Google has improved its voice recognition controls in Android 4.1 Jellybean which let you allow to download voice recognition data for offline use of voice recognition services including voice typing, voice search etc. even when you have no access to internet.
Download Voice Recognition Data on Google Nexus 7
On your Nexus 7 go to “Settings” > Language & input”
In Speech section tap on “Voice Search” > “Download offline speech recognition”
You will find “INSTALLED” and “ALL” tabs to select a language to download voice recognition data, and as you make your language choice Voice Recognition Data download will start and thats it