Old coffee is coming back to save the business (and the species tastes great, too)

The Scientist toasts the rediscovery of Coffea stenophylla, a relative of the C. arabica coffee plant our society runs on – that’s proved itself able to cope with some of the climate-change problems, like warmer growing seasons and increased diseases, that are now threatening our coffee supply:

Arabica, which makes up more than half of what goes into the world’s coffee mugs, grows best from 18–22 °C and is thus vulnerable to rising temperatures. Robusta, while more amenable to warmer climates, is generally considered not to taste as good as Arabica, and it garners lower prices for farmers.

Stenophylla has not been cultivated since the 1920s, with historical records indicating that it fell out of favor because of poor yields and competition with robusta, the authors write in their paper. It continued to grow in the wild, but until the current study, no sightings had been reported outside of Ivory Coast in decades.

In late 2018, Aaron Davis of the Royal Botanic Gardens in the UK and his coauthors found stenophylla growing wild in Sierra Leone. After acquiring some beans, they set up a taste test comparing the coffee to Arabica and robusta; 81 percent of the 15-judge panel mistook the stenophylla for Arabica. The authors write in their study that “the judges identified a complex range of tasting notes for stenophylla . . . including those popular or desirable in high-quality Arabica: stone fruit (peach), soft fruits (blackcurrant, mandarin), honey, light black tea, jasmine, spice, floral, chocolate, caramel, nuts, English candy and elderflower syrup.”

Davis predicts the species could be cultivated in Sierra Leone and make it into shops in five to seven years.

You can read the research here, in Nature Plants.