I will go ahead and say that I -think- that this particular image was photographed that way - some of the tiny details reflected would be impossible to achieve without painting them on.
Moreover you don't have a clear horizon line in there, which would be rather hard to achieve in Photoshop to copy a mirrored image of. Not impossible, but hard.
I'll try to demonstrate on a quickie...
Image 1 (courtesy of http://usa.stockfood.com
) is an original and I believe it's similarly done. Image 2 is a Photoshoped reflection. And while it's rather lame, I just wanted to show that the reflection is about perspective - you see that the shadowed area of the garlic head seems bigger on the first image and it's correct. It's
the vertical vanishing point, closer to the viewer, and so it ought to. Likewise mind the wrinkle on the front - how on the original it looks "higher" than the Photoshoped one and how the head is reclining on the original.
So yes, my guess they are staged, but it doesn't necessarily have to be super-expensive studio shot. I think
that if you get creative with a black velvet, very soft light, mirror, lower ISO, different angles and long shutter, you may be able to achieve the effect.
Not a pro, though.
1 - this happens when I try to go about it technically and explain things.