Fortified

Fortified wines are those made with an addition of pure alcohol (typically grape spirit) on top of that naturally produced during fermentation. The timing and extent of fortification determines the style of wine produced. In port and vins doux naturels, the alcohol addition is made to halt the fermentation process, thereby retaining natural sugar and sweetness in the wine. In Sherry, it is added after fermentation, the quantity used determining whether flor will develop or not, and therefore whether the sherry will be fino or oloroso. Fortified wines vary significantly in sweetness, and in alcohol content between 15% and 22%.