Police said the group graduated from a course taught by the National Olive Oil Association Unaprol that included instruction on how to taste fake extra-virgin olive oil and how to determine the geographical origin of olive oil by subtle differences in taste, ANSA reported Friday.

"This initiative will strengthen the defense of the quality of one of the symbols of the Mediterranean diet," Unaprol head Massimo Gargano said.

Gargano said training the task force would send "an unequivocal signal" that oil producers are dedicated to ensuring quality.

Olive oil producers in Italy won a battle this year to make sourcing a mandatory part of the labeling on bottles.