The McRib sandwich, which officially completed its latest appearance at McDonald’s stores nationwide yesterday, is giving customers more than just a longing for one more tangy taste experience. Its disappearance is accompanied by a revelation that might leave even some of its most ardent admirers with a bad aftertaste.

For participants in the pork industry, the sandwich is a concoction that symbolizes sheer genius, not to mention the movement of thousands of tons of product. For people not cashing paychecks from meat companies, however, the McRib is either disgusting and inedible or an object of love and devotion, as you wait patiently for its periodic return to your local McDonald’s store.

Not much in between.

Indeed, the fast-food chain’s most recent ad campaign, in which a hapless new bridegroom debates whether to head off to his honeymoon or stick around for the McRib promotion, not-so-subtly reinforces exactly that kind of (some would say irrational) affection.

Such affection’s not limited to ad-inspired characters, either. As Nick Carbone wrote in TIME magazine’s “Trending Now” column last month, “Upon hearing that McDonald’s was bringing the elusive, coveted McRib to all locations until November 14th, a quick glance at my watch told me this was an opportunity slipping away. I needed to grab hold of its golden, fluffy bun containing that paradoxically boneless rib-like patty.”

It’s that fluffy bun that’s suddenly causing problems, however, and the latest post in TIME’s Healthland blog is putting McRib under a spotlight.

And I don’t mean those lamps you see on a restaurant countertop.

Counting up the chemicals

The TIME article identified 70 different ingredients used in formulating McRib, including ammonium sulfate ( a GRAS additive used to activate yeast), polysorbate 80 (an emulsifier) and azodicarbonamide. That last ingredient—azodicarbonamide (ADA)—is a flour-bleaching agent that not only bleaches flour by oxidizing carotene (a pigmented compound that contributes a yellowish-orange color to plants) but also improves gas retention in the dough and thus the elasticity of the final product.

You like your burger (and McRib) buns to be light and chewy, rather than heavy and “doughy?” That’s why they add ADA, which by the way, is generally added at levels not exceeding 4.5 g per 100 kg of flour, or less than five one-thousandths of a percent addition.

Here’s the problem: Like many chemical additives used in food processing, ADA has other commercial uses, in this case the manufacturing of foamed plastics like those used in gym mats and the soles of athletic shoes. Which means that news coverage defaults to such as headlines as, “McFoam? McRib found to contain same ingredient as gym mat” (Fox News) or, “What’s the McRib made of, anyway? Find out if you dare” (The Week magazine) or, “The McRib Sandwich and a Yoga Mat: What Do They Have In Common?” (San Francisco Chronicle).

Even though you’d eventually find out that ADA is used in minute quantities—if you continue reading long enough—the scare story section always comes first. In all of the coverage, ADA is described as a compound that is banned as a food additive in Europe and Australia, although its use is permitted by the Food and Drug Administration. In Great Britain, that nation’s Health and Safety Executive has identified azodicarbonamide as a potential trigger for asthma attacks and requires that products using ADA must be labeled, “May cause sensitisation (sic) by inhalation.”

The TIME blog post also helpfully noted that there are 70 other ingredients found in a McRib sandwich, all of which exist in minute quantities and will almost certainly leave even the most devoted consumer of the sandwich unharmed.

If you get past the headlines, that is.

For the record, TIME’s Carbone ranked his McRib culinary experience as follows: “The bun: delicious. Warm and soft, a good consistency. The barbeque sauce: sweet but tangy. I could probably drink a gallon of it. The meat patty: tender but mushy, squishy, and basically unrecognizable.”

Ouch.

That’s painful for anyone in the meat business, but no more so than news coverage implying that the rib portion of the sandwich is what might taste like a gym mat.

That’s really distasteful.

The opinions expressed in this commentary are solely those of Dan Murphy, who is a veteran food-industry journalist and commentator.