(Reuters) — ABC News on Wednesday asked a federal court to throw out claims it defamed a meat processor through a series of television reports about lean finely textured beef, a product that critics have dubbed "pink slime."

In court papers, lawyers for the U.S. network said a September lawsuit by Beef Products Inc. seeks to inhibit free speech. They said the lawsuit poses a challenge to the right of a news organization "to explore matters of obvious public interest — what is in the food we eat and how that food is labeled."

BPI, based in South Dakota, is seeking $400 million in compensatory damages for lost profit it says was caused by the network's reports. The damages potentially could be tripled under a South Dakota law on disparagement of agricultural products. The company also is seeking punitive damages.

BPI is the nation's largest producer of lean finely textured beef, a product used in ground beef that is made from trimmings and on which ammonia is used to remove potential pathogens.

The ABC reports, which aired in March and April, raised questions about the quality of the product. A number of fast-food restaurants and retailers, including Wal-Mart Stores Inc. and Safeway Inc., stopped selling ground beef containing it, even though the U.S. Department of Agriculture and industry experts say the product is safe to eat.

Other defendants in the lawsuit include a former U.S. Department of Agriculture microbiologist credited with coining the term "pink slime" to describe the product in a 2002 email to colleagues later obtained by The New York Times.

ABC defended its use of that term in its reports.

"Pink slime is exactly the sort of 'loose, figurative, or hyperbolic language' that courts recognize demands protection under the First Amendment," the network's lawyers, from law firm Williams & Connolly, wrote in the court filing.

ABC, a unit of Walt Disney Co., filed its motion to dismiss in federal court in South Dakota.

A lawyer for BPI, Erik Connolly of the law firm Winston & Strawn, said the plaintiffs would oppose the dismissal motion.

"We believe the complaint sets forth valid claims," he said in an email.