From The Food Encyclopedia by Jacques Rolland and Carol Sherman
A blend of ground shelled peanuts, vegetable oil and salt, originally devised by a St. Louis physician to nourish elderly patients and invalids. In 1903, Dr. Ambrose Straub patented a peanut-grinding machine. At the St. Louis World's Fair the next year, peanut butter was first introduced to the North American public, although Peruvians and Africans have been enjoying peanut paste for centuries. The process to keep the oil and peanut butter from separating was invented in 1923. It was vegetarian John Harvey Kellogg who really began to promote peanut butter in the early 1900s. His brother, Will, who founded the cornflake empire, then took up the torch.
