Oud Beersel Oude Lambiek is the base oude lambiek for Oud Beersel’s blends. It is brewed at Brouwerij Boon and barreled at Oud Beersel. It is a principal component in the blend of Oud Beersel Oude Geuze Vieille and is also released in 5 liter containers. It is labeled as 5% ABV. The exact time when a lambic switches from jeune to vieux is based on the fermentation progress and is at the brewer’s or blender’s discretion.