How to cook
Most suitable are white grapes.
The grapes are washed and removed from their stalks. Choose large, evenly sized ones which are cleared from the seeds with a needle.
From the sugar and water, a thick syrup is prepared. The grapes are put into this syrup.
Boil the jam until the fruit is cooked and the syrup thickens. Add and dissolve the tartaric acid in hot water, and boiling for a further 2-3 minutes.
Let the boiled jam stand for 5-6 hours in a dish then pour into jars.