In Europe and Asia, the sharp-tasting mustard seed has been used as a seasoning for food and as a medicine since ancient times. In the New Testament of the Bible, the tiny mustard seed is a symbol of the power of faith.
Scientists have placed mustard in the genus, or group, called Brassica. This genus includes many other food plants, such as broccoli, brussels sprouts, cabbage, and cauliflower. Unlike most spices, mustard is primarily grown in areas where frost may occur in winter.
There are three main types of mustard. Each comes from a different kind of plant. White mustard, also called yellow mustard, originally grew near the Mediterranean Sea but is now also grown on the Great Plains of North America. Brown mustard, also called Indian mustard, originally grew near the Himalayas in Asia. Black mustard comes from Europe and Asia but is no longer important as a crop. Leading mustard-producing countries are Canada, Nepal, and Russia.
A mustard plant has a soft green stem without any woody parts. It is an annual, which means that it grows for only one season and then dies.
Both white and brown mustard are planted in the spring. The plant grows rapidly and produces bright yellow flowers. The plant reaches its full height of 5 to 6 1/2 feet (1.5 to 2 meters) as its flowers fade. Many green seedpods then appear on its branches. Each pod of the brown mustard plant has as many as 20 seeds in it, while white mustard pods contain no more than eight seeds. They are harvested in early autumn.
The mustard plant is easy and inexpensive to grow. It flourishes in many different types of soil, resists insect pests and plant diseases, and tolerates harsh temperatures without serious harm.
Mustard seeds are almost round and about 1/10 inch (2.5 millimeters) across. They may be light yellow or dark yellow depending on the type of mustard. As long as they are whole, the seeds have no odor.
When the seeds are ground up and mixed with water, a chemical reaction takes place. In brown mustard, the product of this reaction is oil of mustard, which smells and tastes like strong mustard. In white mustard, the reaction produces a different kind of mustard oil. It has very little odor but produces a sensation of heat on the tongue. White mustard is milder than brown mustard.
Unbroken mustard seeds are sold for use as food. So is dry mustard, a powder that is prepared by cleaning, pressing, grinding, and sifting the seeds. Dry mustard is mixed with water before serving. Most people, however, buy mustard in the form of a paste. The paste includes spices, herbs, vinegar, wine, and starch along with crushed mustard seeds. Brown mustard seeds are used in French mustard. White mustard seeds are used in the milder American and German mustards. English mustard combines the two types of seeds.
Mustard is widely used to spice up various foods, particularly sausages and cold meats. It is also used as an ingredient in mayonnaise and salad dressing. Mustard greens—the leaves of the plant—are also cooked and eaten. In many parts of Asia, the oil of brown mustard is used for cooking. The solid that remains after the oil is removed is made into cakes that are fed to animals.
Mustard has long been used in medicine. The ancient Greek physician Hippocrates recommended mustard in his writings. Mustard plasters were once applied to the skin to produce a feeling of warmth. They were used for chest colds and other ailments. In addition, poisoning victims were sometimes given mustard seeds and warm water to drink. The patient would vomit up the mustard and—it was hoped—the poison as well.
