You’ve probably heard of volatile compounds in coffee from barista championships. In recent years competitors have started pulling espresso shots over frozen spheres to trap in and retain more volatile compounds, volatile aromatic compounds in particular. In short, volatile compounds are the things that create the many subtle flavors in coffee.
And researchers are now using them to help determine a coffee’s country of origin. Using a combination of gas chromatography and artificial intelligence, researchers are able to catalog attributes of coffees from specific origin countries in order to accurately assess the origins of subsequent samples.
As reported by Chromatography Online, the new study is the work of Italian and American researchers and is set to be published in the Journal of Chromatography. For it, they examined 32 different roasted coffee samples provided by Illy—five from Brazil, six from Colombia, and seven each from Ethiopia, Guatemala, and India.
They then created an “untargeted fingerprint” for each, a comprehensive chemical profile created without targeting any compounds in particular, thus allowing the most prevalent compounds, even unknown ones, to help define the samples. They did this using a process known as two-dimensional gas chromatography, creating images of the volatile compound levels in the samples.
Using Computer Vision, a form of artificial intelligence that analyzes and interprets visual information, the samples from each country were combined to create a composite template of the most frequent compounds for the origins. Using these templates, they were able to accurately determine the origin of subsequent samples based on the volatile compounds expressed by it.
Though somewhat limited in scope—it isn’t clear how things like coffee variety and post-harvest processing will affect the templates—the research could be a huge benefit to the coffee industry. It can not just identify origin but has the potential to offer a more objective assessment of coffee quality based on the volatile compounds it expresses. And while it’s hard to imagine gas chromatography ever truly replacing the traditional cupping protocol, with all its subjectivity and human error, it could nonetheless be another useful tool for more uniform assessment of coffee quality.
Zac Cadwalader is the managing editor at Sprudge Media Network and a staff writer based in Dallas. Read more Zac Cadwalader on Sprudge.
