Tierra Vieja, The quality and complexity of Vinagres de Yema is a result of the dedication to the time honored tradition of the solera-criadera method of aging. The process begins with the harvest of Palomino grapes grown near Jerez, Spain, and a series of barrels called criaderas. Each criadera contains vinegars with similar flavor characteristics, but that have been aged for different lengths of time. When the solera, the barrel with the oldest vinegar, is tapped for bottling, it is never fully drained. Instead, the remaining vinegar is then blended with vinegar from the next younger criadera, and so on through the series of bottles until the youngest is topped off with fermented must.