Reserve a few strawberries and/or orange slices if you’d like to garnish your drinks.
Cut the strawberries in half, sprinkle with sugar and let them stand for an hour to draw out as much juice as possible. At the halfway point, mash the strawberries with a potato masher to crush the berries and extract more juice.
Add orange juice, grapefruit juice, lemon juice and salt to the macerated strawberries.
Mix thoroughly, then press through a fine-mesh strainer, using the back of a spoon to extract as much liquid as possible.
If you like, keep the pulp - it is delicious in plain yogurt. Just store it in an airtight container in the refrigerator for up to 3 days.
Pour the syrup into a glass jar or bottle with a tight-fitting lid and refrigerate until ready to serve. For the brightest flavor and color, enjoy within 2–3 days.
I like a 1:1 ratio of syrup to bubbles. For an 8-ounce drink, use 4 ounces of syrup and 4 ounces of sparkling water..
Adjust the ratio and sweetness to your taste. Add a little more sparkling water for a lighter drink, more syrup for a stronger fruit flavor, or a squeeze of lemon juice if you'd like more brightness.
Serve over ice, in chilled glasses if you’re feeling fancy.
Garnish with strawberries or oranges for a special touch.