Before mustard was a condiment, it was a poultice for bronchitis and toothaches, an ointment for skin inflammation, and a powdered additive to a soothing, sleep-inducing bath. As early as the 5th century BCE, the Greeks prized the easy-to-grow plant for its antiseptic properties and ability to stimulate blood circulation. Scientist Pythagoras found that the essential oils, when applied to a wound, pulled toxins from the body, which led him to use mustard as a treatment for scorpion stings. Physician Hippocrates applied mustard plasters to chests and let the heat from the dressing loosen phlegm and ease breathing.
Around the 4th century CE, the Romans had a new idea. They mixed young wine with the crushed seeds of the medicinal plant, tasted the paste, and named the new flavor sensation “flaming hot must.” Long before the Silk Road opened to Europe, mustard (mustum being the Romans’ unfermented grape juice, and ardens the Latin for “fiery”) was one of the continent’s first breakout spices, and it soon spread to the rest of the world.
Because of its antibiotic properties, an unopened jar of mustard will rarely spoil. It doesn’t require refrigeration, will not develop mold or bacteria, and will never become unsafe to eat. Coupled with the distinctive zing that flatters everything from Indian curries to American hot dogs, dim sum to barbecue sauce, nearly every region in the world has developed their own application for the spicy, versatile, and medicinal plant.
In the French city now synonymous with the condiment, they made their mustard with verjus, the tart juice of unripe grapes, which made a sharper, more sophisticated variety soon coveted around the country. The Duke of Burgundy, an avid 14th-century mustard lover, held a gala where guests reportedly consumed 85 gallons of Dijon in a single sitting. Pope John XII of Avignon declared a new Vatican position called Grand Moutardier du Pape, or Grand Mustard Maker to the Pope, and appointed his nephew, believed to be a dilettante living near Dijon, to mix all his mustards. (The idiom “the pope’s mustard maker,” which refers to a pompous person in an insignificant role, came from this appointment.) By 1855, a man named Maurice Grey was winning awards for his Dijon-mustard-making machine, the first of its kind to automate the process. He sought out a financial backer and found Auguste Poupon. Together, combining their last names to form the Grey Poupon brand, they rolled out their signature Dijon, prepared with white wine and manufactured at high speed.
Jeremiah Colman, an English miller, pioneered the technique of grinding mustard seeds into a fine powder without allowing the oils to evaporate, which preserved the spicy, intense flavor. In 1866, Colman became the official mustard maker to Queen Victoria and later, during World War II, his mustard was one of the few foods that wasn’t rationed because it was essential to flavoring bland wartime food.
The 14th-century dukes of Milan were trendsetters in mixing sweet and spicy. Chunks of fruit such as apples, quince, or cherries were preserved in sweet and hot mustard syrup, then served atop their ducal roasts. In Italy today, the term mostarda refers to the hot and fruity condiment.
Traditionally, Bengalis had elaborate rituals surrounding the harvest and washing of mustard seeds to make the traditional mustard relish, kasundi. On a spring day called Akshaya Tritiya, groups of married women bathed in odd numbers, then washed the mustard seeds facing east, chanting in wet saris. Over the next week, the seeds were ground into a pulp, spiced, and mixed with water, salt, and green mango, before fermenting in a clay pot. Originally, only Brahmins (the highest Indian caste) were allowed to make the mustard sauce, but it’s now open season for kasundi making. The spicy chutney is the preferred dipping sauce for fried foods, especially the beloved Bengali vegetable fritter, called a chop.
This thick, pungent paste inflames the nasal passages like horseradish or wasabi. There is no special ingredient to the mixture, just ground brown mustard seeds (Brassica juncea, or Chinese mustard) mixed with water. After about 15 minutes, the paste reaches peak potency, then slowly declines. A good swap for Chinese mustard powder is Colman’s, which is a blend of Brassica juncea and the slightly milder white mustard, Sinapis alba.
Excerpted from Gastro Obscura: A Food Adventurer’s Guide by Cecily Wong and Dylan Thuras. Workman Publishing © 2021.