Tonic Syrup

Directions

1. 1
   In a medium saucepan, combine cinchona bark, lemon grass, lime zest and grapefruit zest.
2. 2
   Add grapefruit juice, lime juice, allspice berries and 2 cups water.
3. 3
   Simmer, covered, for 25 minutes.
4. 4
   Remove from heat and pass through a fine strainer lined with muslin or cheesecloth into a bowl.
5. 5
   Allow mixture to rest for at least 30 minutes, then carefully pour off liquid, leaving behind and discarding grainy particulates that have settled at bottom of bowl.
6. 6
   For each cup of the resulting tonic water, add 3/4 cup of sugar and 1 teaspoon citric acid.
7. 7
   Cover and refrigerate until used.