Meet the Meat Makers

AnnaBelle Hu '24

According to a study done by Ipsos Retail Performance, the number of vegans in the US has increased from 290,000 in 2014 to almost 10,000,000 in 2019 [1]. This drastic change can be accredited to people becoming more environmentally and socially aware of the impacts of eating meat through social media. Companies reflect this growing trend as more vegetarian options are implemented in fast-food menus. In 2020, Eat Just became the first to gain regulatory approval in the commercial sale of cultured meat by the Singapore government. Their chicken bites are made up of 70% cultured chicken with the remaining ingredients being plant protein [2]. However, lab-grown meat is not the only attractive alternative; plant-based meat has also recently been implemented in many fast food restaurants. In 2019, Burger King introduced the Impossible Whopper, one of the first plant-based meats to be offered at any fast food chain. Other companies such as Starbucks, Applebee’s, and Little Caesars quickly followed suit, adding impossible meat into their menus as a vegetarian option [3]. Fast food chains have evolving incentives to modify their menus as research shows the benefits of including vegetarian options; a study of Cambridge students discovered that doubling the proportion of vegetarian meals increased vegetarian sales by between 41% and 79% [4]. The successful public response of creating more vegetarian options and the rise in popularity of meat alternatives encourages both businesses and scientists to expand their markets and research new methods of creating tasteful, attractive meat alternatives. 

But what are some of the driving factors behind the recent spike in vegetarian options?

One main reason people turn towards vegetarianism is the rising awareness of environmental determinants caused by animal farming in factories. Meat production has been cited as the most potent source of methane, a gas 80 times more effective in warming the atmosphere than carbon alone [5]. With the systematic process of animal farming commonly practiced by modern corporations, these farm animals constantly produce innumerable chemicals, infecting the atmosphere with their destructive properties. While these meat alternatives offer new flavors for foods, these goods must also be seen as pieces of a solution to the unending quest of limiting human detriments to the environment. 

Another reason people have limited meat in their diets is the health concerns regarding overconsuming this salty, fatty food. Although many people may assume that meat may make people stronger by providing protein and carbohydrates, studies have shown that regularly eating red-meat and processed meat raises the risk of type 2 diabetes, coronary heart disease, and certain cancers [6]. Overall, the recently-discovered health risks of consuming a gluttonous amount of meat prevent people from continuing to eat high amounts of meat and encourage them to pursue new, healthier alternatives to this protein. 

Despite these reasons, most people often hesitate to reduce their meat consumption as the distinct taste of meat is difficult to replicate. Although there are many protein substitutes such as eggs, beans, and tofu that can replace meat in the diet, they lack the salty, fatty components of meat that make it so delectable. However, with the advancement of modern technology, scientists have been experimenting with creating new alternatives to meat; their goal is to eliminate the environmentally damaging factory components of farming while maintaining the distinct flavor of meat.  

With science and technology, one alternative for factory meat, recreating living animal tissue, has been on the rise recently. Animal cell culture became a common laboratory technique in the mid 1900s, but the idea of maintaining live cells separated from their original tissue source stems from the 19th century [7]. Recently, scientists have applied this concept of growing cells independent of their sources to improve meat production. In 2013, Maastricht University revealed the first lab-grown burger, an amalgamation of around 20,000 individual cow muscle cells. The first person to try the cultured beef publicly was food researcher Hanni Rützler, who described the taste as “surprisingly close” to normally farmed meat [8]. However, even with the advancements of scientists, the process for creating tasteful lab-grown meat is still lengthy and nuanced.

Researchers cannot begin the muscle-growing-process with fully matured muscle fiber cells as the elongated form cannot be divided into two fibers. Instead, flexible cells are used, but there are many trade-offs with each option. For example, although pluripotent stem cells can be manipulated into many forms and are easily divided, they are more difficult to control than other more developed cells [9]. On the other hand, myoblasts, which naturally appear in animal muscles to repair damages, are easier to control, but they also don’t divide as easily.                       

Not only are these artificial patties filled with muscle fiber cells, but they also contain connective tissue and fat cells, which hold fiber cells in place and add flavor respectively. After the flexible cells are collected from the animal, they’re grown on beads or other scaffolds. As the diagram above shows, these scaffolds, made of polymeric biomaterials, provide structural support for cell and tissue development. Since cells communicate while forming normal tissue, difficulties arise when scientists isolate cells for culture. Isolated tissue lacks blood vessels, which supply inner cells with oxygen and food supply; thereby, the isolated cells lose survival signals from neighboring cells and devolve into apoptosis, a programmed cell suicide. Scientists counter this by testing various scaffolds. The most common scaffolds used in meat culture are collagen and gelatin since they’re derived from animals [10]. Overall, scaffolds are still being tested to better grow isolated cells as scientists work to make them more effective and plant-based.

In order to increase their efficiency, scientists often combine scaffolds with bioreactors, chambers for cell growth; this machine replicates animal body temperature while supplying nutrients and signals to the cells. The most common bioreactor used for cultivating meat is the continuous stirred tank reactor, which provides long-term sterility and reduced bubbling [11]. These machines allow growth of cells in suspension through mechanical stirring while maintaining high mass transfer of oxygen. Despite all of this, bioreactors are costly: the Soil and Water Conservation Society states that an average bioreactor will cost around $15,000 for installation, equipment, and labor [9].

Lab-grown meat can positively affect the environment by reducing detriments caused by animal factory farming; however, the process is expensive and has drawbacks in the type of cells used and in the environment the cells develop in. Therefore, some scientists have turned to plant-based meat, completely independent of animal produce. Patrick O. Brown, the founder of Impossible Foods, is a molecular biologist adamant on creating tasteful alternatives to animal meat. Dropping out of Stanford to create a burger business, Brown began by searching for molecules that create meat’s attractive flavor. Brown cites heme, a molecular cage of nitrogen surrounding an iron atom, as the “magic ingredient that makes meat taste unlike anything else on Earth.” Heme is a potent catalyst which serves as a precursor to hemoglobin; the compound extracts energy from food and creates a distinctive taste in meat. Brown uses a plant version of heme, leghemoglobin, found in soybean roots, to create “impossible meat” [12]. Leghemoglobin genes are inserted into yeast and brewed in vats, mimicking the method insulin and rennet are grown. Summarizing Brown’s propositions, plant-based meat serves as a viable option for meat alternatives, but developments are still being made in the taste and texture [8]. 

Both lab-grown meat and plant-based meat prove to be strong alternatives for animal factory-farmed meat. Although the development of these products may be expensive and relatively new, the positive response to these man-made meat products reveal promising horizons. With these alternatives, average citizens can also impact the environment as well as improve their health by reducing their meat intake. The world constantly grows with new technologies and ideas as people fight to create a healthier, happier planet and population. Like muscle cells germinating in a scaffold, meat alternatives continue to grow and develop, slowly becoming more advanced and attractive.