Red Slime: Scourge of Supermarket Sushi

You’ve heard of pink slime, aka ​“lean finely textured beef,” a bubblegum-colored paste made from the scrapings off cattle carcasses. But what about red slime, the viscous scrapings from the skeletons of tuna and other fish, a supermarket sushi staple, and sometimes a vector for food poisoning? As nasty as it looks, pink slime is treated with ammonia to kill bacteria and served cooked. Red slime is untreated and served raw.

The brilliant nutrition scientist Marion Nestle answers a reader’s questions about red slime in her montly Q&A column:

Q: I had no idea that the tuna in my sushi roll was scraped off the bones in India, ground up, frozen, and shipped to California. Is this another ​“slime” product? Can I eat it raw?

A: No sooner did the furor over lean, finely textured beef (a.k.a. ​“pink slime”) die down than we have another one over sushi tuna. On April 13, the Food and Drug Administration said Moon Marine USA, an importing company based in Cupertino, was voluntarily recalling 30 tons of frozen raw ground yellowfin tuna, packaged as Nakaochi scrape.

Centers for Disease Control and Prevention investigations linked consumption of Nakaochi scrape sushi to about 250 diagnosed cases and an estimated 6,000 or so undiagnosed cases of illness caused by two rare strains of salmonella. Among the victims who were interviewed, more than 80 percent said they ate spicy tuna sushi rolls purchased in grocery stores or restaurants. [Emphasis added.]

Nestle doesn’t call it red slime, but I’ve eaten enough sketchy sushi to recognize the stuff. My advice? Steer clear of chopped and ​“spicy” rolls, unless you watch the chef chop the fish.