Olivezia's balsamic vinegar is produced from the Solera Method of vinegar making. Like in the traditional method, grapes are pressed (late harvest Trebbiano and Lambrusco grapes) and cooked. However, they are cooked in copper 'cauldrons.' This cooked mixture is placed in wooden barrels and old balsamic is added to it. This gives the mixture the necessary bacteria to begin fermenting. The barrels are only covered with a cloth so that oxygen can enter the barrels. As the mixture is left to age, it is transferred to new barrels and mixed with other balsamics of different ages. As the mixture moves through the continual process, it meets different aged vinegars and different kinds of wooden barrels (known as fractional blending). These factors give you the most unique balsamic vinegar flavors. Additionally, different producers may have their own secret recipe of fractional blending that makes their balsamic special.