Agree with post above ^; you need to run packing tape along the bottom seam.
I use a turkey-size (big) nylon bag for my quilt, and the large size (which should be called medium) for clothes, and a double medium bag for my food.
To close I twist the open end closed, make a loop of the twisted area, then bind across the double-thick twisted area with a NiteIze Gear Tie. This is now sturdy enough to use as a hang bag, and I DO use it as such. Just slip a carabiner in the twisted loop and haul it up.
The double bag I use for food storage is more durable, gives one more layer of protection against spills, *maybe* helps a bit with odor control, but the main advantage is: the area between the inner and outer bag becomes my clean "catch-all" area while cooking. Bandana, spoon, lid, lighter, whatever...it stays clean in between.