When you do hit.getNode() does it return anything? If it returns a node you should be able to do a
node.getProperty("jcr:mimeType"). If not you might need to get the resource and then adaptTo(Node.class) to get at the properties. It seems to me I've done this before, I'll look around to see if I can figure out where I've retrieved mime types.
Using hit.getNode() then getProperty("jcr:mimeType") does not work. It does not even return 'jcr:title' or 'jcr:description'. I dumped out all properties included in hit and hit.getNode() but mimeType is just no where to be seen.
What properties are returned? That might be a little more telling. Also were you able to do anything like this:
Resource res = hit.getResource();
Node resNode = res.adaptTo(Node.class);
I can't imagine that would work if .getNode() doesn't work but you never know. Also, does hit.getPath() return anything?