[Symbiote]

The question is wrong, as it stands the answer is "any non-fluid or contained fluid that will fit".

"What should one store in a refrigerator?" is a better question.

[marvy]

Yeah. He was really trying to answer the 'should' question.

[downer70]

One could also refrigerate contained gases.

[thaumasiotes]

As your parent comment explicitly stated. Gases are fluids.

[i736680]

I would argue that pretty much anything you would put into your refrigerator is contained inside packaging. Sometimes that packaging is just a simple plate.

[TeMPOraL]

I put a cat in the refrigerator more than once - for some reason, my cats loved sitting there for few mintues long when there were young. There were definitely not packaged.

[cdcarter]

I put a lot of fruit and vegetables in my fridge with no packaging. Why would I contain them?

[zombees]

While arguably not correct, is there any particular reason to downvote this? I think it's a fairly valid point