McDonald's: Here's what a McRib is really made of

McDonald's (MCD) has lifted the curtain on the McRib, one of its most popular limited-time offerings, in a new video aimed at boosting transparency at the fast food giant.

As part of McDonald's ongoing effort to dispel myths about its food, the company invited a high school teacher who'd tweeted disparagingly about the sandwich to join Grant Imahara, former star of the TV show "MythBusters," to see what goes into the boneless barbecue pork sandwich.

"Someone sent me a picture of what I thought was a McRib, and I put 'Wow' with a bunch of Os and Ws, and that looked disgusting," said the teacher, Wes Bellamy, in the video. "And I was encouraging everyone to never eat anything from McDonald's again."

First, the pair check out the raw McRib meat-chunks of boneless pork picnic, which Imahara points out doesn't contain bones or gristle.

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After a visual inspection, the meat goes through the grinder before being formed into the shape of a rack of ribs. The patty, which contains pork, water, salt, dextrose and preservatives, is then misted with water to keep it from dehydrating during the freezing process.

"This is not like I thought it would be," Bellamy says of the production.

This isn't to say that Bellamy thinks his original tweet included an incorrect photo of the sandwich.

"[Y]ou know what it's kind of crazy because it's different now that I know what actually goes inside of it, and I know what actually the process is in terms of making it. It's actually good pork," he said.

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While Imahara's only comment about his first taste of the McRib is that it's "a lot messier than a lot of the other things," Bellamy sings the sandwich's praises.

"All of my questions have been answered," he said. "The sandwich is pretty good, man. It's actually really good."

McDonald's is banking on videos like these to emphasize the quality of its food and change its public perception, which has been impacted by uproar about its former inclusion of pink slime and a meat scandal earlier this year in China.

Sales also have been struggling at the fast food giant. During September, the company saw comparable sales drop sharply to the tune of 4.1 percent in the U.S.