Here’s where it gets kind of nerdy but also makes rational sense: ketchup goes with fries because ketchup has the variety of flavors that fries lack. So fries can be salty and fatty – they have the crunchy and hot texture but not the flavor complexity that ketchup offers. Ketchup provides sugar, acid, a little tang and a little umami if you will. Its like – if fries are the empty canvas ketchup is the bright red graffiti. The fries and ketchup together just… wake your mouth up.
You can feel the perfect contrast. Crispy vs. saucy. Salty vs. sweet. Hot inside vs. cold temperature outside. Even if you don’t think about it you still perceive it and your brain is like, “yes! give me more of that.”
So Yeah. It’s Not Just a Habit. It’s a Full History.
Anyway, what started as fermented fish sludge in ancient China found its way to tiny plastic cups next to fast food fries from frozen streams in Belgium which had been wrongly named by American soldiers. And then these two strangers met in the back seat of a drive-thru now too far gone to care about where they came from.
So the next time you mindlessly dunk a fry into ketchup, without a second thought… well, there is something to be said that you are subconsciously contributing to centuries of flavor evolution. Not that you have to think about that exactly. But it is there, just underneath the fat from the fry and the sugar and salt from the condiment.
