Ruby Red Grapefruit and Basil Sorbet

In a small saucepan , combine the grapefruit juice, simple syrup and the grapefruit zest and bring to a boil. Remove from the heat and add the basil leaves. Set aside to steep in for 5 minutes. Add the lemon juice to the sorbet base, strain through a fine mesh sieve and set aside to cool. Refrigerate until thoroughly chilled, then process in an ice cream machine according to manufacturer's instructions. Transfer to a freezer- proof container with a lid and freeze until firm, 6 to 8 hours.