From the brewery:

Duchesse de Bourgogne from Brouwerij Verhaeghe is the traditional Flemish red ale. This refreshing ale is matured in oak casks; smooth with a rich texture and interplay of passion fruit, and chocolate, and a long, dry and acidic finish. After the first and secondary fermentation, the beer goes for maturation into the oak barrels for 18 months. The final product is a blend of younger 8 months old beer with 18 months old beer. The average age of the Duchesse de Bourgogne before being bottled is 12 months.