Chimay is the most well-known of the Trappist breweries, and most people who are beer fans will have had a glass--it's available at many grocery stores and you even see it on tap sometimes. One shouldn't construe this availability as evidence that it's a mass-market beer, though; Chimay is one of the most highly regarded brands in the world.
Compared to some of the other European monasteries, Chimay is but a spring chicken. The abbey at Scourmont (Chimay town) wasn't founded until 1850 very near the French border. They were early brewers, however, and started in 1862. One of the quirks of location is the groundwater of Chimay, which is very clear and free of minerals--producing the soft fullness for which the beer is famous. According to Jackson, the brewery needed to be brought back into production after WWII, and the monks brought in Jean De Clerck, who introduced the yeast strain still in use and formulated the basic versions of the three beers Chimay still brews.
Chimay produces three styles of beer, "White" (a tripel), "Red" or Première (a dubbel), and "Blue" or Grande Réserve, a style unique to Chimay. The brewery uses about 10-15% wheat malt in each of its beers as well as dextrose--not the candi sugar characteristic of Belgian ales. Until the 1990s, the brewery used open fermentation. When they switched to tall, conico-cylindrical fermenters, the beers apparently lost complexity ("grievously," according to Jackson).
The recipes were developed in collaboration between the master brewer, Father Théodore, and Jean De Clerck in the two decades following WWII, and the final beer to join the line-up was White, in 1966. Still, the recipes change slightly. In addition to the change in fermentation, the hops also shift. Chimay surprisingly prefers American hops, and have used Galena in the past. They now use Cluster hops. Interestingly, they don't use whole hops but extract--because Chimay is designed to lay down and age, the monks prefer extracts, which hold their aroma and bitterness longer than whole hops.
Chimay is such an elegant beer. It has a heady, refined aroma and that rich, deep color; the head is a silky latte hue. There's a reason this beer sells well in the United States--it is so approachable, but neither tame nor simplistic. The flavor is a bit like desert--creamy and soft, vanilla notes and plum, and then the long finish, a little sharp with alcohol, just to remind you that this is an adult's beverage. Hops don't immediately announce themselves, but after a few sips, you realize they're actually quite assertive. Chimay is this way--you continue to find new depths. Later I found caramel and then cinnamon and then...
I don't know what the beer tasted like before they switched to closed fermentation--the change happened nearly 20 years ago. But if the Grande Réserve has suffered a "grievous" loss in the transition, it must have been an amazing beer. To me, Chimay is a confection--a glass of pure pleasure. It is excellent with cheese (which the monks of Sourmount also handcraft) but even better with chocolate. In fact, it could be that there's no better accompaniment. (Portlanders can experiment by going to a Pix Patisserie, where both chocolates and Chimay are available for side-by-side sampling.) Chimay's not the most sublime of the Trappists, but it's a world standard for good reason.
ABV: Red 7%, White 8%, Blue 9%
Hops: Cluster hop extract (Yakima Valley)
Adjuncts: Dextrose (5%)
Rating: Grande Réserve A-
Available: Readily available at beer stores and many grocery stores.