You’ve probably heard about volatile compounds in coffee from barista championships. In recent years, competitors have begun squeezing espresso from frozen balls to trap and retain more volatile compounds, particularly volatile aromatic compounds. In miniature, volatile compounds create many of the subtle flavors in coffee.
Scientists are currently using them to determine the country of origin of coffee. Using a combination of gas chromatography and artificial intelligence, researchers are able to catalog the characteristics of coffees from specific countries of origin to accurately assess the origin of subsequent samples.
As reported Chromatography onlinethe recent study is the work of Italian and American researchers and is scheduled to be published in the journal . To do this, they tested 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 focusing on specific compounds so that the most common compounds, even unknown ones, could assist define the samples. They did this using a process known as two-dimensional gas chromatography, creating images of the levels of volatile compounds in the samples.
Using computer vision, a form of artificial intelligence that analyzes and interprets visual information, samples from each country were combined to create a composite template of the most common compounds of origin. Using these templates, they were able to accurately determine the origin of subsequent samples based on the volatile compounds expressed in them.
While somewhat restricted in scope – it’s unclear how factors such as coffee variety and post-harvest processing will impact the templates – the study could have huge benefits for the coffee industry. Not only can it identify origin, but it can offer a more objective assessment of coffee quality based on the volatile compounds it contains. And while it’s tough to imagine that gas chromatography will ever truly replace the customary cupping protocol, with all its subjectivity and human error, it could nonetheless be another useful tool for more uniform assessment of coffee quality.
