“Mozzarella di Bufala Campana” is a traditional Italian cheese, made only from water buffalo milk and exclusively in certain regions of Italy. Since water buffalo milk is expensive, there are falsely labeled mozzarella cheeses on the market which contain cow milk instead of water buffalo milk. Finding these adulterated products usually involves analyzing proteins or DNA in the cheese. However, these methods are time-consuming and often do not give quantitative information about the ratio of cow milk to water buffalo milk.

Alessandra Gentili and colleagues, University of Rome “La Sapienza”, Italy, have developed a method for the fast identification of fake water buffalo mozzarella. The team used the fact that cow milk and water buffalo milk contain different small molecules that can be used as biomarkers. Cow milk, for example, contains β-carotene, which is not detectable in water buffalo milk. Ergocalciferol, in contrast, is only found in water buffalo milk. The researchers used liquid chromatography−tandem mass spectrometry (LC-MS) to measure the amounts of these compounds in extracts of mozzarella samples.

Using this approach, the team was able to detect cow milk concentrations as low as 5 %. The method is simple, cheap, and could be used for a fast preliminary screening with high throughput.

• Screening and Assessment of Low-Molecular-Weight Biomarkers of Milk from Cow and Water Buffalo: An Alternative Approach for the Rapid Identification of Adulterated Water Buffalo Mozzarellas,
  Chiara Dal Bosco, Stefania Panero, Maria Assunta Navarra, Pierpaolo Tomai, Roberta Curini, Alessandra Gentili,
  J. Agric. Food Chem. 2018.
  https://doi.org/10.1021/acs.jafc.8b01270