|MadSci Network: Agricultural Sciences|
This is a challenging, unusual question. I don't believe that much research would have been done on this issue. My thoughts on a possible answer are that the canned would produce the least amount of gas -- the main reason being that it is the least contaminated with microorganisms that might add to the normal gas production during the breakdown of the food. But whether this is actually significant or not would be difficult to determine experimentally and probably would not be worth it. Hope that gives you a way to think about the problem.
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