Heat the wine, lemon juice and sugar in a small frying pan over a high heat. When boiling, reduce to simmer for 3-4 minutes to thicken.
Add the grapes and simmer for three minutes. Remove from heat and pour into a shallow bowl.
In a clean bowl, beat the mascarpone, until soft, then fold through the lemon curd and zest.
To serve, top the grape mixture with a dollop of the cream and garnish with mint.