To Mix Mustard
To half a cup of ground mustard add one tablespoonful of sugar, five of vinegar, pepper and salt to suit the taste; little water or olive oil may be added.
A working formula for prepared mustard from dry powder, of the kind kept in a covered pot on the sideboard. The proportions are terse, so a few things are worth spelling out.
- The hinge: liquid temperatureThe enzyme reaction that creates mustard's heat needs cold liquid and about ten minutes to develop. Cold water gives a sharp, nose-clearing mustard; hot liquid or an immediate flood of vinegar arrests the reaction and yields something milder and flatter. Mix with cold water first, let it stand, then work in the vinegar.
- "Five of vinegar"The recipe almost certainly means five tablespoonfuls, carrying over the unit from the sugar. Half a cup of dry mustard against five tablespoons of liquid makes a very stiff paste, which is presumably why the closing clause offers more water or oil. Extra liquid will be needed for a spreadable consistency.
- Ground mustardThis is dry mustard powder, not the jarred prepared kind. Plain yellow mustard flour is what is meant; commercial powders cut with wheat flour or turmeric will behave differently.
- RestingFreshly mixed mustard is harsh and bitter. Cover and leave it at room temperature for fifteen minutes to an hour, then refrigerate; the raw edge softens over a day or two.
- Yield and keepingAbout two-thirds of a cup. Sealed in a jar in the refrigerator it keeps for a month or more, though it loses pungency steadily. Make small batches.
Before prepared mustard in jars became a supermarket staple, the household bought mustard as a dry yellow flour and mixed a small quantity as needed, exactly as here. Commercial milling of mustard seed into fine powder is generally traced to eighteenth-century England, and the Colman firm of Norwich made the powdered form a fixture of British and American pantries through the nineteenth century. Mixing it fresh had a practical logic: dry powder keeps almost indefinitely, while made mustard fades within weeks, so the cook produced only what the week's table needed. The sugar and the option of olive oil here mark it as a table mustard for cold meats rather than the fierce plain water-and-powder mixture used medicinally in poultices, which came from the same tin.