 The so-called meat glue enzyme transglutaminase is used by the industry to add value by gluing together smaller scraps into a larger chunk. And not just to make fake steak, the American Meat Institute estimates it's used about 8 million pounds of meat every year in the United States. It can be used to cross-link pieces of any type of meat, fish, or meat product, hence can be used to produce large chunks of virtually intact-looking meat or fish out of small meat or fish cuttings. In fact, when these researchers actually tested for it in 20 samples of meat from the supermarket, they only found meat glue in salmon and turkey. I mean, how else are you going to get an improvement in gelling properties of minced lizardfish? Where does meat glue come from? For decades, the sole commercial source of transglutaminase was from the livers of guinea pigs. Now it can be sourced much cheaper, however the future of meat glue remains uncertain, because of, as meat scientists describe, communication difficulties. One of the reasons the industry is so excited about this stuff is because using meat glue enzymes, restructured meat can be made from underutilized portions of the carcasses. For example, you can get away with adding up to 5% tendons, and some people can't even tell the difference. This has raised food safety concerns, though. There's a risk that otherwise discarded leftovers of questionable microbial quality could find their way into the reconstituted meat. You can actually take a microscope and see introduced E. coli 015787 along the glue lines where meat pieces were enzymatically attached, which shows that the restructuring process can translocate fecal matter surface contamination into the interior of the meat. Furthermore, people who have problems with gluten may develop problems when ingesting meat treated with the meat glue enzyme since it functions as an autoantigen capable of inducing an autoimmune reaction.