Dish: A cocktail in motion at Quill

Wednesday, December 8, 2010; 12:30 PM

IT'S ALIVE! IT'S ALIVE!: Order the Elderflower Royal at Quill, the plush lounge tucked into the Jefferson Hotel downtown, and what you get is one of the city's more animated cocktails. Some of the movement comes from bubbly prosecco, which is mixed with St-Germain, the aromatic French liqueur made with elderflower blossoms. But waving from the bottom of the flute are reddish-purple fronds with the texture of gelatin and the flavor of black currants, or what the fall drink menu refers to as "molecular cassis."

The science behind the elegant, edible streamers? Head bartender Luca Marcellin, who created the festive drink to bridge an unseasonably warm autumn and a chillier December, says he cooks cassis with gellan, a gelling agent (used by El Bulli in Spain, among many other avant-garde restaurants). The resulting goop is poured into a mold the size of "three iPhones put together" and cooled. When a patron orders his twist on a kir royale, Marcellin uses a special zester to shave long strips from the jiggly-firm bar.

The drink, though popular right up until Thanksgiving, when I encountered it, didn't make the jump to the brand-new winter menu. However, Marcellin says he'll continue to honor requests for the lively libation, which costs $15, through January. Included in the price: Quill's fat green Italian olives and fancy mixed nuts - snacks almost as quick to disappear as the sips.

- Tom Sietsema

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