Place this clip right after the gross reveal in your edit, then follow it with Eww Brother Eww as a second reaction in a different voice. Keep it after the visual payoff rather than before it, so viewers see the cause first.
Über diesen Sound
A short 1.4-second Italian voice clip of a speaker saying 'mi fa schifo,' the blunt phrase for saying something disgusts them. It lands as openly revolted and dismissive, turning instant disgust into a funny, exaggerated reaction that makes even a small gross moment feel dramatically worse than it is.