(Decanter) - Italian authorities have employed a local oenologist to combat the rising problem of 'fake' Prosecco being sold in the Veneto region.

Winemaker Andrea Battistella was asked in June this year by the agricultural ministry to investigate, and report venues to the authorities who are selling imitation Prosecco from carafe or on draft.

Roberto Cremonese, export manger for producer Bisol in the Treviso region told decanter.com that at least 30% of DOC Prosecco sales were now estimated to be based on illegal wines.

'Much of the Prosecco found in bars in the region is produced artificially with the addition of C02 and sold on draft from beer kegs. The fault lies with the distributors, who often willingly market undrinkable wines.'

'It is a major concern for us, as it can really damage Prosecco's image,' he added.

According to Dario Poddana of wine importer Les Caves De Pyrene, the changes to the Prosecco appellation framework in 2009 have exasperated the problem of counterfeit wines being sold.

'After the removal of the Prosecco IGT designation, growers under the new DOC rules had to reduce their yields to an output of 180 hectolitres per hectare from the previous 250,' Poddana said.