So apparently I have a similar contorted expression to my mother when eating sour food.
My father always referred to this as my mother's-maiden-name-gene. Let's say her maiden name was Chaplin, he would say "Ah there's that Chaplin gene again!"
Being young I misunderstood this as a verb, ie. I was "chaplinging".
Cut to first year of school where I proudly waltz around informing any classmates eating fizzy sweets that the correct and proper term for their reaction is "chaplinging". It was a few years until the penny dropped.