Protected designation of origin—better known by its initials ‘PDO’—is a mark to legally protect the designation attributed by the European Union to foods whose particular quality characteristics depend essentially or exclusively on the area where they were produced.
For a product to be PDO, the production, processing and manufacturing stages must take place in a delimited geographical area. The producers of PDO products must follow strict production rules established by specific production regulations. Compliance with these rules is guaranteed by an independent control body.
In short, it guarantees that the product was grown and prepared in the production area (particular microclimate) indicated by the production regulations according to the techniques stated in these regulations.
(source Wikipedia)