I usually fly only with carry-on luggage. However, on my next trip to Europe there are a bunch of things (mainly food) that I want to bring home (all legal food.)

I was thinking of stuffing a nylon duffel-style bag in my carry-on to then expand and sue for the way back - but I don't think that would be solid enough to be checked luggage on the way back.

Any suggestions as to a collapsible bag that has sufficient structural integrity to be checked?