It is surprising how long it has actually taken me to write something about Orval. It's a beer readily available but one I never think to get, as a result I only tried it for the first time a couple of weeks ago. Orval is one of those beers I like to think of as a comparison beer. People will often use it when describing another beer citing that it is a little like orval or maybe even orval-esque. The reason for this is that Orval uses a yeast called Brettanomyces in it's bottling stage. The result is pretty dramatic.
Brett creates a sourness in beer, usually this would be seen as an infection and the beer would be classified as spoiled but for the adventurous, a good sour beer can be a wonderful thing.
Bottle conditioning your beer with Brett also has the effect of giving you different characteristics depending on the age of the beer. All bottle conditioned ales of a higher ABV will usually mature and age for years with the character of the beer changing with time but doing so with Brett is said to be very interesting.
My bottle was only about 7 months old but the sourness was there, if only in the background.
As a beer on its own this is a wonderfully well made Belgian Trappist ale. It explodes in to the glass with a massive foamy head. With the first sniff you know its a Belgian beer. It is peppery, yeasty, fruity (fruit cake) and citrusy (lemons & oranges). Once in the mouth you experience reason for the explosion of head during pouring. This is a very carbonated beer and no doubt the brett has something to do with that. One downside I thought was the it was a little bit on the thin side but I don't think it detracted from the overall experience.
I am very curious to try some Orval that has been sitting around for a few years.