What is the action? give (verb)
Who is doing the action? zookeepers (subject)
Zookeepers give what? Zookeepers give taste. (direct object)
To whom or for whom do the zookeepers give a taste? The zookeepers give wombats a taste (indirect object)
Let's look at the whole sentence:
Zookeepers(subject) give(verb) the(article) grown(adjective) wombats(indirect object) a(article) taste(direct object) of the wild(prepositional phrase).
Wombats is the indirect object in the sentence.
Hope this helps =)