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, with the average age gradually increasing as the process continues over many years. Solera means literally "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 transferred from barrel to barrel, top to bottom, the oldest mixtures being in the barrel right "on the ground". Products which are often solera aged include Sherry, Madeira, Lillet, Port wine, Marsala, Mavrodafni, Muscat, and Muscadelle wines; Balsamic, Commandaria, and Sherry vinegars; Spanish brandy; beer; rums; and whiskies.