Nah.
3 seconds sound clip from the Christmas Vacation (1989) movie soundboard.
You can hear this line at 00:13:10 in the Blu-ray version of the movie.
Quote context
[...]
- You set standards that no family event can ever live up to.
- Parties. Weddings. Anniversaries. Funerals. Holidays. Vacations. Graduations.
- You should be looking at a nice fat Christmas bonus this year, huh?
- Word is you're an excellent choice to be named Food Additive Designer of the Year.
- Nah.
- What's that new thing you got at Food and Drug?
- What it does is it coats and seals the flake, prevents the milk from penetrating it.
- Yeah. It's a beautiful product. I like it, yeah.
[...]