Wash the grapes and lemon balm, pat dry, put both in the shaker and crush well with the pestle. Add pear juice, apple juice, lime syrup and 4 ice cubes to the shaker and shake well.
Pour the drink through the strainer into the cocktail bowl onto 4 new ice cubes. Garnish with a lemon balm stalk and serve immediately.
TIP: You can also add frozen grapes to the drink or stick grapes on the edge of the glass.