You can use frozen fruit instead of fresh — but not canned! Just thaw before pureeing.
For each concentrate, blend ingredients until smooth. Using a fine-mesh strainer, strain puree to remove any seeds or pulp. Refrigerate puree in an airtight container up to 1 week. When ready to use, combine with sparkling water to achieve desired sweetness and to give your soda plenty of “pop.”
Excerpt from "The Happy Cook" by Daphne Oz. Copyright © 2016 by Daphne Oz. Used with permission by William Morrow Cookbooks. All rights reserved.