fortified wine differs from other sweet wines in that brandy (distilled grape spirit) is added to it, which yields a much higher alcoholic content. The additional alcohol is generally used to halt the fermentation abruptly before the yeast has converted all the grape sugar into alcohol (and various fermentation byproducts). Although the history of distillation goes back further, from about 1300 c.e., brandy was plentiful enough in Europe that small amounts were frequently added to various dry wines to make them more resistant to spoilage during transport. However, it was several centuries before someone added brandy directly to a fermenting wine for the first time, probably by accident, to produce a frankly sweet wine.
