One of the hallmarks of the single origin specialty coffee movement has been appreciation for specific varieties within the Arabica coffee species.
Like Pinot Noir or Cabernet Sauvignon wine varieties, coffee varieties such as Bourbon, Pacamara or Gesha are not used merely as identifiers; They are also used as marketing terms, but what if that 91-point gesha in your cup is actually 91 points from something else? The forbidden paradise.
Research published last month that determines the accuracy of the genetic labels of thousands of coffee plants from fingerprints suggests that misidentifying varieties both on farms and even in nurseries can be vast.
“DNA fingerprints provide a powerful new tool to different actors within the coffee industry, producers can verify the identity of the varieties they grow, roasters are able to ensure that what their advertising claims in relation to varieties is correct and, above all, those seeking to establish a more professional and reliable seed industry have a new monitoring instrument to establish and review the genetic purity of the seed bank and greenhouse plants ”, the authors of the study affirm. freely available in the Journal of AOAC International.
Behind the study is the Portland, Oregon-based non-profit organization World Coffee Research, which should be noted has a keen interest in promoting this type of DNA fingerprinting. The group launched a DNA fingerprint service for arabica coffee authentication in 2017 and charges $ 130 per sample.
For the recently published study, researchers applied DNA fingerprint testing to more than 2,500 coffee samples with this database, which comes from numerous sources, including the central WCR collection and anonymous samples submitted by individuals, samples from countries coffee producers around the world.
In one of the most absolute examples of genetic nonconformity, only 39 percent of the 88 samples identified as the famous gesha variety (often spelled geisha elsewhere) turned out to be truly gesha.
The researchers discovered the existence of incidental cross pollination on farms as a possible reason for the genetic ambiguity present on farms and nurseries.
“Experience with the WCR genetic database points to the conclusion that a recently selected variety in a region with a relatively organized research and nursery network shows greater genetic compliance,” the authors write. “Currently, the best example Of this, it is the Marseillaise variety that has 91% genetic conformity. However, when the varieties are older or research and nurseries are poorly organized, the percentage of genetic compliance can decrease dramatically. “
See here the full open access study.
Nick Brown is the editor of the Daily Coffee News for Roast Magazine.