Where's the beef? Taco Bell sued for putting too little meat in its "meat"

At least not according to Beasley Allen, an Alabama-based law firm that has filed a class-action lawsuit against Taco Bell for misleading advertising. Its beef is the beef, or lack thereof: Allegedly, the taco filling has only 36 percent animal protein. And that, the lawyers claim, is not enough to tout the filling as "meat."

The rules here are a little tricky. The U.S. Department of Agriculture defines beef as "flesh of cattle," which is what makes up the 36 percent meat content of the tacos. Beasley Allen is insisting that Taco Bell use the words "taco meat filling" instead -- but given that the USDA definition for "taco meat filling" stipulates it contain at least 40 percent meat, that descriptor doesn't actually fit, either.

So what's actually in the taco filling? Stuff like "Isolated Oat Product," anti-dusting agent, autolyzed yeast extract and sodium phosphate.

Those delicious-sounding ingredients haven't stopped Taco Bell from insisting that it serves "high quality Mexican food," and vowing to fight the lawsuit vigorously.

The law firm is seeking an immediate halt to the advertising and a corrective educational campaign. Which means that at some point in the near future, the chain might be serving "taco meat filling tacos." Somehow, that just doesn't have the same ring.