I bought 2 1/2 pounds of grapes, slipped out the seeds, and pureed them in my blender. Once strained, this gave me about 3 1/2 cups of juice. It was a little more than I needed for the recipe, so I drank the extra straight. Mmmm!
The Saveur recipe has you simmer equal parts juice and water along with the sugar until the liquid is slightly reduced. Since the juice gets diluted again with more water when transferred to the bottle, my guess is that this step is here to dissolve the sugar and then caramelize it a bit. This would give the soda a richer and more complex flavor. (Most other DIY soda recipes just combine the straight juice with a simple syrup.)
The next step is to stir in the yeast and let the soda sit for twenty-four hours to let the yeast get going. The recipe doesn't mention it, but I'd recommend letting the soda cool to room temperature before stirring in the yeast since temperatures over 110° will kill yeast. The next day, you pour the juice in a bottle, top it off with water, and screw on the cap. When the bottle is rock-hard, that is the sign that the soda is fully carbonated.
Waiting for the soda to chill was the hardest part of this whole recipe. But my reward was a super-fizzy, intensely-flavored soda a million times better than what you buy in the store. The grape flavor was, indeed, very rich and nuanced. The carbonation added a crispness to the whole sip. Personally, I could have used a shot of something tart, like lemon juice, to balance out the sweet grape flavor. But overall, this grape soda tasted like the real deal.
The one major problem I had with this soda was not a fault with the recipe per se, but something that I've experienced with almost every homemade soda I've made: over-carbonation. When you first open the bottle, the release of pressure causes the soda to bubble up like mad and gush out of the top. Even turning the cap by tiny degrees to let the pressure out slowly, I still had grape soda gushing out the top. I ended up losing about a third of my soda down the sink as I opened the bottle.I'd been hoping that letting the soda sit for 24 hours before bottling it might help with this issue. Yeast is usually most active in the first 24-48 hours after being added to a liquid, as the beer brewers among us can attest. I thought that maybe bottling the soda after this period had passed might help create less extreme pressure build-up in the bottle, but apparently not. If anyone has any insight about soda carbonation and how to get it just right, I'd love to hear it!
All in all, this is a great recipe. It tastes very close to store-bought...but better! I think kids would definitely enjoy it, and it would make a great non-alcoholic alternative for adults at dinner parties.
• Get the Recipe: Concord Grape Soda from Saveur
(Images: Emma Christensen)