In the end, the sugar sacks gave them away. Two Prosecco producers based in Valdobbiadene and Refrontolo, in the province of Treviso, were raided this past fall when officials grew suspicious after finding two tons of sugar in sacks. Italian police seized 750,000 liters of Prosecco from the two producers after they were found to have both added extra sugar to the wine during fermentation to increase the alcohol content, and to have exceeded their production quota. A third of the wine seized was thought to have extra sugar added to it during primary fermentation in order to increase its alcohol content. Sugar is permitted to be added to Prosecco and other sparkling wine during secondary fermentation, which with Prosecco happens in a tank, in order to sustain the yeast which is also added at the same time. Sugar can also be added at the end of the production process as a dosage. Sugar is usually mixed with wine and added in order to adjust the final sugar levels. Police chief Lieutenant-Colonel Vincenzo Nicoletti stated: “We believe the sugar was being added to about a third of the Prosecco seized, as it fermented, to boost its alcohol content, which is strictly forbidden”. The wine in question was likely turned into vinegar. The rest of the wine was seized as the wineries had exceeded their production quota. Nicoletti said that this was a particular problem in 2018: “Italian producers are in general going about 30% over the maximum production allowed.” Officials did point out that overall, there is an efficient system of controls in place. Out of 181 sparkling wine producers and 433 companies who vinify in the Conegliano Valdobbiadene Prosecco zone, there are just two firms in which an anomaly was found by supervisory bodies. They also emphasized that the use of sugar is a practice which is authorized by law when making sparkling wines, and although exceeding amounts is illegal, it is not physically harmful.