Vermouth is an aromatized wine made from a neutral, dry white basic wine which is then blended with an infusion. The infusion which gives each vermouth its unique and distinctive character is created by flavoring the basic wine with a special selection of herbs flowers, fruit peels, seeds, plants and other botanicals. The addition of brandy fortifies the vermouth to 18% alcohol by volume. The prized and closely guarded recipe is used to make Boissiere has not changed since 1854.