Moutarde de Dijon

Dijon mustard is the prepared mustard of Dijon, Burgundy, where the city was the center of mustard making in the late Middle Ages and was granted exclusive rights in France in the seventeenth century. Wikipedia documents its first recorded use at the table of King Philip VI in 1336. The mustard assumed its current form in 1856, when Jean Naigeon, a Dijon mustard-maker, replaced the usual vinegar with verjuice — the acidic juice of unripe grapes — which gives a milder, more complex flavor than vinegar-based mustard. Modern Dijon mustard is made from brown mustard seeds (Brassica juncea) ground with a mixture of white wine, vinegar, water, and salt designed to imitate the original verjuice; the seeds are not all ground to a paste, giving the mustard its characteristic texture.

A spoonful of Dijon mustard is pale yellow-brown, smooth or slightly grainy, with a sharp, pungent aroma and a clean, vinegary heat that clears the sinuses. The flavor is more complex than ordinary yellow mustard — the wine and verjuice give an underlying fruitiness and depth; the heat is brisk rather than fiery, fading quickly to leave a savory, slightly bitter finish. Used as a condiment with all meats, or as a base for sauces and vinaigrettes.

Dijon mustard rests on the chemistry of mustard seeds and the choice of liquid. Brown mustard seeds (Brassica juncea) contain a glucosinolate called sinigrin; when the seeds are crushed and mixed with a liquid, an enzyme called myrosinase converts sinigrin into allyl isothiocyanate — the pungent compound that gives mustard its heat. This reaction requires water and is activated by crushing; the choice of liquid matters: Naigeon's innovation of using verjuice (or its modern imitation of white wine and vinegar) instead of plain vinegar gives a milder, more complex pungency than vinegar alone, because the wine's aromatics and lower acidity modulate the reaction. The heat is brisk rather than lingering because allyl isothiocyanate is volatile and dissipates quickly. The seeds are not fully ground — some are left partly intact — which gives Dijon mustard its characteristic slightly grainy texture and a pop of flavor when bitten.