There are over 40 different varieties of mustard plants, but three are the most popular for culinary use. The black, brown, and white mustard seeds are the ones that typically go into making mustard around the world. All three varieties have become naturalized to North America and can be found in nearly every state in the U.S. as well as many provinces in southern Canada. All parts of the plant are edible, including seeds, leaves, and flowers.
Mustard is the second most-used spice in the United States, as its usage is only exceeded by the peppercorn. And it's no wonder since mustard works well with all types of meats, pork, poultry, and seafood. You may be used to standard yellow prepared mustard, but there are many wonderful varieties of seeds and prepared mustards to experiment with.
Black Mustard Seeds
Brassica nigra is the plant that produces black mustard seeds, with nigra being Latin for black. It is in the same genus as cabbage and turnips and is an annual plant. It is native to North Africa and parts of Europe and Asia. The black mustard seeds are the ones used since ancient times by the Romans and they are thought to be the type of mustard seeds mentioned in the Bible. Not only that, the black mustard seeds are likely the ones that gave their name to mustard. In medieval France, they were mixed with unfermented grape juice (must) and called mout-ardent (burning must), which transformed into moutarde in French and mustard in English.
Black mustard seeds are still very popular in the Middle East and Asia Minor where they originated. The seeds are removed from their seed coats and are very small. They can be ground into spice or used whole, often added to hot oil to bring out the flavor.
Brown Mustard Seeds
Brown mustard seeds come from Brassica juncea, with juncea meaning rush-like. It is also often called Chinese mustard, Indian mustard, or Oriental mustard. Brown mustard originated in the Himalayans and has virtually replaced black mustard in American and British kitchens, particularly in North American Chinese restaurants. There are different varieties of brown mustard seeds, ranging from those with a dark brown seed coat to those that are dark yellow.
Brown mustard seeds are spicier than yellow mustard seeds, as can be seen in most types of brown mustard condiments. Brown mustard seeds are used in Europe to produce Dijon mustard and other specialty mustards. The usual table mustard in Russia is made from brown mustard seeds. Brown mustard seeds are used in Asian countries to produce condiments and mustard oil. As this mustard oil can have toxic erucic acid, it is not imported to the United States.
White (Yellow) Mustard Seeds
Yellow mustard comes from the seeds of the white mustard plant, Sinapis alba, with alba meaning white. While it is in the Brassicaceae family, it is not as closely related to the other two types of mustard as they are to each other. This mustard plant originated in the Mediterranean area and can be cultivated in colder climates as well as warmer climates, which may be a factor in its popularity. The white mustard plant bears light tan seeds that are a little larger than brown mustard seeds. These end up as the bright yellow mustard you probably apply generously to your hot dogs due to the addition of turmeric or dye.
White mustard seeds are milder than brown or black mustard seeds. They still contain pungent flavor producers, especially sinalbin. Their heat differs from black and brown mustard seeds in that the heat stays mainly on the tongue rather than traveling up the nose. The heat is also shorter-lived than those varieties. In addition to being ground to make a mustard condiment, they can be toasted to add to dishes or used for pickling.
Finding Mustard Seeds
If you shop the spice section of a typical grocery store you should be able to find yellow mustard seeds from American companies such as McCormick. These are also the mustard seeds in common pickling spice blends. Brown mustard seeds may be found at specialty spice stores such as Penzeys, online, or in Asian specialty stores. Black mustard seeds can often be found at Indian specialty stores.