Look closely at the video (below) ... you see the assailant on the left of the screen. He then prepares to hurl the pie -- which appears to be some sort of white foam in a foil pie dish. Murdoch's wife, Wendi Deng (pink jacket) ... hurls her body toward the man to block the attack.
The assailant -- real name Jonathan May-Bowles -- ended up getting the brunt of it.
Murdoch was in Parliament to testify about the News of the World scandal.