The use of oak has been prevalent in winemaking for at least two millennia, first coming into widespread use during the Roman Empire. In time, winemakers discovered that beyond just storage convenience that wine kept in oak barrels took on properties that improved the wine by making it softer, and in some cases, better tasting. Robert Mondavi is credited with expanding the knowledge of winemakers in the United States about the different types of oak and barrel styles through his experimentation in the 1960s and 1970s.
How much wine evaporates from an oak barrel in one year?
The porous nature of an oak barrel allows some levels of evaporation and oxygenation to occur in wine, but typically not at levels that would cause spoilage. In a year, the typical 60-gallon barrel can lose anywhere from 5 1/2 to 6 1/2 gallons of wine through evaporation. This is actually a good thing, allowing the wine to further concentrate its flavor and aroma compounds.