Making this sous vide G&T by A.J. Schaller at Sterling, Va.’s Culinary Research & Education Academy (CREA), Cuisine Solutions’ research arm, starts with a sous vide tonic syrup. Keeping infusions under 185°F is crucial, says Schaller. “This is the temperature at which the flavor of the volatile oils will change on the fruit and thicken the product,” she says. Starting with room temperature ingredients will also help with a more rapid transfer of flavors, according to Schaller.
*Sous vide tonic water: Add 4 cups water, 4 tsp powdered cinchona bark, 1 cup lemongrass, 1 roughly chopped lemon (with zest added and juiced), 1 roughly cut lime (with zest added and juiced), 1 roughly chopped orange (with zest added and juiced, 1 grapefruit (with zest added and juiced), 1 tsp allspice berries, 1/4 cup citric acid, 1/4 cup salt and half of 3/4 cup agave syrup to a sous vide bag. Cook in a water bath set at 158 degrees F for 2 hours. Strain the liquid several times through a chinois and coffee filter until clear, and stir in remaining agave syrup to taste. Cut with water (roughly 1 part tonic syrup water to 4 parts water), and carbonate in an iSi siphon.