For many people, mustard is the yellow stuff that’s slathered on sausages; the word may bring to mind an oft-repeated television commercial for Grey Poupon. Some cooks are resourceful enough to prepare their own from the dry powder that’s available at grocery stores, but most of us simply select our favorites at the supermarket. Many of us experienced mustard in childhood as a plaster for treating chest colds—until Vicks came to our rescue. And to some people, mustard is just a weed. Nearly everyone has a relationship with mustard, and its pungent taste and stimulating irritation have been with us down through the ages.
An Ancient Condiment
The use of mustard seeds as food has been recorded as far back as the Han Dynasty in China (206 B.C.–A.D. 221), and these spicy seeds probably were a popular condiment well before the beginning of recorded history, in Europe as well as in China. They were eaten whole with meats in ancient Egypt, and the Greeks and Romans sprinkled the powdered seeds on their food. Some historians believe that Roman garrisons introduced their customary use of mustard to England; others maintain that mustard seed arrived there in the droppings of migratory birds. Most likely, both stories are true. In the Bible (Luke 13:19), reference is made to a mustard seed that grows into a tree, as a seed of black mustard (Brassica nigra) certainly might in the climate of the Middle East.
The medieval French prepared culinary mustard by pounding the seeds with honey and either vinegar or must (unfermented grape juice, or “new wine”). The word “mustard”, or moutarde in French, derives from the Latin mustum ardens, “burning must”. Mustard’s immense popularity in Europe during the Middle Ages may have resulted partly from its effectiveness in disguising the taste of spoiled food, but that can’t be the whole explanation: guests at a fete given by the Duke of Burgundy in 1336 are said to have consumed 70 gallons of prepared mustard in one sitting.
Whereas the French prepared their mustard condiments by soaking the seeds, then grinding them and sometimes straining out the hulls, the English took a different approach. They ground their mustard seeds coarsely with flour and sometimes a little cinnamon, moistened the resulting oily paste, and formed it into balls, which were then dried. The cook would reconstitute a mustard ball by mixing it with a liquid, usually vinegar.
When tropical spices arrived in Europe in the sixteenth century, mustard’s popularity decreased for a while, but mustard making was still taken very seriously, especially in France. By the middle of the seventeenth century, the mustard makers of Dijon, in Burgundy, had organized into a guild, and the guild’s regulations required each maker to keep only one shop in town so there would be no doubt as to the origin of any bad mustard.
Early in the eighteenth century, a Mrs. Clements of Durham, England, became renowned for her very fine mustard powder. Her simple secret, which she kept for years, was to grind the seed in a hand mill, then pass it through a sieve to remove the hulls. Pale yellow English mustard powder is sold today in most supermarkets. Mixed with cold water and allowed to stand for about 10 minutes, it takes on an excellent clean, sharp taste.
Today, mustard is the leading spice worldwide: more than 300,000 metric tons are produced each year. Although some mustard seed is pressed to produce an odorless fixed oil that is used in Indian and other cookery, most of it finds its way into the familiar condiment. Dijon still produces half the world’s prepared mustard—although much of the seed is imported from Canada—and Dijon mustard, with its clear, hot, sharp taste, is the one most often referred to in French recipes. The numerous mustard variations in France, including the dark tarragon-flavored mustards of Bordeaux, show that country’s predilection for this condiment.
Growing Your Own Mustard
The seeds used in prepared mustard come from three species of the cabbage family (Cruciferae) (see The Culinary Mustards, page 36). All are native to Europe and Asia but are naturalized throughout North America. They all have rather sparse divided or toothed leaves; small clusters of four-parted, 1/2-inch-wide yellow flowers; and narrow pods up to 11/2 inches long containing several tiny round seeds. The seeds remain viable in the soil for many years, germinating immediately when exposed during cultivation.
It takes a lot of mustard plants to produce significant amounts of seed, but a dozen plants should yield enough to make at least a couple of batches of prepared mustard (see the recipes on page 37). In cooler climates, sow mustard seed in early spring in rich, moist, well-drained soil. Where winters are mild, sow it in the fall to mature the following spring. If your soil is poor, work in abundant compost. Mustard grows everywhere as a weed with no care whatever, but it will grow better if you pamper it a bit. Plant seeds 1/8 to 1/4 inch deep and thin seedlings to about 9 inches apart. You can use the tender greens and thinnings as a potherb or salad green. Older greens tend to be tough and bitter; they can be made more palatable by boiling them for a few minutes, then changing the water and continuing to boil for a total of 30 minutes. The clusters of small yellow flowers appear in a month or so, followed by slender green pods. Seeds mature anywhere from 60 to 95 days from sowing. The pods must be harvested as soon as they begin to turn from green to tan, or they will burst and scatter their cargo of seeds. (Outside the mustard bed, they are an unwelcome weed.)
The easiest way to harvest mustard seed is to pull the whole plant out of the ground and hang it upside down in a dry place with its head inside a paper bag. Within two weeks, the seedpods should be dry, and you can give the stalk a good shake to release the seeds into the bag. Another method, somewhat more labor-intensive, is to pinch off the pods, spread them in a single layer on fine screening or cheesecloth, and allow them to air-dry for about two weeks. The pods will open readily when dry, and the perfectly round seeds can be easily separated from the pods by placing all on a tilted, slightly coarse surface. Store the seeds in tightly covered jars.
It seems that flea beetles are attracted to mustard as strongly as humans are. Tiny buckshot holes in the leaves are evidence of their presence even if you don’t see any of the shiny little black insects themselves. Flea beetles do the most damage when the seedlings are small. One strategy for outwitting them without using pesticides is to sow the seeds thickly and delay thinning the seedlings until they seem to be growing faster than the beetles can eat the leaves. Another approach is to plant a trap species—some kind of plant that flea beetles like even better than they do mustard. Spider flower (Cleome hasslerana) is a possibility.
The characteristic “heat” of mustard—in food and in mustard plasters—develops when the seeds, whole or powdered, are mixed with cold water. This causes a reaction between two components of the seed—the enzyme myrosinase and the mustard oil glycosides, called glucosilinates —which produces a sugar and several chemical irritants. The reaction begins immediately and continues for several minutes.
This reaction occurs somewhat differently if mustard seeds are mixed with hot water: at temperatures greater than about 110°F, the reaction produces somewhat toxic irritants called nitriles. These compounds, also produced in small amounts by boiling cabbage and other common Brassica species, apparently are a matter of little concern, but they may account for the bitterness that often results from adding unsoaked mustard seeds to a dish early in cooking. Salt and vinegar added to unsoaked seeds also impart a bitter taste. However, if the seeds are first soaked in cold water, vinegar and salt will stabilize and enhance the flavor (see recipes, page 37), and cooking will not produce bitterness.
Heating or soaking dry mustard seeds in oil, or heating the seeds in a dry pan, does not induce the same chemical reaction. Black mustard seeds are mild and nutty when heated in oil and are a delicious addition to Indian dishes, and all mustard seeds may be toasted in a dry skillet until they pop and then ground, as in many Indian spice mixtures (masalas).
Mustard as Medicine
The role of mustard in modern herbal medicine is mostly that of counterirritant. When applied externally or internally, it induces a low-grade inflammation in which blood vessels dilate, and this increases blood flow to the area. When mustard is taken internally, this superficial irritation of tissues in the mouth, esophagus, and stomach stimulates increased production of gastric acid. Once absorbed into the bloodstream, mustard’s irritants stimulate blood flow in all tissues; hence the familiar sensation of flushing and perspiration that often follows a hot, spicy meal. It’s no wonder that mustard is and has been considered a warming remedy.
A tea made by soaking mustard seeds (yellow, brown, or black) in hot water has been used to treat bronchitis, indigestion, and constipation, but it must be taken sparingly: mustard’s benefit stems from its irritant properties, and an overdose can damage tissues in the digestive tract. A mustard foot bath (made by infusing 1 tablespoon of bruised seeds per quart of water) is thought to be good for arthritis and to help reduce fever, and a mustard poultice (made by adding warm water to freshly ground seeds to form a thick paste) is often recommended for muscular or skeletal pain. If kept in contact with skin for too long, mustard will cause blistering. Early herbalists encouraged such blistering, believing that toxins were being drawn to the surface and could be removed by lancing the blisters, but modern herbalists generally reject that notion. Some recommend applying the poultice on top of a piece of cheesecloth moistened with water or olive oil to prevent the paste from sticking to the skin.
In large quantities or when used regularly as a staple, mustard depresses thyroid function, so persons with hypothyroidism should avoid frequent or excessive use.
The Lore of Mustard
In the early European floral calendar, the mustard flower was associated with the date June 18. However, in the traditional language of flowers, mustard sends a message of indifference, so this plant probably would be inappropriate in a bouquet for a friend whose birthday is June 18.
Mustard seed was once considered an antidote for ingestion of the poisonous herb henbane. An oil pressed from the seed hulls, a by-product of the manufacture of powdered mustard, was reputed to promote hair growth when rubbed on the affected area. Epilepsy, snakebite, and toothache are conditions that were thought, at one time or another, to be relieved by mustard.
Not surprisingly, mustard has been associated astrologically with the element fire. Early Hindus are said to have used mustard seed somehow to travel through the air, and at one time in European history, the seeds were thought to protect against sorcery and supernatural beings. Mustard seed buried under the doorstep supposedly protected a home from such evils. A recipe intended to protect one from sorcery while asleep called for equal amounts of flax seed and mustard seed to be mixed and placed on one side of the bed, and a pan of cold water to be placed on the other side. Carrying mustard seed in a red cloth sachet was also thought to increase the mental powers of the carrier.
Mustard in the kitchen
Flavors vary widely in commercially prepared mustards, and making your own mustard gives an opportunity to adjust them to suit your palate. Below are three variations that demonstrate the basics of mustard making and how to alter the flavorings. Where black mustard seed is specified, the more readily available brown mustard may be substituted, but the result will not be as pungent.
These prepared mustards contain no added salt and are quite low in sodium. A little prepared mustard mixed with a mild vinegar makes a delicious, fairly low-fat salad dressing. Adding yellow mustard seeds to pickles not only adds flavor but also inhibits molds and bacteria. Mustard is also useful as an emulsifier in mayonnaise and salad dressings.
Prepared mustard should be refrigerated and used within six months.
Seeds for Eating
• Yellow mustard seeds, whole and powdered, are available in grocery stores, and brown mustard in many health food and gourmet stores. Black mustard seeds may be more difficult to find but are sold in many Indian specialty markets.
• Adriana’s Bazaar, 2152 Broadway, Dept. HC, New York, NY 10023. Send SASE for catalog. Yellow and Indian black mustard.
• Sultan’s Delight, PO Box 253-H, Staten Island, NY 10314. Send SASE for catalog. Yellow and brown mustard.
• Frontier Herb & Spice Collection, PO Box 118-HC, Norway, IA 52318. Catalog free. Yellow and brown mustard.
Seeds for Growing
• Companion Plants, 7247 N. Coolville Ridge Rd., Athens, OH 45701-HC. Catalog $2. Tilney (yellow) and Borgonde (brown).
• J. L. Hudson, Seedsman, PO Box 1058-HC, Redwood City, CA 94064. Catalog $1. Brassica nigra.
• Redwood City Seed Company, PO Box 361, Redwood City, CA 94064. Catalog $1. B. nigra.
• Seeds for mustard greens are widely available from general as well as specialty seed houses.
Barbara Bassett is a prolific writer (seven books and more than 300 articles) and food developer from Gualala, California.