Most of our sous vide food is first frozen in vacuum sealed bags. We have had three-year-old food that was sealed and frozen and it was just as fresh as when it went into the bag.
External vacuum sealers like Weston's work well; cheapos like Food Saver can work but getting consistently good seals is more difficult. Recently we have gone to a chamber vacuum sealer, something my BIL would call "rubber tire living."
Keep foods fresh, store leftovers, marinate, or seal for sous vide with this America's Test Kitchen top pick in compact vacuum sealers (August 2014).
westonbrands.com
Powerful, space-saving chamber vacuum sealer for meats, marinades & sous vide. The USV20 includes BPA-free pouches, hose & adjustable vacuum control.
avidarmor.com