Ignacio Díaz-Maroto, M. Elena Alañón, Pablo Vila-Lameiro, Consuelo Díaz-Maroto and M. Soledad Pérez-Coello
Departamento de Ingeniería Agroforestal, Escuela Politécnica Superior, Campus Universitario s/n, Universidad de Santiago de Compostela, E-27002 Lugo, Spain
Aging wines in wooden barrels is a long-used technological step at wineries. Initially, this practice was set up for the storage and transport of wines, but later, it has been used because of its positive effects on wine organoleptic characteristics and quality. The role of wood during the aging process is crucial in several aspects. From the sensorial point of view, wood is capable of transferring aromaresponsible volatile compounds to wines. Furthermore, a reduction of astringency and changes in color are produced on aged wines as a result of the extraction of phenolic compounds from wood and the oxidation reactions produced because of the diffusion of oxygen across the wood pores.
For that, aged wines acquire distinctive sensorial characteristics that are well-appreciated by the consumer, which implies a higher price of aged wines. Although several types of woods have been used in the manufacture of barrels (chestnut, cherry, etc.), oak wood is, by far, the most common wood used in making barrels for aging purposes, not only for its chemical composition but also for both its mechanical and physical properties that facilitate the conformation of barrels.
However, the aging period carried out by means of oak barrels entails a time-consuming and expensive process. On the one hand, aged wines have to be left in the barrels during a long period before they can be brought to market because of the slow extraction process of oak wood compounds. On the other hand, it implies some problems, such as the cost and difficulty of their sanitization and handling.