...they really are looking for your brains, but it appears that a thick gel formation made from gelatin, sorbitol, glycerin and some food coloring can be a good stand in. That's what movies are using to simulate good, thick, fleshy, body parts. If you have some stored in the fridge, you could toss them at the invaders as a decoy that would delay them enough to give you a few extra steps to make it too your car [*]. Best of all, all the ingredients are edible so you could even sit down with the zombies for a picnic if you think they are just poor, misunderstood creatures that just need some understanding.
[*] But of course, you will then discover that you can't escape because either a) you forgot to grab the keys, b) the zombies already pulled the wires to the spark plugs, or c) you're one of the 25 stereotypical characters that has to die in order for this to be a proper horror movie.