Soak bread in grape juice and squeeze dry in hands.Put meat 3 times through mincer, add bread and put through mincer again. Add all other ingredients, except chicken fat, and knead for 10 minutes. Wet palms of hands with leftover grape juice and shape mixture into small balls.Heat fat to boiling point and put in balls. Reduce heat to low and cook until both sides are well browned, about 30 minutes for whole operation.