sinigrin(1−)

Horseradish (Armoracia rusticana, syn. Cochlearia armoracia) is a perennial plant of the Brassicaceae family (which also includes mustard, wasabi, broccoli, and cabbage). The plant is probably native to southeastern Europe and western Asia. It is now popular around the world. It grows up to 1.5 metres (5 feet) tall, and is cultivated primarily for its large, white, tapered root. The intact horseradish root has hardly any aroma. When cut or grated, however, enzymes from the now-broken plant cells break down sinigrin to produce allyl isothiocyanate, which irritates the mucous membranes of the sinuses and eyes. Once exposed to air (via grating) or heat, if not used immediately or mixed in vinegar, the grated mash darkens, loses its pungency, and becomes unpleasantly bitter-tasting.

small round seeds of various mustard plants

Species of plant (''Capparis spinosa'')

Species of flowering plants in the cabbage family Brassicaceae

Seeds of various mustard plants