Beer of spontaneous fermentation, the Oude Reinette Étoilée Tilquin à l'Ancienne is made from the fermentation of Reinette Etoilée apples (a local belgian variety) in a blend of 1, 2 and 3 years old lambics. The final concentration of apples 390 grams per liter of lambic.

Unfiltered and unpasteurized, this beer is refermented in the bottle.