Beef Products Inc., maker of the ground beef filler USDA scientists nicknamed "pink slime," plans to launch a consumer education program aimed to restore confidence in the product it calls lean finely textured beef and the process it uses to sanitize and separate beef from meat scraps formerly used in pet food and cooking oil.
"'Pink slime' doesn't exist," Jeff Carlson of BPI said. "'Pink slime' never existed in any way, shape or form. Our product is 100 percent beef in every regard, from quality to nutrition."
The company held a news conference to say it will remind consumers that the USDA has given its seal of approval to the meat that was in 70 percent of grocery store hamburger until many of the nation's largest grocery stores, responding to consumer concern, removed it from their shelves.
BPI said the product is as "safe and as nutritious as ground beef."
"It has the same nutritional value as any 94-percent lean product that you'd find on the marketplace today," Carlson said.
Critics say BPI, which has won food safety awards for its ammoniating process, overstates the product's similarity to fresh ground beef, because of the process it goes through to separate the meat from the fat and to kill bacteria.
Gerald Zirnstein, the former USDA microbiologist who first used the term "pink slime" and recommended against its inclusion in ground beef, said the first problem is that the BPI process begins with warming the meat scraps just enough so they don't cook but are easier to separate in a centrifuge.
"At that temperature, you increase the level of pathogens and the level of spoilage bacteria," Zirnstein told ABC News. "In order to turn this into a product they can potentially sell as 'meat,' and that's, [in] quotations, 'meat,' they add ammonia."
"Ammonia does two things most people don't realize," Zirnstein said. "In high levels, it does more than just kill the ... pathogens. It also fixes the color of the meat. So the red meat stays pink."
Zirnstein said that is why he coined the phrase, "pink slime."
"If that ammonia wasn't there, if it wasn't added to kill the bacteria, it would also come in as a gray product and you'd have gray slime," he said. "Gray slime!"
The former USDA scientist said that's his main complaint and the reason he recommended against the product's use.
"Because the ammonia fixes the color into a pink color, it can, quote, 'pass' as red meat, but it's a low-quality product going into the ground beef. The public's not aware of it, hasn't been for years. It's not their fault. Nobody told them."
BPI said lean finely textured beef is not labeled because it's just ground beef, and the company objects to it being called an additive.
Zirnstein said it is more than an additive. He calls it "an adulterant."
Company Fights Back
A former high-ranking BPI executive -- who the company said was fired and is now disgruntled -- disputed BPI's claim that its raw material, the beef trim, is the same as any other scraps used to make ground beef.
"Pink slime," said Kit Foshee, "comes from cuts or fat that is most-highly susceptible to contamination during [the] slaughter process. Removing hide ... that's exactly where the fat is harvested from ... when they centrifuge, they're going to concentrate harmful bacteria."
And it was those extra pathogens that led BPI to use ammonia gas to kill the bacteria.
Zirnstein's former colleague at the USDA, Carl Custer, also a retired microbiologist, said the claim that "pink slime" is as nutritious as ground beef is wrong.
"Microbiologically safe and nutritionally complete are two different issues," Custer said. "It may be pink [but], nutritionally, it is not equivalent to whole-muscle tissue."
Custer said the ammonia gas does kill E. coli and salmonella if done properly, but much of the protein in lean finely textured beef is different than protein in pure ground beef.
"It would be sort of the equivalent to something like Jell-O or gelatin" said Custer. "Gelatin is connective tissue. It's been boiled down, but it is a protein. It's just not a complete protein. Add sugar to it and other things and it's delicious. And you do get some nutritional value. It's not as nutritional as whole muscle meat."
"Pink slime" does provide nutrition, but not as much as ground beef, according to Richard Ludescher, a nutritionist at Rutgers University in New Jersey who, at the request of ABC News, reviewed data from a study on lean finely textured beef from Iowa State University.
Ludescher said that because lean finely textured beef has five times the collagen level as standard ground beef it "will have a lower nutritional value than beef muscle."
Collagen is a protein, he said, that is higher in non-essential amino acids and lower in essential amino acids than meat from an animal's muscle.
"Addition of LFTB would thus lower the nutritional quality of ground beef," Ludescher said.
He added that even though it is not as nutritious as ground beef, Americans eat much more protein than we need so eating lean finely textured beef would not impact the average American's diet.
"The effect is certainly inconsequential," he said.
While BPI attempts to make its case to a public clearly concerned about what is in their ground beef, Bettina Siegel, a Houston mother of two who launched the change.org petition to ban the product from school lunches, continues her fight to "just label it."
BPI's vice-president and the wife of the owner responded in her press conference Monday: "What should we label it? It's 100 percent beef. What do you want us to label it?