Would you say it were appropriate for a uni lecturer to say this?

[fayyive]

"all the bitches will be liking that!"

while speaking to a male student during class about the beard he (the student) grew?

Sounds like something out of Bad Education, with the mock rap referencing! Not professional at all.

As the only woman at this class, Fay, how did you feel about it?

If it had been me I'm not sure if offended is exactly the reaction I'd have had. It is inappropriate anywhere except as someone said in the context of discussing urban slang. I think I'd have thought sad, trying to hard to be cool, old git.

If I'd had my wits about me I would have liked to do a dramatic double take and "Oh my god what did you just say" with lots of eye rolling.

I would have raised an eyebrow
and slightly narrowed my eyes
deffo not acceptable