VATIS UPDATE Article

Researchers from the Second University of Naples, Italy, have developed a new way to identify counterfeit coffee by assessing the presence and quantity of a plant-specific chemical compound, known as homostachydrine. The new method employs existing, affordable techniques for chemical analysis, but goes a step further by isolating a plant compound that has specific concentrations in the different commercially available coffee bean varieties.

The new method developed by the scientists tests the percentage of Arabica and Robusta in a blend. It is faster, easier to conduct and uses relatively inexpensive equipment to measure the compounds in a liquid, similar to those used for doping tests. It involves mixing ground-up coffee in a water solution of formic acid and putting the liquid into a high-performance liquid chromatography (HPLC) instrument to identify the coffee’s homostachydrine quantities.

Results showed that the average homostachydrine content is 1.5 ± 0.5 milligrams per kilogram in Arabica beans and 31.0 ± 10.0 in Robusta beans. These values are as baselines in the identification of adulterated coffees. Another one of homostachydrine’s advantages is its high heat-stability, as it is extremely difficult to trace coffee fraud once the beans have been roasted. A similar test based on a different plant compound found in Robusta beans has already been certified by the German Institute for Standardisation, however, it is still cumbersome and less certain.