What is a Solera?

Solera is a process for aging liquids such as wine, beer, vinegar, and brandy, by fractional blending in such a way that the finished product is a mixture of ages (or vintages), with the average age gradually increasing as the process continues over many years. The purpose of this labour-intensive process is the maintenance of a reliable style and quality of the beverage over time.

Solera means "on the ground" in Spanish, and it refers to the lower level of the set of barrels or other containers used in the process; the liquid is traditionally transferred from barrel to barrel, top to bottom, the oldest mixtures being in the barrel right "on the ground", although the containers in today's process are not necessarily stacked physically in the way that this implies but merely carefully labelled. Products which are often solera aged include Sherry, Madeira, Lillet, Port wine, Marsala, Mavrodafni, Muscat, and Muscadelle wines; Balsamic, Commandaria, some Vins doux naturels, and Sherry vinegars; Brandy de Jerez; beer; rums; and whiskies.

Since the origin of this process is from the Iberian peninsula, most of the traditional terminology is in Spanish and Portuguese.