Decaf Coffee

Love your morning latte? Or afternoon frappé? You’re not alone. Coffee’s one of the most-consumed drinks in the world, second only to water. 

Most of us enjoy the jolt of caffeine that comes with a cup of joe. But some people aren’t so lucky. Instead of providing a perk, caffeine can cause anxiety, insomnia, diarrhea . . . and other unpleasant stuff. For this reason—and probably more—it’s estimated that 12% of global coffee consumption is decaf.  


There are several different ways to decaffeinate coffee. The most common methods involve soaking unroasted coffee beans and adding a solvent to draw the caffeine out of the bean.

If you enjoy your java sans caffeine, you may want to stop reading now. But if you want to know more, here’s some detail:

  • Ludwig Roselius first discovered decaf in Germany in 1903 when a shipment of coffee beans got swamped with seawater. 
  • Roselius went on to invent the first commercial decaffeination process, which involved steaming the beans in an acid bath and using benzene (a chemical found in crude oil, gasoline, plastics, detergents, drugs and pesticides) as a solvent.
  • Benzene turned out to be carcinogenic, so it was replaced by other solvents like methylene chloride (also used as a paint stripper and a degreaser) and ethyl acetate (nail polish remover).
Benzene - the chemical used to make coffee decaf

Drink decaf but kept reading anyway? Be assured that this process has been given a clean bill of health by government regulation bodies. Still, many argue that the process affects the flavor of the beans and robs coffee of nutrition (yes, coffee is nutritious—find out more here

There are other methods of decaffeination that use things like activated charcoal filters and carbon dioxide pressure (for more information, check out this BBC article) but they’re pretty pricey and not 100% effective. So the search has been on for an alternative. And now, we just might have one.


The idea behind it is simple: instead of taking caffeine out of coffee beans after they’re grown, why not grow beans that have no caffeine in the first place? Although scientists have been working on this for over two decades, a new method of gene editing is making it reality.

Using CRISPR, a UK company called Tropic Biosciences has successfully created a naturally decaffeinated coffee bean by editing the plant’s genome. Coffee plants make caffeine from a natural chemical (xanthosine) through a three-step process carried out by the genes in the cell. Knock out one of those genes through CRISPR gene editing and the plant can no longer make caffeine. But it can still make coffee beans full of flavor and nutrition.  

Caffeinated banana?

Tropic Biosciences is also using CRISPR to edit the genome of the Cavendish banana (the kind most commonly found on supermarket shelves) so it’s resistant to disease. If that goes well, who knows what might come next. A caffeinated banana? 

If you want to know more about how CRISPR works and what other things it could be used for, pick up CRISPR: A Powerful Way to Change DNA . The book, which includes a crash course on genetics, will hit the shelves (and the mailbox) September 8, 2020 .  It’s available for pre-order through Annick Press , online retailers and your local bookstore.  

Image credits: eommina (, PiNkOpHiLiC (Deviant Art), Pppoooiii3 (Wikimedia Commons)