Mostarda di frutta (sometime also called mostarda) is a Northern Italian condiment made of candied fruit and a mustard-flavoured syrup. Commercially the essential oil of mustard is employed, which has the advantage of transparency; in home cooking, mustard powder heated in white wine may be used.
Traditionally mostarda was served with boiled meats, the bollito misto which is a speciality of northern Italian cooking. More recently it has become a popular accompaniment to cheeses.
Mostarda di Cremona or mostarda cremonese (from Cremona) is made with several kinds of fruit, and is the version that typifies mostarda di frutta.
Mostarda di Mantova (also called mostarda di mele campanine or mostarda mantovana) is made from small, sour green apples called mele Campanine.
Another notable mostarda is mostarda vicentina, which is a specialty of the town of Vicenza (Veneto); it is characterized by a jam-like consistency and the use of quince (mele cotogne) as its main ingredient.
Other versions include mostarda di Voghera, mostarda siciliana, and mostarda bolognese.