Pungency , commonly referred to as spiciness, hotness or heat, is a sensation that contributes to the flavor of certain foods such as chili peppers. Highly pungent foods may be experienced as unpleasant. The term piquancy (/ˈpiːkənsi/ PEEK-ən-see) is sometimes applied to foods with a lower degree of pungency that are "agreeably stimulating to the palate". In addition to chili peppers, piquant ingredients include wasabi, horseradish and mustard. The primary substances responsible for pungency are capsaicin (in chilis), piperine (in peppercorns) and allyl isothiocyanate (in radishes, mustard and wasabi).