Nuts are dried fruit that have kernels or seeds encased in a hard woody shell or rind. There are many specific kinds of fruits included in the category of ?nuts? and also many that really are not true nuts. People eat many kinds of nuts and some such as the coconut have long been recognized as an important food source. Many kinds of nuts contain valuable substances such as oil and minerals. There are nuts that grow wild and are gathered from the plants, but some such as the peanut, are cultivated in very large quantities. Peanuts are sold as nuts and are also processed into peanut butter.

Nuts as Food

The peanut is by far the most popular nut used for food. Other popular nuts are cashews, walnuts, almonds, pecans, pinons and pistachio nuts. The breadnut is also popular and is often ground into flour to use in making bread. Most of these nuts contain between 50 and 70 % fat and oil and from 15 to 30 % protein. They also contain starch, Vitamin C and the B vitamins, including thiamine, riboflavin, and niacin. Walnuts and pecans also include Vitamin A. Nuts are a healthy part of the diet and are included under the Meat and Protein section of the food pyramid.

Nuts as a Source of Oil

There are valuable oils in many kinds of nuts. Generally, these oils are divided into two groups ? drying oils and non-drying oils. When drying oils are exposed to air they form a thin elastic film. The nuts in this category are English walnuts, candlenuts and oiticicas. They are used in the manufacture of paint, printer's ink, linoleum, oilcloth and patent leather. Non-drying oils are always in a liquid state at room temperature. The nuts in this category include peanuts, coconuts, cashews, pecans, filberts and pili nuts. They are used in the manufacture of lubricants and lighting as well as in making margarine, and soap.

Other Nuts

There are some nuts used in the tanning process. These nuts include bitternut, acorns and pecans. Other nuts, such as beechnut and acorn are used as livestock feed and the betel nut is often chewed as a stimulant.