If you have been A Coffee Person for any reasonable amount of time, you have no doubt that to explain to someone that actually coffee isn’t bitter, or at least it’s not supposed to be, but it’s really rather sweet. It’s basically a rite of passage into specialty coffeedom. Turns out, it may not just be that they are drinking bad coffee—though it may be that too—some folks may just be genetically more inclined to perceive bitterness compounds found in coffee, and it has nothing to do with caffeine.
Scheduled to be published in the journal Food Chemistry, researchers from the Technical University of Munich sought to examine how various compounds in coffee affect perceptions of bitterness individuals. They note that, while caffeine is often credited with coffee’s perceived bitter flavor, decaffeinated coffee is also considered to be bitter by consumers, thus that particular compound cannot account for the entirety of the sensation.
Instead they focused on a compound known as mozambioside, which The Week describes as “about 10 times more bitter than caffeine.” Mozambioside exists in green coffee that, during the roasting process, degrades into a variety of derivative compounds. Even still, some of those compounds can activate “two of the roughly 25 bitter taste receptors in the human body.” One of those taste receptors is known as TAS2R43.
For the study, researchers genotyped a panel of 11 trained tasters to determine the presence of the TAS2R43 gene. Seven of the individuals were heterozygous, meaning they had one allele of the TAS2R43 gene. Two individuals were homozygous in expressing the gene and two were homozygous in the gene’s deletion (they note that roughly 20% all Europeans don’t have the gene).
When given different types of coffee preparations and roast levels to assess the flavor of, participants with the intact homozygous TAS2R43 gene had a lower threshold of mozambioside-derivative compounds in a beverage for it to be perceived as bitter.
So maybe some folks are genetically inclined to perceiving more bitterness in coffee. Which is unfortunate for them. My suggestion? Drink better coffee and just power through.
Zac Cadwalader is the managing editor at Sprudge Media Network and a staff writer based in Dallas. Read more Zac Cadwalader on Sprudge.
