Our Finest Manjula's Spices brand of Ajwain/Carom Seeds in 250gm are the seeds of the ajwain herb, or Trachyspermum ammi. ... Although referred to as "seeds," carom seeds are the fruit of the ajwain herb. They're slightly green to brown in color and have a pungent, bitter taste. They look similar to cumin seeds, but their taste and aroma are closer to that of thyme.