What is "quadrupel"

A quadrupel is beer intended to be stronger than a tripel, so the alcohol by volume is 10% or more. Beyond that, there is little agreement on the status of Quadrupel as a style. Beer writer Tim Webb notes that similar beers are also called Grand Cru in Belgium.

Quadrupel is the brand name of a strong seasonal beer La Trappe Quadrupel brewed by De Koningshoeven Brewery in the Netherlands, one of the five Trappist brewing abbeys not in Belgium (the others are the Engelszell Abbey in Austria, St. Joseph's Abbey in the United States, Tre Fontane Abbey in Italy, and Zundert from Maria Toevlucht Abbey in the Netherlands).

In other countries, particularly the United States, quadrupel or quad has become a generic trademark. The term may refer to an especially strong style of dark ale, with a characteristic spicy, ripe fruit flavor.