Walnuts are round, single-seeded dupes or stone fruits from the walnut tree. After it ripens fully, the removal of the husk reveals the wrinkly walnut shell, which is usually found in two segments. During the ripening process, the husk will become brittle and the shell becomes hard. The shell encloses the kernel, which is usually made up of two halves separated by a partition. They are commonly available as shelled walnuts.

Walnuts belong to the tree nut family such as almonds, cashews, hazelnuts, pistachios, chestnuts, and other nuts. It's believed that the walnut tree dates as far back as 700 B.C. In the 4th century AD, the ancient Romans introduced the walnut to many European countries where it has been grown ever since. The walnut that we are commercially used to today is native to India and parts around the Caspian Sea. Called the English walnut, it was named after the English traders who carried it around the world for trade. The black walnut is another variety that is specific to North America. Walnuts are now grown in China, Iran, and within the United States in California and Arizona.

The walnut tree has an average lifespan that is about 150 years and outlives any human being on this planet. Its uses include food, medicine, shelter, dye and lamp oil. Walnuts can be eaten as it is, made into pickles or walnut butter. Walnuts are also popular in brownie recipes, cakes, pie, ice-cream toppings, and even as a garnish in certain dishes.

Walnuts will go sour and stale if they are stored in warm temperatures, but if kept in the fridge, they will last for weeks. Fresh walnuts smell slightly nutty and taste sweet, but those that are stale smell like paint thinner. Walnuts can also be roasted, either in the oven or on the stove. Another way of having walnuts is by making walnut milk, which can be used as a creamy base for smoothies.

China is the largest producer of walnuts in the world. In the year 2016-17, China accounted for 50% of the total world production. In India, walnuts are produced in the northern and north-eastern states of Jammu & Kashmir, Uttaranchal, Himachal Pradesh, and Arunachal Pradesh. Jammu & Kashmir is the largest producer of walnuts in India.

Some basic facts about Walnuts:

• Botanical Name: Juglans Regia (English Walnut)
• Family: Juglandaceae.
• Common Name: Walnut, Akhrot
• Parts Used: The kernel of the walnut is what is mostly used. However, the shell and the leaves are also said to have health benefits.
• Native Region and Geographical Distribution: Although walnuts were once native to India and parts of North America, they are now grown commercially in China, Iran, Turkey, Mexico, Ukraine, Chile, and the United States.
• Interesting Fact: Walnuts were considered as a food for the gods during the early Roman times, and were named after Jupiter – hence the scientific name Juglans regia.

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