Don't you think that Chome wouldn't display you the content in readable format if it was compressed?
If you want to make sure, you can use a network sniffer like Wireshark, or use telnet:
[wanwizard@catwoman] $ telnet localhost 80 Trying ::1... Connected to localhost. Escape character is '^]'.
Then type in something like:
GET / HTTP/1.1 host: fuel18.test.local Accept-Encoding: gzip
so GET the url, enter the name of the virtual host, the accept header, en double enter after that to execute. You should see it returns a lot of garbage. If you do not add the accept header, you would see readable HTML (or json).
p.s. to make it clear, gzip encoding only works if the client sends a "Accept-Encoding: gzip" header.