The phrase "gulping down" is correct and usable in written English.
It can be used to describe the act of consuming food or drink quickly and eagerly.
Example: "After the long hike, he was gulping down water as if he hadn't had a drink in days."
Alternatives: "devouring" or "downing".
They may add a dash of lemon and hot sauce before gulping down each glistening blob.
Another is gulping down trolley cars like popcorn, and all three set about leveling San Francisco.
The sound of Choudhury gulping down water echoes from the headset around the room's microphone system.
And the crowd seemed to be greedily gulping down every last variant of his sound.
The story ends with Neil gulping down a beer, giving the reader the impression that this is his new obsession.
Bay Area eaters are eagerly gulping down Vietnamese noodle soup, or pho, typically made with beef or chicken broth.
Hardly a minute went by without someone gulping down a sentence and running to the side of the boat".
I would never dream that an appropriate classroom setting was one where the students were gulping down food.
But she has bitten off more than she can chew and I don't mean by gulping down a testicle.
"I hereby declare," said the returning officer after a cliffhanger that had the whole country gulping down Mogadon.
Inside the volunteer fire service headquarters in Whittlesea, an exhausted John Holmes was gulping down dinner after a 12-hour shift.
