Though known as sardina in Italian because of its sardine-like shape, Alosa agone (synonym Alosa fallax lacustris) is actually a freshwater fish, twaite shad. Found in many Alpine lakes, around Lake Iseo the fish is preserved using an unusual technique. Every day the fishermen go out at sunset to set their nets, returning at dawn to draw them in. The fresh fish are then salted for 48 hours before being left to dry for around a month somewhere shady and well ventilated. After the drying they are arranged in containers, pressed to drain off the fat and covered in olive oil, then left for at least four months. They are usually eaten lightly griddled and served with polenta.
Fishing in Lake Iseo is hard work and not very profitable, and the activity risks disappearing. Additionally, overfishing and the lack of repopulation initiatives mean that catch volumes are in decline.
Only fish caught and air-dried between December and March are preserved.