Peel the ginger and grate finely, pour 1/2 liter of water over it and let stand covered for 1 hour.
Pour the water through a sieve into a large bowl. Pour another half a liter of water through the sieve with the ginger. Add the sugar, the lemon juice, the pineapple juice and the grated nutmeg, stir well.
Fill juice into bottles and store in the refrigerator. It stays there for up to a week.