Romans combined crushed mustard seeds with grape juice (called must) to arrive at mustum ardens, or "burning wine." From there, a simple contraction gives us "mustard."
From Mild to Wild
The pungent taste comes from a chemical reaction when mustard seeds are ground. Mixing in an acid like vinegar stops this reaction. So deciding when to add the acid can determine how hot the mustard becomes. Added immediately, the mustard is mild.
Mustards from Around the World
International mustards are characterized by exciting variety. American versions are mild and bright yellow with turmeric. English and Chinese mustards tend toward sinus-clearing heat. French mustard is stronger in Dijon, milder in Bordeaux. German mustards range from sweet and sour to hot.
The Mustard Man
Until the spice trade began, a European cook's spice rack was very limited. Since mustard was a local plant, it made for a cheap and plentiful spice. During medieval times, its importance was such that a mustardarius often graced European courts, supervising mustard preparations.
Homemade Mustard Recipes