Watch | Guinness declares longest French bread at 400-foot in Italy

A judge from Guinness World Records has certified a 400-foot-long baguette baked at the Milan Expo 2015 as the longest in the world. Some bakers worked nearly seven hours on Sunday to bake the French bread, characterised by its soft middle and crusty exterior.Among the craftsmen were 20 citizens of the small Italian town of Magliano d'Alpi and seven artisan bakers from Paris.The giant baguette was baked in a portable oven which rolled along the length of the doughy preparation.The mobile oven rolled over the dough at a speed of about 20 meters (66 feet) per hour to bake it.After nearly six hours, the baguette was fully cooked and the Guinness World Records judge stepped in to do the measuring.Cheers went up as he declared the baguette the world's longest.The Italian maker of Nutella, Ferrero, backed Sunday's attempt to beat the 111-meter (364 feet) record held by a French supermarket chain.After the record ceremony was completed, the baguette was slathered with the hazelnut spread and shared with hundreds of Expo visitors.