In The BFG, he describes frobscottle, a fizzy drink where the bubbles fizz downwards instead of up. Upward-fizzing bubbles make one burp, something the giants in the book find ‘filthsome’. Sophie, the heroine, takes issue with the alternative.
“With frobscottle,” Sophie said, “the bubbles in your tummy will be going downwards and that could have a far nastier result.”
“Why nasty?” asked the BFG, frowning.
“Because,” Sophie said, blushing a little, “if they go down instead of up, they’ll be coming out somewhere else with an even louder and ruder noise.”
“A whizzpopper!” cried the BFG, beaming at her. “Us giants is making whizzpoppers all the time! Whizzpopping is a sign of happiness. It is music in our ears! You surely is not telling me that a little whizzpopping is forbidden among human beans?”
“It is considered extremely rude,” Sophie said.
“But you is whizzpopping, is you not, now and again?” asked the BFG.
“Everyone is whizzpopping, if that’s what you call it,” Sophie said. “Kings and Queens are whizzpopping. Presidents are whizzpopping. Glamorous film stars are whizzpopping. Little babies are whizzpopping. But where I come from, it is not polite to talk about it.”
“Redunculous!” said the BFG. “If everyone is making whizpoppers, then why not talk about it? We is now having a swiggle of this delicious frobscottle and you will see the happy result.” The BFG shook the bottle vigorously. The pale green stuff fizzed and bubbled. He removed the cork and took a tremendous gurgling swig.
“It’s glummy!” he cried. “I love it!”
For a few moments, the Big Friendly Giant stood quite still, and a look of absolute ecstasy began to spread over his long wrinkly face. Then suddenly the heavens opened and he let fly with a series of the loudest and rudest noises Sophie had ever heard in her life. They reverberated around the walls of the cave like thunder and the glass jars rattled on their shelves. But most astonishing of all, the force of the explosions actually lifted the enormous giant clear off his feet, like a rocket.
“Whoopee!” he cried, when he came down to earth again. “Now that is whizzpopping for you!”
(Roald Dahl – The BFG 1982)