I'm brewing a sour stout (think The Bruery's Tart of Darkness) and I'm planning on adding cherries later on. The brewer who created the recipe suggested I use tart/sour cherry puree. Anybody know where to find it? I see a lot of sweet cherries, and it isn't too hard to find dried tart cherries, but the only place I've seen tart or sour cherry puree does so by the ton. That's probably a little too much.