Peanut butter is a food paste made from ground dry roasted peanuts, which is sold as either “crunchy” or “smooth”/”creamy” variety. Major consumer-brand peanut butter contains hydrogenated vegetable oil to stabilize it and prevent oil separation, salt to prevent spoilage, and dextrose or other sweeteners to enhance flavor. Peanut butter marketed as natural or organic might only contain peanuts and salt.[citation needed] Although some organic and natural varieties use palm oil instead of hydrogenated vegetable oil to prevent oil separation. It is popular in North America and the Netherlands, where it is used mainly as a sandwich spread, and a key ingredient in the peanut butter and jelly sandwich, as well as peanut butter flavored chocolate bars. Peanut butter may also be added to desserts such as cakes and biscuits. The United States and China are leading exporters of peanut butter. January 24 is National Peanut Butter Day in the United States. In some types of peanut butter, chocolate, jelly, or other ingredients may be added. Peanuts are native to the tropics of the Americas, and were mashed to become a pasty substance by the Aztec Native Americans hundreds of years ago.

Evidence of peanut butter as it is known today comes from US patent #306727, issued in 1884 to Marcellus Gilmore Edson of Montreal, Quebec, Canada, for the finished product of the process of milling roasted peanuts between heated surfaces until the peanuts became into “a fluid or semi-fluid state.” As the peanut product cooled, it set into what Edson explained as being “a consistency like that of butter, lard, or ointment.” Edson’s patent is based on the preparation of a peanut paste as an intermediate to the production of peanut candies. While Edson’s patent does not describe the modern confection we know as peanut butter, it does show the initial steps necessary for the production of peanut butter. J.H. Kellogg, of cereal fame, secured US patent #580787 in 1897 for his “Process of Preparing Nutmeal,” which produced a “pasty adhesive substance” that Kellogg called “nut-butter.” Dr. Ambrose Straub, a physician in St. Louis, Missouri pursued a method for providing toothless elderly with protein in the 1890s. His peanut butter making machine was patented in 1903.