winemaking Process?

The time at which fortification occurs during winemaking can have a profound effect on the style of a fortified wine. In the production of dry fortified wines, such as Sherry, fortification doesn’t occur until after alcoholic fermentation has ended, thus, ensuring that there is no residual sugar to add sweetness to the wine.

In the production of sweet fortified wines, such as Port, fortification occurs while alcoholic fermentation is still taking place. The addition of a distilled grape spirit kills yeast present in the wine, prematurely halting alcoholic fermentation and leaving residual sugar. This results in a sweet fortified wine.

Styles of Fortified Wine

Besides sweetness, there are a number of other variables that can affect the style of a fortified wine, including the grape varieties used, the type of base wine, the method and overall time of aging technique used, climatic conditions of the winemaking region and the liquor used for fortification. (Read on in "Fortified Wines: The Difference Between Marsala, Port & Sherry")

The guidelines, traditions and laws vary between different fortified winemaking regions and have resulted in a number different style of fortified wines, the most notable of which are:

Sherry

Sherry, also known as Jerez in Spanish or Xérès in French, is a fortified wine made in the Andalucia region in the south of Spain.

Aging plays an important role in the production of Sherry, and the numerous methods and resulting styles can be very confusing. Broadly speaking, there are two main styles of Sherry: those that have been aged biologically (e.g. Fino, Manzanilla, aged under a protective layer of yeast to prevent oxidation) and oxidatively (e.g. Oloroso, aged in direct contact with air without the protection of yeast). Biologically aged Sherries tend to be lighter and clearer than their oxidatively aged counterparts, which are dark and heavy, with more complex characteristics.

Most Sherries are made using the Palomino Fino grape variety and are fermented dry before fortification. There are a few sweet styles out there, however, the most famous of which is the luscious, syrupy Pedro Ximenez, made from the grape variety of the same name.

Sherry pairs remarkably well with food, especially the lighter, drier, biologically aged styles, which are the perfect accompaniment to traditional Spanish tapas dishes of the same region. On a hot day, a chilled Fino works as an aperitif, while a Pedro Ximenez should be reserved for after dinner.

Port

Port is a sweet fortified wine, made from grapes grown in the Duoro region of Portugal. Historically, the wine enjoyed great success in England, its higher alcohol content and sweeter nature making it a perfect match for the English palate.

While we tend to think of Port as a fortified red wine, rosé and white styles are also produced, albeit in much smaller quantities. Of the many grape varieties allowed in the production of Port, the most commonly used are: Touriga Nacional, Touriga Franca, Tinta Barroca, Tinta Roriz (Tempranillo), Tinta Cão, and Tinta Amarela.

The sweet flavor of Port is achieved by stopping alcoholic fermentation using aguardente, leaving residual sugar in the wine. Like Sherry, it can be classified into different styles including those that are fruity and intended to be drunk young (Ruby and Reserve Port), those that have been aged (Tawny and Aged Tawny), and those made from stand-out vintages which benefit from further bottle aging (Vintage).

The heavier, sweet nature of Port mean that it is commonly paired alongside cheese or consumed as a post-meal digestif.

Madeira

Madeira is a fortified wine native to the Portuguese islands of the same name. The wine is made in a variety of styles from dry to sweet and its unique flavor comes from sustained exposure to heat during the aging part of the winemaking process.

These effects were first discovered during the age of sea exploration, when unsold wine that was to be traded returned to the islands, where winemakers realized that the wine’s flavor profile had changed dramatically.

Nowadays, Madeira is heated under much more sophisticated, controllable conditions in the winery and wines also undergo some oxidization and mild pasteurization.

Dry Madeira can be consumed alone as an aperitif, while sweeter styles are much better paired with desserts. (Learn more in "How To Pair Wine With Dessert")

Marsala

Marsala is named after the city in which it is produced on the Italian island of Sicily. This fortified wine can be made in a range of styles from dry to sweet, using white or black grape varieties. The white grape varieties commonly used to produce Marsala are Grillo, Inzolia, and Catarratto while black varieties used are Perricone, Calabrese, Nero d'Avola and Nerello Mascalese.

Marsala wines are classified into a variety of different styles, depending on sweetness, color of grapes used and duration of aging. In Sicily, the wine is typically served as an aperitif, with dry versions also a popular pairing alongside cheese, fruits or pastries.

Fortified wines are usually served before dinner or after, they are strong, sometimes sweet, but always hot. Try your hand at one today.