Cognac is brandy distilled from white wine and aged in oak barrels for at least two years. VSOP is a Cognac designation which means "very superior old pale." It certifies the Cognac has aged for at least four years.
Cognac bottles carry the labels VS, VSOP and XO to indicate how long the Cognac has aged. VS Cognac is at least two years old. VSOP Cognac is at least four years old. The XO label is reserved for Cognac that has aged for six years or longer.
The Aging Process
Cognac, as it ages, extracts substances from its oak barrel known as "dry extracts." These lend subtle flavors and darken the Cognac. Typically, the older the Cognac, the deeper the color.
Differences Between VSOP and XO
Rancio is a subtle, bitter taste, which Cognac connoisseurs prize. It takes 15 to 25 years of aging to develop. While VSOP Cognac doesn't exhibit rancio, it's more affordable than its XO counterpart. A lesser XO might cost $80, while a good VSOP can run about $40.