“Meat glue” is transglutaminase, an enzyme in powder form, derived from beef and pork blood plasma. See the Wikipedia description of it here. Chefs most commonly use the Activa RM brand, which is transglutaminase mixed with maltodextrine and sodium caseinate, a milk protein. Using enzymes in food isn’t a new technique. Papaya seed is the main ingredient in meat tenderizers, for example. Rennet and yeasts produce enzymes that make cheese and alcohol, too. Natural enzymes. Meat glue is a darker product altogether.
Yet according to Cooking Issues, the French Culinary Institute’s blog (USA), meat glue is safe. That is, the major study carried out to gain acceptance by the FDA says so. And why shouldn’t we believe? It was funded by Ajinomoto, the product’s manufacturer, after all.
This video from Australia’s TodayTonight TV show demonstrates how easily you can create Frankenstein meat. Just sprinkle a teaspoon of powdered transglutaminase on various meat scraps, knead them together and roll them up in plastic wrap. Put in the fridge and 6 hours later, you have an easily-sliced piece of meat that looks like real fillet.
Only make sure to wear your face mask while performing the simple operation: you don’t want to be inhaling powder that makes your blood clot abnormally.