Framboise (pronounced “frahm bwoz”) is a French word meaning raspberry and “frambozen” is a Flemish word meaning raspberries. When speaking of beer, either of these words is used to refer to a very old style of lambic beer that is made with raspberries. Framboise has traditionally been brewed in the small towns west of Brussels, Belgium, in an area known as Pajottenland.
Mashing is carried out to optimize the growth of microorganisms associated with spontaneous fermentation and favor high levels of free amino nitrogen and unfermentable sugars. After boiling, the wort is transferred to a coolship, a shallow, large open tank generally located near the roof of the brewery. There, the wort is cooled and allowed to be inoculated by airborne microorganisms which begin the spontaneous fermentation. Brewing traditionally takes place only in the colder months of the year so that the wort can cool quickly—that is, in 1 to 2 days—using only the ambient air temperature. Brewing in the warmer months results in the wrong microflora causing “infection” in the beer.
After the wort has started fermenting, it is transferred to oak barrels, where the lambic finishes fermenting. After aging for one season (about 6 months to 1 year) raspberries are added into the oak barrels, where a second fermentation begins. The raspberry addition is traditionally with whole fruit, but today many lambic breweries add a mixture of whole fruit and syrup, or only raspberry syrup. When adding whole fruit, the framboise undergoes another aging period from 1 month up to 1 year, often depending on the needs of the marketplace. Fruit flavor, aroma, and color diffuse into the beer during the barrel aging. The framboise is then bottled and may be aged another several months before being released for sale. When a brewery adds raspberry syrup, the process is much quicker and the framboise can be ready for packaging almost immediately.
Some versions of framboise are very fragrant and can be rich in the natural aroma of raspberry, while other versions have a slight artificial raspberry aroma that has more of a raspberry jam-like character. Either way, the aroma is unmistakably that of raspberry accompanied by the unusual “funky” ester profile found only in lambic beers. In taste, all framboise show raspberry flavors, and like other lambic beers they can be mildly or highly acidic. Perhaps the most distinguishing feature of framboise is the differing level of dryness in various marketplace examples. Some traditional framboise, such as that from the Cantillon Brewery in Brussels, are very dry, quite tart, and full of raspberry character. Other more modern examples, such as those from Belle Vue and Lindemans, have sweetness added to balance the sour taste. Over the years, brewers have used sweeteners ranging from saccharine to corn syrup. Bottled versions of sweetened framboise must be pasteurized. Sugar has long been offered at cafés to allow customers to sweeten their own beers, but most traditionalists look down on lambics that are sweetened at bottling.
The presentation of framboise is often in a small-volume, fluted glass much like a champagne flute. This style of glass highlights the slightly pink to deep red color of the beer and allows the consumer to take in the visual aspects of the beer as well as the rich aroma.
Brewers around the world, and particularly craft brewers in the United States, have recently been inspired to attempt to replicate framboise and other Lambic beer styles. So far, their success has been limited, perhaps because of differences in the mix of microorganisms found in the air in breweries and barrels outside Pajottenland. Lambic purists claim that the correct blend of microflora is part of the unique Senne Valley terroir, and the European Union has shown their agreement by the issuance of an appellation contrôlée for lambic beers.