What spice in brown mustard is it that tastes like cinnamon and horseradish (each at different times)?

How Gourmet Mustard Enhances Food Tastes

Mustard since time immemorial has fascinated the mankind.  The gourmet mustard has not only provided taste but has also due to its unique medicinal properties as helped many too get rid of scores of diseases.  It has lot of religious and cultural significances.  The Romans, the Greeks, the French, the British; name any country and [...]