1. Soak the gelatine in a bowl of cold water for 5 minutes. Meanwhile put the sugar and a 100ml of the wine in a pan and stir over a very low heat until the sugar has dissolved. Pour into a large jug.
2. Squeeze the gelatine leaves to remove excess water then stir them into the warm liquid. Stir in the remaining wine.
3. Divide the blueberries, raspberries, blackberries and red grapes among 4 glasses.
4. Pour in the wine mixture to just cover. Place the glasses in the fridge and leave for approx. 2 hours or until just set.
5. Serve straight away – the longer the jelly is out of the fridge, the more it will soften.