Whole mustard seeds have very little aroma, but when chewed they are slightly bitter and then the hot and aromatic taste comes through. In South Indian cooking they are often fried whole in oil until they start to pop and they become less pungent and their flavour nuttier and slightly bitter. Brown Mustard Seeds are an important ingredient the South Indian spice mixes such as Sambar Podi andPanch Phoron and in the north west of India raw seeds are often ground and used in pastes for curries. Most European mustards are made from brown seeds and the powdered seeds are popular for use in barbecue sauces.