New idea, under shed storage

[Bonnox]

Just thought I'd share my latest idea, I'm currently making a shed in my back garden, I managed to get some 2ft square concrete slabs that I was going to lay as my base, but then I had a thought these are thick slabs approx 3 inch thick, so.... I started to dig, so currently I have dug three holes then used the slabs and made the 3 holes into concrete lined mini bunkers with a slab on top so you can't even tell their there, I then plan to build the shed on top with trap doors in the base so I can access the hidey holes, I reckon they should get quite cool in there, when its all done ill take the temp over a few days and let you know, but, do you guys think it would be good for storing food and if so how should I store the food in them ?