Pastes made from mustard seeds have been used to flavor food since ancient times. The seeds from the mustard plant have been known about for at least 4000 years, making it one of the oldest spices in the world. There are three different species of mustard plant. Their seeds are virtually odorless, but they vary in flavor depending on the type. White mustard seeds are mild and nutty and develop a pleasant heat during cooking, while black mustard seeds have a hot kick and a bitter flavor. The taste of brown Sarepta mustard seeds lies somewhere between the two other types. The name “white mustard” refers to the white seeds. This mustard is also often called “yellow mustard” on account of its yellow flowers.