TIL about one of the solvents involved, ethyl acetate, and the fact that it is not good for you. How do I know that my local coffee shop's machine is working correctly and provides only safe levels of this solvent?
There's probably more ethyl acetate in apple juice (it occurs naturally in fruit) than there is in the equivalent quantity of coffee. Because people freak out when they hear terms like "ethyl acetate", the industry has started calling this "sugar cane decaf".
"One of the common solvents, ethyl acetate, comes naturally in many foods and beverages. It’s considered a safe chemical for decaffeination by the Food and Drug Administration."
speaking from a chemist's perspective, ethyl acetate is basically non-toxic. it decomposes into ethanol and acetic acid (vinegar). dcm (methylene chloride) is toxic, but should be completely removed before it ever reaches you.
the nice thing about volatile organic solvents is that they're...volatile, so they are easily stripped from coffee beans.
I wouldn't expect a coffee shop to do the decaffeination there. Rather, the company that does the decaffeination is its own thing, which then ships their product to the roaster, which then ships their product to your local coffee shop.
It smells like nail polish remover, well nail polish remover with the acetone subtracted, and it is noticeable well below any toxicity threshold. It's also a characteristic component of some fruit / fermentation aromas
Ethyl acetate occurs in nature and breaks down into ethanol and acetic acid in the body. It has a very low toxicity in the levels encountered in coffee.