A Mustard Primer
Yet another reason to thank the Romans: mustum ardens (hot must), better known as mustard, is along with wine one of their important contributions to the culinary landscape of Europe. The production of mustard is intertwined with that of wine. Grapes put the “must” in mustard; must is grape juice from the first pressing of grapes which has not started to ferment. The hotness comes from Brassica nigra, Brassica juncea, or Sinapis alba (black mustard, brown mustard, and white or yellow mustard, respectively). Though mustard grew wild in the Celtic and Germanic regions of Europe and provided foragers with leafy greens, the technique of grinding the seeds to make a spicy paste is the legacy of the builders of a line of fortifications separating the Roman Empire from the Germanic tribes. Stretching from the North Sea to the Black Sea along the Rhine, Main, and Danube rivers, this line curiously enough still delimits the spread of viticulture in Europe.
Despite growing up in the land of burgers and hot dogs, it wasn’t until I spent time in France that I became a fan of mustard. While staying with family in Lyon, I would always look forward to the salad dressing à la maison, a mustard vinaigrette of oil, vinegar, and Dijon mustard that was mixed up every few days in a regular bowl, the remnants of which took their place in the refrigerator along with the ubiquitous plate of cheese. Recently I decided to prepare mustard from scratch. Why buy glasses of prepared mustard when it is so easy to make it yourself?
2 Tbs mustard seeds (I used Sinapis alba, yellow or white mustard. Indigenous to southern Europe, this is the least hot of the varieties mentioned above.)
1 Tbs very cold water
2 Tbs white wine vinegar
Starting with 1/2 Tbs, grind the mustard seeds in a mortar with a pestle until all seeds have been crushed. Do this a little bit at a time to reduce potential frustration, or find yourself a chemist who is used to this kind of work. You can see the mustard powder I ended up with below, a mixture of fine grains and husks.
Add 1 Tbs of cold water and stir to make a paste. Let the paste sit for ten minutes. This is the crucial step when the glucoside sinalbin reacts with myrosinase. Water is the catalyst and must be cold as heat damages the reaction. Don’t leave the spoon in the bowl – mustard is corrosive.
Add the vinegar and mix well. The vinegar sets the reaction in place. There’s no turning back now; the mustard will remain this hot.
Let the mustard sit one day to allow the bitterness to dissipate. Store in a container that will not corrode.
Keeps forever, but I’m sure it won’t last that long in your kitchen.
It looks quite innocent, but this mustard is very hot. I made a vinaigrette following a recipe with a ratio of 3 parts olive oil : 1 part mustard : 2 parts red wine vinegar, and it was too sour and strong since my mustard already has so much vinegar in it. Next time I plan on doing my normal 3 parts oil : 1 part vinegar ratio and using mustard in place of the vinegar.
Now it’s time for you to make the mustard! I’d love to hear how yours turn out. Meanwhile, the mustard seeds I planted on the balcony have sprouted, so there will be more mustard chronicles at a later date. No post next week because your humble mustard chronicler will be in a former Roman settlement on the Rhine.