Bitter Herb

The Last Supper took place on Passover, and the Christian Communion wafer goes back to the Passover matzo. Although it wasn’t required, medieval Christians sometimes ate another part of the Seder meal, the bitter herbs. The book of Exodus doesn’t spell out any particular bitter herb to use. Ashkenazi Jews decided on horseradish; medieval European Christians chose Tanacetum vulgare, better known as tansy.

They picked this member of the chrysanthemum family because its name comes from athanasia, the Greek word for immortality (referring to the fact that tansy’s button-like yellow flowers don’t wilt--they’re “everlastings”). The leaves were pressed and the juice was used to flavor eggs (themselves symbolic of resurrection), usually in a small custard tart that was also known as a tansy. In some parts of England, the village merrymaking on Shrove Tuesday was called a tansy too.

A lot of bitter things are hard on the body. Tansy contains two skin irritants and thujone, a toxin also found in sage and wormwood, which in excess can cause dizziness, ringing in the ears, numbness, trembling, delirium and even general paralysis. That’s why we’re biologically programmed to dislike bitter flavors.

In the Middle Ages, though, bitterness was valued. As a result, many people developed a positive taste for tansies and ate them at any time of year. As late as Jane Austen’s day, the English still commonly served tansies as side dishes to meat.