Jam from green walnuts for the winter

Unusual and very healthy – young walnut jam. Many housewives do not know all the intricacies of making such jam, therefore they do not undertake to cook it. Ingredients: 1 kg of green walnuts;1 liter of water;2 kg of sugar;zest of 1 lemon;1 tsp citric acid;1 cinnamon stick;