Port wine be labelled as "port" or "Porto". In the United States, wines labelled "port" may come from anywhere in the world, while the names "Oporto", "Porto", and "Vinho do Porto" have been recognized as foreign, non-generic names for port wines originating in Portugal. Port is produced from grapes grown and processed in the demarcated Douro region. The wine produced is then fortified by the addition of a neutral grape spirit known as aguardente in order to stop the fermentation, leaving residual sugar in the wine, and to boost the alcohol content. The fortification spirit is sometimes referred to as brandy but
Giuseppe Verdi and third nights, the reception improved considerably). With Strepponi, Verdi went to Naples early in January 1858 to work with Somma on the libretto of the opera "Gustave III", which over a year later would become "Un ballo in maschera". By this time, Verdi had begun to write about Strepponi as "my wife" and she was signing her letters as "Giuseppina Verdi". Verdi raged against the stringent requirements of the Neapolitan censor stating: "I'm drowning in a sea of troubles. It's almost certain that the censors will forbid our libretto." With no hope of seeing his "Gustavo III" staged as