It's not in the Florida Statute. For the reasons below, I'm going to tell you what I think, rather than what I know. Normally, 'depraved mind' can include malice for a specific individual (which can be formed just before the killing), malice for a group (which doesn't have to be racial - it could be Kiwanis, fat people, Ohio State fans, or - punks who look like they are casing or robbing apartments, if the prosecution can show that.
You would need evidence - early run-ins with the person or class, writings about them, expressions of hatred or frustration toward them. Something more than 'people who wear leather pant in public look silly.'
Because I'm not currently practicing law and much of the research I do for work is not legal, I'm not currently on a flat monthly fee for Westlaw or Lexis. I pay by the search and I haven't paid to run a search on this statute (it will make more sense to see what cases have interpreted parts of this statute after we know more about what Zimmerman may have told the police during his multi-hour interview, or what the prosecution is alleging).
What I'm telling you is general with respect to a 'depraved mind' or 'depraved indifference' and not Florida law.
The terms 'depraved mind' and 'depraved indifference' cover more than just the above.
Thanks for the primer! California uses malice in the statute, then implies malice when the circumstances show an “abandoned and malignant heart”. Heart.. mind.. to each his own.