Categorizing or Tagging Visitor Comments

I have a section on my site that I want people to be able to post recipes etc..

Is there a way to sort of categorize or have the user tag the comment before posting so that I can display them in groups, tag clouds, or hooks for searching?

Thought about creating a drop down in the form that has – chicken, -pasta, -salad

etc…., but it seems like a lot of work for not knowing how I can even utilize this info.

Thanks in advance, I really appreciate any help!