How do I remove all materials (textures) from an object in Maya?

[martinluthar]

I want to delete materials from the entire scene. All objects.

If I could reset all materials to default (and be left with Lambert1, that would be fine)

I've been using 3ds Max for years and know how to easily reset the material palette, but can't seem to find it in Maya.

[guest84672]

Is this in preparation for export into KeyShot? Why not do this inside KeyShot by assigning a diffuse material at the top level? Simply drag and drop a material from the material library into the scene tree.