Kids eat paste. Why worry about meat glue?

You may have recently seen something on the internet, social media, or the news about something called ‘meat glue.’ What the heck is that?

 

 What the media refers to as ‘meat glue,’ is known in the meat industry as transglutaminase (TG) or beef fibrin. They are enzymes used to bind proteins together. Enzymes are proteins that cause chemical reactions to happen in living things. There are several types of proteins in the body, proteins that hold things together (think tendons), proteins that make things move (muscle), proteins that break down food to produce energy (some of these are enzymes), proteins than break down other proteins (some of these are enzymes used as meat tenderizers), and proteins that help build other proteins to help them function correctly.

 

TG and fibrin fall into the last category. They help to build other proteins. They cause proteins in muscle to bind with one another to form a strong bond. So in meat, they can help bind two pieces of meat together.

 

Why is it used in the meat industry?




Beef tenderloin

 Muscles are all kinds of crazy shapes. Some are huge, some are long and skinny, some are shaped like triangles or trapezoids or who knows what. It is hard for butchers to take those muscles with all those different shapes and form them into cuts of meat that are the size and shape that people want to eat. For example, the tenderloin is the most tender muscle in the body and is used to make filet mignon. It is about as big around as a base ball at one end and tapers down to a point at the other. On one end, butchers can cut nice pretty round steaks, but as they cut more and more steaks, they get smaller and smaller. As the butcher gets closer and closer to the small end, the pieces are too small to make a nice steak. They are still the most tender muscle in the body, but they won’t make pretty, portion sized steaks. So, meat scientists and chefs use TG or fibrin to stick two tenderloins together with the skinny end of one adhered to the fatter end of the other one and visa versa. It is still tenderloin, still the most tender cut in the body, but with TG, butchers can cut more, pretty round steaks. More meat for everybody!

Sometimes, chefs use TG or fibrin to get the bacon to stick to filet mignon. I’ve seen examples of it used on salmon and to make that imitation crab stuff.

 

 Where is it found?

 

If these ingredients are used in a food that you buy at the store, according to USDA, the food must be labeled ‘formed’ or ‘fabricated’ or ‘shaped’, as in ‘Formed Chicken Breast’ or ‘Fabricated Steaks.’ A meat product containing TG or fibrin will also have an “enzyme” to transglutaminase enzyme” in the ingredient list. When you cook them, you should treat them like ground meat and cook them to at least 160°F for red meat and all chicken should be cooked to 165°F.  

 

Of course, you can’t read ingredient statements when you dine at restaurants. You can always ask. Foods that are prepared prior to coming to the restaurant will have TG on their ingredient list, and a chef will be able to tell you if he or she is using it themselves. They should be trained in preparing foods containing TG safely, so it should be cooked to safe temperatures.

Some people are concerned that TG or fibrin are going to be used to turn cheap cuts of meat into cuts that can be sold at a higher price. Cheap cuts of meat are cheap for a reason; nothing can change the texture or flavor to make them like filet mignon. If a chef or a company were doing something like that, not only would it hurt their business, it would be against the law. The USDA dictates labeling laws on cuts of meat, and only tenderloin can be labeled as ‘tenderloin’. The folks at the American Meat Institute stated that they do not have any evidence that these deceptive practices are happening.

Furthermore, TG is too expensive to be used on cheap cuts of meat. Because of its price, you will only see it used on expensive cuts like tenderloin or salmon patties or in high-end restaurants where chefs demand higher prices. So, you’re not really consuming it very often. AMI estimates that about 8 million pounds of meat containing these products are sold annually, that is out of 49 billion pounds of beef and pork sold each year (0.016%).

 

As a meat scientist, I think that TG and enzymes like it are neat and exciting. I think it is fun to see what chefs and the guys and girls in research and development come up with using them. I don’t feel like we are trying to trick anyone. And, I know to cook these products to 160°F.

 

Here are some other good sources on transglutaminase and fibrin.

• This video is the best I’ve seen explaining the process and showing how TG is used.
• In this Meat Myth Crusher video, my friend Dr. Dana Hanson, from North Carolina State University explains how TG is used.
• This is a blog post about meat glue from culinary blog called Cooking Issues.
• This is a statement about binding enzymes used in meat products from the American Meat Institute.

A fourth case of mad cow disease and still the safest food supply in the world.

As you may already know, a dairy cow in California was diagnosed with Bovine Spongiform Encephalopathy (BSE), commonly known as Mad Cow Disease. The 10 year old cow died at an undisclosed dairy farm, and the disease was found when her body was sent to a rendering facility. Here is the official release from USDA.

Why am I not worried about this?

First, the cow was not destined for our food supply. She was at a rendering facility. These are companies that dispose of dead animals and produce inedible products. There is a testing system set in place by USDA to test the bodies of a certain number of the cows for BSE before they go through their process.

What about the milk she produced? BSE is not transmitted through milk.

I heard on the radio last week that her offspring are going to be euthanized to keep them out of the food supply, too.

What about the rest of the beef supply? BSE is not transmitted through meat, either. However, BSE is found in the nervous system. The USDA has very stringent rules in place to keep BSE out of our food supply.

What are those safeguards?

The molecule that causes BSE is only found in a few places in the body including the nervous system, small intestine, and tonsils. The small intestines and tonsils of all beef cattle are no longer used in the food supply. Also, BSE is much, much more prevalent in older animals. The USDA requires that beef processors look at the teeth of every animal slaughtered to determine how old they are. If they are older than 30 months, then the spinal cord, brain, eyes, and any parts that may contain nervous tissue are also removed from the food supply. They refer to those parts as Specified Risk Materials.

Cows that have BSE have a very hard time walking and eventually get where they can’t move on their own. We refer to those cows that cannot get up on their own as ‘down(ers)’ or non-ambulatory. Down cows are far more likely to have BSE, and when cows are down, veterinarians cannot observe the signs of BSE. Therefore, if a cow is down and cannot get up, then she may not be harvested for human food.

Also, BSE was previously transferred from cow to cow because meat and bone meal from cattle and sheep was fed to other cows as a protein source. The US (FDA) banned that practice in the 1997. So, we shouldn’t be spreading the disease anymore.

Are the safeguards working?

Yep. Like a charm. This was only the 4th case in the US ever and last year there were only 29 cases worldwide. In 1992, there were over 37,000 cases.

Although some people were sickened in Britain in the 1980’s and 1990’s, no one in the US has been known to have been sickened from eating beef from BSE infected cows.

How do cows get BSE?

BSE is an infectious disease that is transferred from animal to animal in a rather unique way. The infectious agent of BSE is a protein called a prion (pronounced pree-on). All animals have prions. Prions, like all proteins, long chains that are folded up in a specific way. In healthy animals, the prions are folded into several helical shapes (kind of like a slinky gone wrong). Scientists call them alpha-helices.

  In animals with BSE, the prions have refolded and the helical shapes have changed to flat, sheet structures, called beta-sheets. These beta-sheets allow the prions to stick together and form plaques. Those plaques cause changes in brain function and make the animal sick.

What is weird about BSE is that, when these bad prions are introduced to the body, the bad prions teach the good prions how to be bad. Somehow, they cause the healthy prions to refold themselves. Maybe we should call them zombie prions.

So, when a bad (zombie) prion is introduced, it takes a while, but it can teach all the healthy prions to refold. How are bad prions introduced?

 1. Well, sometimes the prions just sporadically decide to change. That is really rare. But, when it happens, the animal will slowly form more and more bad prions until it becomes ill.

2. Sometimes it is genetic. The bad prions are passed from parents to offspring.

The dairy cow in California has been found to have atypical BSE, which means she developed BSE in one of the above ways.

3. BSE used to be passed between cows through feed. When animals are slaughtered, not every part can be eaten by humans. Some parts and pieces are converted to a product called meat and bone meal. Farmers used to feed meat and bone meal back to other cows as a source of protein. Bad prions were being spread that way in Britain in the 1980’s and 1990’s. When scientists realized that was happening, this practice was banned. So, the cow should not have gotten BSE that way.

What about other animals?

Cattle are obviously not the only animals that get this type of disease. Humans have similar diseases caused by bad prions known as Creutzfeldt-Jakob disease, Kuru (found in native people in New Guinea who practiced ritualistic canabalism), Gerstmann-Straussler-Scheinker disease, and Fatal Familial Insomnia. The bad prions in humans come from similar sources as cows; including genetic, sporadic, and from food (meat containg nervous tissue from cattle with BSE). Some people have gotten the disease through neurosurgery or eye implants.

Scientists think BSE in cattle may have originated from a disease in sheep called scrapie. Meat and bone meal from sheep fed to cattle contained bad sheep prions.

Deer and elk also get a disease called Chronic Wasting Disease. Big cats and exotic ungalates (antelopes etc.) contracted forms of spongiform encephalopathies during the height of the BSE epidemic in Europe.

The safegaurds in place to protect humans are also protecting these other species.

There are lots of websites with information about BSE.

My friend Ryan Goodman at I am agriculture proud has compiled several sites.

There is a new website called BSEinfo.org. Several of my links will take you there.

If you have any questions or concerns, please feel to comment.