Walnuts are rounded, single-seeded stone fruits of the walnut tree commonly used for the meat after fully ripening. Following full ripening, the removal of the husk reveals the wrinkly walnut shell, which is usually commercially found in two segments (three-segment shells can also form). During the ripening process, the husk will become brittle and the shell hard. The shell encloses the kernel or meat, which is usually made up of two halves separated by a partition. The seed kernels – commonly available as shelled walnuts – are enclosed in a brown seed coat which contains antioxidants. The antioxidants protect the oil-rich seed from atmospheric oxygen, thereby preventing rancidity. Walnut trees are native to eastern North America but are now commonly grown in China, Iran, and within the United States in California and Arizona.
Walnuts are late to grow leaves, typically not until more than halfway through the spring. They secrete chemicals into the soil to prevent competing vegetation from growing. Because of this, flowers or vegetable gardens should not be planted close to them.
Walnuts are most often eaten on their own as a snack but can also be added to salads, pastas, breakfast cereals, soups, and baked goods. They’re also used to make walnut oil — an expensive culinary oil frequently used in salad dressings. There are a few edible walnut species.
Walnuts are also a good source of manganese, copper, magnesium, phosphorus, vitamin B6, iron. They are high in monounsaturated and polyunsaturated fats and omega-3 fatty acids. They are also a good source of protein. Nuts have a reputation for being a high-calorie and high-fat food. However, they are dense in nutrients and provide heart-healthy fats. The combination of healthy fats, protein, and fiber in walnuts helps to increase satisfaction and fullness. This makes them more healthful as a snack, compared with chips, crackers, and other simple carbohydrate foods. The possible health benefits of walnuts may include boosting the cardiovascular system and bone health, reducing the risk of gallbladder disease, and treating epilepsy.
How to Store
For long-term storage, it is best to buy unshelled nuts and place them in the refrigerator for two to three months or freeze up to one year. If using in a short time period you can keep in the pantry.