Blueberry Ice: In a blender or food processor, combine the blueberries and grape juice and pulse until mixed, about 30 seconds.
Working in batches, strain the mixture into a medium-size bowl through a medium mesh strainer. Add the maple syrup, lemon juice, and salt to the bowl and stir to combine.
Transfer the mixture to a 9- by 13-inch pan, cover it with plastic wrap, and freeze it for 1 hour. Remove the pan and scrape the mixture's frozen edges into the center with a fork. Freeze it another hour, then scrape the ice crystals into the center again. Return the pan to the freezer for at least 1 more hour, or overnight. If the mixture is too firm to scoop when you're ready to serve, scrape it to loosen the crystals. Makes 4 cups.
Lemon Ice: Bring the water, sugar, and salt to a simmer over high heat and stir until the sugar is dissolved. Remove the pan from the heat and stir in the lemon juice.
Pour the liquid into a 9- by 13-inch pan and let it cool to room temperature, about 15 minutes.
Cover the mixture with plastic wrap, then freeze and scrape as you did for the Blueberry Ice. Makes 3 cups.
Cover the mixture with plastic wrap, then freeze and scrape as you did for the Blueberry Ice. Makes 3 cups.
