Meat glue: it's what's for dinner!
It may well be, as meat glue--transglutaminase--is used to make fake steak, sausage and hot dogs, imitation crab, fish balls, and, I suspect (but don't know for sure) chicken nuggets.
TG is an enzyme that catalyzes covalent bonds between free amine groups in a protein, like lysine, and gamma-caroxminid groups, like glutamine. These bonds are pretty durable and resist degradation once the food has been formed.
In other words, it's a very strong glue. The enzyme comes from pig or cow blood, but if it's in your food, you probably won't know it, as there is no labeling requirement. If it's on the label at all, it will be as "composite meat product," so you might want to read those labels.
Watch the video to get an idea of how it works. For a "steak," say, you sprinkle the meat glue over chunks of meat, roll them up tightly in plastic wrap, and refrigerate overnight. In the morning, you've got a roll of meat that can be sliced into filet mignon-type "steaks." Notice, in the video, that the butcher and the reporter wear masks as the TG is sprinkled onto the meat. That's because they don't want to risk thrombosis.
Meat glue has recently been approved by the EU. Plenty of consumers are outraged by the decision, which reverses the EU's previous stance.
Many people, however, not only have no problem with TG, but wholeheartedly embrace it. Nils Noren and Dave Arnold, who author the high-tech food blog Cooking Issues, are enthusiastic about it. Innovative, avant-garde chefs experiment with it, producing such things as pasta made almost entirely out of shrimp. With meat glue, you can take different types of fish and meld them together for a new kind of fillet, or different kinds of meat for a "mixed grill."
Over at BoingBoing, Maggie Koerth-Baker and her commenters wax enthusiastic about the stuff. Commenters have used it to make turkey confit and to glue bacon and scallops together. Also coming in for praise on the blog is the idea of not wasting any meat--making what was previously un-sellable attractive and sellable.
After all, humans have long used meat scraps and the less aesthetically appealing parts of the animal in head cheese, blood sausage (black pudding), and the like. Someone on BoingBoing mentioned how native Americans used every part of the buffalo.
I can see the point, but unless I have a guarantee that the meat comes from grass-fed beef without antibiotics or hormones, I myself would rather not eat certain scraps. Organ meats in CAFO animals are notorious for their concentrated toxins.
Also, there is a much higher risk of food poisoning with "steaks" made with meat glue. As microbiologist Glenn Pener points out in the video linked above, “The amount of bacteria on a steak that’s been put together with meat glue is hundreds of time higher.” Why? Because scraps of meat put together feature bits that were on the outside--where bacteria can gather--but now have surfaces on the inside, where it's hard to get rid of them through cooking. Think about grilling a real steak. Bacteria on the outside will be killed by cooking, but if you're eating your steak somewhat on the rare side, that inner meat doesn't cook as much. Which is fine, because (especially after dry-aging) the inside of the meat is a lot safer. But a patched-together "steak" has lots of exterior (think beef stew meat) that becomes interior. Those previously exterior pieces are hard to cook thoroughly. For this reason, restructured steak should, according to the Wiki entry, always be cooked well-done. I doubt that it always is, though.
And finally, consumers should feel insulted by the deception going on. Inferior meats can be sold as if they were premium cuts: good for profits. Along with such things as surimi and restructured steak, one of the uses for meat glue listed in the Wiki entry is
(Before leaving the uses for transglutaminase, I should point out that "meat glue" is something of a misnomer, as TG is also sometimes used in noodles and in milk and yogurt.)
I really resent the deception employed by the meat industry. There's no end to it: gas-injected packaging to keep meat red; water injection to make it plumper, heavier (pay by the pound, remember?), and better looking; pink slime in ground beef; and now I learn about meat glue.
I also tend toward plain cooking (Mark Bittman is my hero) with natural ingredients, and meat glue doesn't fit into my food philosophy at all. But hey, if meat glue sounds like something you'd like to try in your own kitchen, you can buy some through Amazon!