- I thought you said they were called Vogons.
- Vogons.
- Not Dentrassi?
- No. Dentrassi are the in-flight caterers.

7 seconds sound clip from The Hitchhiker's Guide to the Galaxy (1981) - Episode 1 sitcom.

You can hear this line at 00:22:36.385 in the Blu-ray version of the TV Series.

Quote context

[...]

- Signed in triplicate, sent in, sent back, queried, lost, found, subjected to public inquiry, lost again, and finally buried in soft peat for three months and recycled as firelighters.

- The best way to get a drink out of a Vogon is to stick your finger down his throat.

- And the best way to annoy him is to feed his grandmother to the ravenous Bugblatter beast of Traal.

- What an extraordinary book.

- How did we get on board, then?

- The Dentrassi let us on board.

- I thought you said they were called Vogons.

- Vogons.

- Not Dentrassi?

- No. Dentrassi are the in-flight caterers.

- Hey, hagra biscuit, the greatest!

- You'll love these guys. They cook the hoopiest frood food in the whole of the West Galaxy.

- Go on, have a bite. Go on, go on! Try it, try it. Your mouth will love you for the rest of your life.

- It's revolting!

[...]