Put on gloves, as the tannins in the nuts will turn your hands black. Wash fresh green walnuts thoroughly and prick all around with a needle.

Place them in a bowl and fill with water. The first week change the water twice a day; I did it once in the morning and once in the evening. The water is initially quite brownish to black, and after about three weeks, it remains clear.

From the second week, change the water only once a day. Repeat this procedure for 2 – 3 weeks to remove the tannins and bitter substances, so your green walnuts do not taste bitter later.

The walnuts will float on the surface; first, you can weigh them down with a plate and a whole can.

Mine took three weeks before they turned black, and the water stayed clear.

Finally, pour boiling water over the green walnuts; after about ten minutes, transfer them to a kitchen strainer and rinse with cold water. In this way, the last remains of the tannic acid are removed.

After three weeks, first, prepare the sugar syrup. For this, bring the sugar and water to a boil.

Add the spices, except for the lemon juice, to a tea/spice strainer* and boil until the sugar is completely dissolved and the mixture is clear.

I kept the walnuts in whole; some people slice them or quarter them. Add to the sugar syrup along with the lemon juice and simmer for another 15-30 minutes until the walnuts are soft but not mushy. 

Pour into mason jars. The green walnut preserves should be well covered with syrup.

Seal the jars airtight and store them in a cool, dark place.

After the jar is opened, the green walnut preserves will last the longest in the refrigerator.