Whole mustard seeds have little or no aroma. The hot taste which gives mustard its ‘bite’ is released only when the seeds are crushed or ground and mixed with water. This activates an enzyme present in the seeds, and it reacts with other natural constituents to produce the essential oil which gives the characteristic taste.

Mustard is an indispensable ingredient in cooking. Yellow mustard seeds are used primarily as a pickling and preserving spice, and in marinades. Black and brown mustard seeds are used in India in curry powders and in spiced ghee (baghar or tadka). Ground yellow mustard powder is used in salad dressing and mayonnaise, where it helps the emulsification of the egg yolk and oil.