1. Introduction

Background Research

Questions Addressed
What is transglutaminase?
How does transglutaminase work?
Where does it come from?
Why is transglutaminase used for cooking?
How can it combat meat wastage?
Are there any negative side effects from using transglutaminase?
Is there any better alternative such as gelatin?

Literature Review
Transglutaminase, or meat glue, is widely used in modern cooking, usually in the form of powder. The powder is not pure transglutaminase though, as commercial products blend other ingredients such as gelatin, phosphates, caseinate, potassium chloride, fiber or maltodextrin to make it adequate for specific applications (Danny, 2013), (Kamozawa, Talbot, & Talbot, 2011). Activa® RM is the proprietary name for the protein adhesive. Transglutaminase is an enzyme that speeds up an irreversible reaction whereby a covalent bond forms between two functional groups, i.e., a free amine and an acyl, from the ends of the side chains of glutamine and lysine, both are amino acids. The covalent bonds formed are very stable. Hence, insoluble long chains of amino acids form more bonds, and pieces of meat stick together and look like an entire chunk of uncut meat.  

Transglutaminase is a naturally occurring enzyme that can be found in various animals, plants and in the human body. It plays a major role in the human body as it is a coagulant, clotting blood when needed and keeping skin firm. In mass-scale, it is produced through either the fermentation of a bacterium called Streptomyces mobaraensis or extraction of pig, cow or chicken blood that has transglutaminase-containing plasma (Kamozawa, Talbot, & Talbot, 2011) (Tseng, Liu, & Chen, 2002).

Transglutaminase is used only in 0.3 percent of all meat consumed in the United States of America (“Questions and answers about Transglutaminase (TG),” n.d.). However, this percentage may increase as people discover how to fully harness the ingenuity of transglutaminase. It allows us to gently manipulate the textures of meat, makes the dish unique, and allows butchers to stick meat together without strings or toothpicks. It can improve yields and presentations and creates new possibilities when working with dairy (Kamozawa, Talbot, & Talbot, 2011). Innovative individuals such as Wylie Dufresne has utilised transglutaminase to invent a pasta but the noodles are not made from wheat flour, instead it is 95 percent shrimp (Bonné, 2005).

Within optimal pH levels between 6 and 7 and temperature range between 50 degrees celsius and 55 degrees celsius, transglutaminase works best and the reaction of  meat sticking together will be quickened. Once exposed to air, oxidation of transglutaminase comes immediately into effect as there is moisture in the air. Therefore, any remainder should be vacuum sealed and kept in a refrigerator or freezer to increase shelf life (Kamozawa, Talbot, & Talbot, 2011). Getting the right ratio of meat to transglutaminase in charcuterie is also essential. If the weight of transglutaminase is below 0.05 percent of the weight of all meat used, the meat might not stick at all. If the weight of transglutaminase is above 2 percent of the weight of all meat used, the meat will be dry and have a tough texture, unsuitable for cooking (Danny, 2013).  

Obviously, cows, fish, chickens and pigs are not square-shaped animals that we can cut perfectly into cuboids and cubes; if that would be the case, a lot of meat will be saved. Unfortunately, 570 thousand tonnes of fresh meat are wasted in households each year, excluding industrial premises. This happens as meat come in shapes that are hard to cut to serve in equal proportions to customers. Thus, little to medium-sized pieces of meat are wasted and all these add up to 12 billion animal lives wasted (Hird, 2014). Fortunately, the growing use of transglutaminase will help to reduce the amount of animals’ lives that go to waste. As mentioned repeatedly, transglutaminase binds meat together, so meat that was destined to go to waste can now be stuck together to form entire large chunks of meat that can be shaped to cut evenly. This also saves the amount of crops grown to feed livestock, water used for livestock and vegetation, and money. Indirectly, our environment will also be less damaged because less coal and fossil fuels are burnt. The rate of the degradation of the earth’s ozone layer will gradually decrease, hopefully slowing down more than the repair of the earth’s ozone layer. Climate change will be less drastic too.

The FDA classifies transglutaminase as “generally regarded as safe” or GRAS for short and it is not an allergen as well (“Myth: ‘Glue’ is used to hold some meat together,” 2017). However, there has been a lot of controversy surrounding this catalyst. According to Schneider (2012), marketing consultants and food scientists estimate — because no company will discuss sales figures– that anywhere from 11 to 35 percent of all packaged and sliced ham, beef, chicken, fish, pizza toppings and other deli products are enhanced, restructured or molded using transglutaminase. Despite the fact that federal laws require labeling, Scripps Howard News Service spot-checked meat purveyors and restaurant suppliers and found that almost no companies listed the substances among their products’ ingredients (Schneider, 2012). This shows no consideration for people with religious and dietary beliefs and special needs. Selling cheap unwanted put-together meat as a high-end-appearing cut at a high price is also unethical. The above problems are irresponsibilities of companies and sellers. “Questions and answers about Transglutaminase (TG)” (n.d.) states that The US Department of Agriculture, i.e., USDA has approved the use of transglutaminase for use in meat and poultry products. Furthermore, the Food Safety and Inspection Service, i.e., FSIS has assured that it is safe for meat and poultry products developed to reduce total sodium and fat amounts in the ingredient list of the latter (“Questions and answers about Transglutaminase (TG),” n.d.). To date, transglutaminase has proven to be a safe way of combining meat products to meet the demands of our rising population (“Questions and answers about Transglutaminase (TG),” n.d.). Transglutaminase does not affect the allergenicity of proteins; it does not promote the contamination of meats, and it is thermally decomposed when the meat is thoroughly cooked reaching a safe internal temperature, which kills unwanted bacteria such as E.coli or Salmonella (“Questions and answers about Transglutaminase (TG),” n.d.). Transglutaminase is entirely denatured and ineffective at 75 degrees celsius (Kamozawa, Talbot, & Talbot, 2011). Hence one should not be worried of consuming any transglutaminase when eating the meat. On the other hand, “39” says that the dangers of transglutaminase is that the bacteria is hard to track because different meats from different animals are glued together. This makes it harder to diagnose where the disease comes from in case an outbreak of bacteria happens. Furthermore, the bacteria that is originally outside of separate meats are glued together so the bacteria will be hidden inside the meat between the glued meat pieces. This is extremely dangerous because for the heat to reach the insides of the meat to kill the bacteria, the meat will be burnt and people will not like it. Therefore the meat is sometimes not cooked properly and the bacteria inside would not be killed and that would cause food poisoning, dire illness or death in serious cases. Moreover if transglutaminase is not cooked properly, the extra transglutaminase in the body would be associated with plagues in the brain of the Alzheimer’s, Parkinson’s, and Huntington’s Disease, Cataracts in the eyes, the hardening of the artillery and various skin disorders. Lastly if the meat glue is ingested, the body’s immune system will classify its own transglutaminase as foreign as well and will lead to gluten allergy and Celiac Disease. (39, 2016)

However since transglutaminase is not readily available in Singapore, we searched for a suitable replacement for transglutaminase and we found gelatin.

Gelatin is a mixture of peptides and proteins produced by partial hydrolysis of collagen extracted from the skin, bones, and connective tissues of animals such as domesticated cattle, chicken, pigs, and fish. During hydrolysis, the natural molecular bonds between individual collagen strands are broken down into a form that rearranges more easily. Its chemical composition is, in many respects, closely similar to that of its parent collagen. (Schwenke, 1978) Gelatin is also readily available throughout the globe. With the production of 375,000 to 400,000 tonnes a year they are more easy to obtain compared to transglutaminase.

According to Theresa J. Marquez (2015), gelatin can be used for the making of meatballs. She said that gelatin can be used to make a denser meat ball hence chewier. This means that gelatin acts like transglutaminase on meat too, binding the fibres of muscle together. Another source also suggests that gelatin not only binds the meat together, it offsets the need to use gluten-filled starchy binders which is a healthier choice. Furthermore according to J. KENJI LÓPEZ-ALT he says that gelatin can replace veal because veal makes the meat loaf bland but yet gelatin can bind the fibres of meat together and make the meatloaf tender and moist without diluting the taste. (ALT, 2015)

Froning (1965) said that there was a significant improvement in the tear strength of chicken meat when it is soaked in 6% polyphosphate solution. Direct addition of polyphosphates (0-2%) and of dried milk solids (0-10%) and gelatin (0-6%) significantly increased the tissue binding ability as the amount of each binder increased. (Froning, 1966) Gluten flour (0-6%) also increased binding but the increase is not significant. (Acton, 1972)

Activa GT (greatest bond) is a mixture of transglutaminase, maltodextrin, gelatin and an anti caking agent. They also stated that gelatin bonds extremely well with gelatin thus Activa GT form strong bonds. Therefore this shows the connection between gelatin and transglutaminase, literally and figuratively, and we will find out if gelatin can also bond meat. (Wise, 2006)

The Prior Art One process comprises the deboning of a ham and then the cutting of it to form two integrally connected sections. Gelatin is spread on the cut surfaces which are then pressed into contact with each other where upon the ham is compressed and cooked in a mold. However this process leaves much to be desired because the meat pieces are not firmly bonded together but tend to pull apart when the molded composite is sliced; also the gelatin changes the natural flavor of the meat, and the process is expensive. The tenderizing of pieces of meat by puncturing or slitting of the surfaces of the pieces is also known, and it is known to pimpuncture stacked pieces of meat and then to mold the composite assembly to the desired shape while the assembly is being chilled. However, the pieces are not firmly bonded together even when, as in most instances, the pieces are coated with gelatin.

Since there is not much research done about gelatin bonding meat, only gelatin suspending meat. We will do this experiment to see whether gelatin can also bond meat as gelatin is a cheaper alternative compared to transglutaminase.

Research Questions 

  • What is the relationship of mass of gelatin in fish ball to the rebound height of fish ball when dropped on smooth surface parallel to ground?

  • Why is the relationship such?

  • How can we make use of this relationship to better the making of fishball and other foods?


We hypothesise that the more gelatin added to the fish paste, the higher the rebound height of the fishball will be until a certain point where the more gelatin added to the fish paste, the fishball will decrease in rebound height. We believe so because there will certainly be a point at which the total weight of the fish ball is a stronger force than the force required to break the binding of gelatin. Hence, that limit prevents the fish ball from continuously increasing in rebound height while the gelatin content of the fish ball increases. Therefore, there will also be a point where the rebound height is zero because the fishball covered in gelatin splatters upon impact with the wooden surface.


  1. Catalyzes acyl transfer reactions from glutamine residues in proteins or peptides to primary amines, e. g. the formation of ε-(γ-glutamyl) lysine bonds between proteins by transferring the acyl group of a peptide-bound glutamine residue to the primary amino group of a peptide-bound lysine residue. transglutaminase