The genuine walnut is a deciduous tree from the walnut family, which produces aromatic nut fruits and is also valued as a supplier of fine plywood. Archaeological evidence indicates that the walnut has been used as food for more than 9,000 years. Originally, the walnut comes from the area between Persia and Kyrgyzstan to the outskirts of the Himalayan Mountains. The Greeks brought the tree to Europe in the sixth century BC. In the Middle Ages, walnut trees were cultivated in orchards. In 1770, Spanish missionaries brought the walnut to the New World, where commercial walnut production began almost 100 years later in what is now California.
The walnut tree is not very demanding on the ground and is common in all temperate regions of the world. The walnut is monoecious, each plant carries both male and female inflorescences, whose pollination is done by wind. In spring, the walnut is the last deciduous tree to bloom and thus forms a late fruit. Finished walnut kernels are usually available in November in the northern hemisphere. Walnut kernels are rich in linolenic acid, tocopherols and zinc. As a result, they have a protective effect in diabetes (type 2), high blood pressure and cardiovascular disease.
The world production of walnut kernels is over 850,000 tons. Main supplier countries are China, the US (California), Chile, Iran, Ukraine and France. Because of their size and light colour, Chilean and Californian walnut kernels are particularly popular. Walnut kernels are used in cakes, bread and ice cream. Especially appreciated are French chaberts, which are used to top quality chocolates. Walnuts in the shell are popular items around St. Nicholas’ Day.