01 - Combine sugar and water in a small saucepan. Heat over medium heat, stirring until sugar is fully dissolved. Remove from heat and cool to room temperature.
02 - In a mixing bowl, combine orange juice, lemon juice, lime juice, orange zest, lemon zest, and salt. Stir in the cooled syrup.
03 - If desired, incorporate the vodka or limoncello and mix thoroughly.
04 - Refrigerate the mixture for at least one hour to evenly cool.
05 - Pour the chilled mixture into an ice cream maker and churn according to the manufacturer’s instructions for 20 to 25 minutes, until thick and frozen.
06 - Transfer the sorbet to a freezer-safe container, cover, and freeze for a minimum of three hours until fully set.
07 - If an ice cream maker is unavailable, pour mixture into a shallow tray, freeze for one hour, then stir vigorously with a fork. Repeat stirring every 30 minutes until smooth and frozen.