Suze or Salers are the best options if you do not have Bitter Bianco to hand. Suze is a bitter French aperitif flavoured with gentian root, with a spicy, floral and citrusy taste. Salers is another French apéritif with a bitter edge to it. Made from gentian root, white wine and botanical flavourings. It is bold in flavour and slightly vegetal, so may not be to everybody's taste. Both options have a distinctive yellow hue so will result in a pale golden spritz cocktail. Nonetheless, they make acceptable Luxardo Bitter Bianco substitutes.