Discuss ABOUT?
We have discussions ABOUT things, but we simply DISCUSS, not discuss ABOUT. To discuss = to talk about. Therefore to discuss ABOUT = To talk ABOUT ABOUT.
"We would always discuss food quality."
However, as there is a WAS in the sentence perhaps one should write, "In my previous job WHAT my colleagues would always discuss WAS food quality." As in, "...the thing (that) they would discuss..."
Where on earth did this badly worded question come from? It's a confused mixture of 2 grammatical constructions. How can anyone give a correct answer unless they correct other parts of the sentence?