For the Italian government, it seemed like a recipe for success: create an official "Made in Italy" logo to defend the country's finest food exports from an army of foreign impersonators. On supermarket shelves worldwide, a star-shaped logo would mark out real Italian cheeses, hams, pasta and sparkling wines from those that only look or sound Italian, such as Parmesan made in New Zealand or Prosecco bottled in Brazil.

But Rome has discovered that even the simplest recipe can go wrong. Instead of unifying Italy's food industry against a common enemy that is bagging billions of euros in sales, the government's proposal for a Made in Italy certification quickly created bitter divisions.