Long story short, a friend of mine moved to a new place next to a really really old Jewish cemetery - so that got us thinking, if the zombie apocalypse were to happen, are brains kosher? Inquiring minds need to know...I'm no kosher expert, but a few decades of eschewing the swine have prepped me with a little background knowledge. Not to mention thoroughly geeking out with random books of Jewish law.
So here's the deal.
You can actually eat the brains of a kosher animal. Well, some kosher animals. My mother-in-law (who, I should note, is a native Australian) LOVES cracking open fish skulls & sucking the brains out. (I'm a vegetarian & i think she does it to psyche me out. It doesn't work.)
But that's not what you want to know. If you want to know about zombies, you want to know about REAL HUMAN BRAINS. Well, humans -- or any part thereof -- is not permissible to eat, regardless of whether you're talking about kosher-keeping humans or non. (You really wish that whoever started the blood libel rumors had Google access to give them a clue.) In order for any animal to be kosher, it has to have cloven hooves and chew its cud. So basically, if you're a kosher zombie, you are screwed.
One additional consideration: Kosher vampires are screwed as well. In the process of making meat kosher, the animal's body has to be completely drained of blood. So you know how, on Buffy, when Angel and Spike became good guys (or impotent), they had to drink the blood of animals? (Just kidding. You don't actually need to know that.)* Animal blood is out, too. I suppose there's a case to be made that, when a life is at stake,** Jewish laws such as kashrut don't apply. Then again, zombies and vampires aren't technically alive, are they?
If you're curious for more, you should probably check out Are Dragons Kosher?
* -- I believe a similar thing happened in Twilight, but I've mostly blacked it out.
** -- Notice how I avoided a pun about stakes? Joss Whedon is rolling over in his grave.***
***-- Apologies. I know Joss Whedon is not dead.