Cultured meat has been growing in popularity as a result of improved greenhouse gas emission efficiency of production promised by this alternative. One of the most salient comparisons made is with beef, as this type of meat is a highly emissions-intensive product. Consequently, the role of livestock in supporting human wellbeing is becoming an increasingly contentious subject with regards to a sustainable diet.
Image Credit: Firn/Shutterstock.com
Why has lab-grown meat grown in popularity since the climate crisis?
The demand for food sourced from animals increases as the population continues to grow. Animal-free alternatives and manufactured items that serve as substitutes for meat and animal-based products in the diet are increasingly emerging in response to the limited supply. Ingredients sourced from both animals and plants are two approaches that have started to become employed to produce alternative meats.
In contrast to traditional meat, cultured meat addresses a litany of climate associated problems which include resource shortages, greenhouse gas emissions/pollution, long term sustainability; moreover, it promises to address financial concerns, animal welfare ethics, and public health issues which Both, directly and indirectly, impact the climate crisis.
The merits of these products compared to traditional animal products appear to be dependent on the metric that is being compared, the manufacturing system used, and the reference animal or plant species from which cultures are derived.
However, technological innovations continue to improve, allowing the efficiency of both alternative and conventional food production systems. As the need to sustainably address food security demands across the world, this efficiency will be requisite.
What is cultured meat?
Cultured meat is an emerging technology in which muscle cells are produced via tissue culture in a controlled laboratory environment in contrast to traditional whole animal livestock systems of pastoral farming. It is also referred to as in vitro, synthetic, or lab-grown meat. This tissue engineering technology is harnessed to produce meat at manufacturing scales using a bioreactor.
There is a substantial amount of practicality surrounding cultured meats, as tissue culture methods for in vitro meat culturing all avoid livestock problems and alleviate concerns associated with animal welfare. The prototype of in vitro meat was developed in 2013 by pharmacologist Dr. Mark Post; at the time, this required three months and $330,000 to produce a 5-ounce ‘patty’ in a laboratory. Despite the 8 years since its inception, the industry is still in the early stages and limited by high cost and inefficient technology which remain a block to widespread application and commercialization.
The impact of lab-grown meat on sustainability and the environment
In traditional livestock-sourced meat, there is a low conversion rate from each production, with only 5–25% of the animal processed as edible meat. This results in several issues, which include greenhouse gas emissions, land usage, and water and energy consumption. Relative to conventionally produced meat livestock systems in Europe, cultured meat has been indicated to involve ~ 78%–96% reduced greenhouse gas emissions, 99% reduction in land use, and between 82 and 96% reduction in water use.
Cultured meat, therefore, represents a sustainable and eco-friendly method to produce meat due to its efficiency; it does not require the growth of other supporting tissues and functional structures once the technology has advanced.
Although it is currently in its early stage, limited by technical challenges (namely lacking cost- and resource-effectiveness for production at scale)and issues surrounding consumer acceptance), it is believed that the overall energy balance will tip in favor of cultured meat production environmental benefits it offers. It has a compelling sustainability argument, being capable of alleviating global food security stress as well as contributing to the minimalization of greenhouse gas emissions by the food production sector.
The promise of feeding a growing global population while minimizing planetary resources and offering more environmentally efficient production circumvents the need for intensive livestock production and animal slaughter. Other compelling arguments alongside in support of cultured meat include:
- The promise of improved macro and micro nutritional profiles relative to traditional animal foods as a result of increased protein composition and antibiotic-free methods of production
- Increased food safety and traceability via technological science
- Indistinguishable taste on texture
Why is there a need for cultured meat?
Since the mid-20th century, the consumption of chicken has increased across the world; in 2019 2.1 billion chickens were slaughtered for food. Due to the research suggesting the negative health effects of red meat, chicken has become increasingly popular and is now leading in the most consumed terrestrial meat in the world at 132 million metric tons.
Due to the technological advances in intensive meat farming, the ability to supply a range of populations has increased, which is subsequently increased the demands for it; indeed, publicly funded technological innovations have been scaled up by the private sector and have been supported by governmental policy regimes.
Planet sources of protein provide the majority – 57%– of the global protein supply; meat (18%), dairy (10%) fish and shellfish (6%), and other animal products (9%) make up the rest of the global supply. Greenhouse gas emissions attributed to livestock supply trains account for 14.5%.
In addition, the emission intensity which is defined as the number of greenhouse gases produced per unit of output produced, of livestock is highly variable and is dependant on the product produced, the species of animals from which it is derived, and other environmental factors.
As a consequence of this, protein-based livestock emissions range from 31 CO2eq/kg for eggs to 404 kg CO2eq/kg for Buffalo. Moreover, the emission intensities for animal-sourced foods are much greater than plant products (notes, pulses, and peas for example which produce 2.6, 8.4, and 4.4 CO2eq/kg, respectively).
The limitations and pushback against cultured meat in the climate crisis
Despite the widespread understanding of the need to develop sustainable meat alternatives, there is widespread pessimism regarding the challenges of scaling up production, cost, and food safety. Indeed, cultured meat has opened the biotechnology industry to criticism and attack by activist groups.
These groups create fear around genetically modified organisms as they are often framed as unnatural and therefore unsafe to eat. This has subsequently resulted in hesitancy by academic researchers and developing countries to venture and engage in the field of agricultural biotechnology.
Consequently, there is a need to prevent vilification of alternative systems of food and to accurately communicate how the adoption of these innovations is essential in ensuring global food security. Failing to do so can increase the chance for misinformation and fear which will preclude access to agricultural biotechnology being implemented in food production across the world.
In addition to cultural pushback against cultured meats, there are several technical challenges to producing it:
One of the challenges to cultured meat production is a selection of the appropriate cell source for animal tissue culture. One of the main challenges is identifying a large enough number of homogeneous starter cells from which proliferation and differentiation can occur.
One obvious choice is the use of stem cell lines, however, there are some problems associated with them which include genetic instability and phenotypic drift. muscle stem cells, called satellite cells, are the most widely studied source due to their differentiation potential. However, they are still hampered by cell mutations that occur during the proliferation process. This results in limited amplification ability of tissue cultures.
Research into pluripotent stem cells has recently received attention as they can effectively proliferate in large masses. Recently, several strategies have been identified but generating pluripotent stem cells without any genetic modification is promising – but challenging.
Proliferation and differentiation
Most cells have a limited capacity for division. This is called Hayflick’s limit, and it limits any large-scale attempts at cultures of meat tissue in a laboratory. There are ways to overcome this limitation for example by using telomerase which extends the length of telomeres. Telomeres shorten with each round of replication and once they reach their limit, the cell is no longer able to proliferate. By regulating the expression of telomerase, or by exogenously adding telomerase, cell regeneration potential can be effectively improved. This is therefore conducive to stable, large scale, and rapid proliferation of animal cells
Other limits to its widespread production include:
- The use of microcarriers as muscle cells require an anchor
- Choice of suspension culture to prevent the disruption to, and enable the tolerance of suspended cells as they are sensitive to changes in pH, temperature, and shear force
- Bioreactors as, at present, there are difficulties associated with them as well as the process of scaling up cultured meat production
- The use of serum-free media: despite serum containing the appropriate attachment factors, micronutrients, growth factors, hormones, and protective elements that promote the proliferation of cells, it also increases the risk of contamination with viruses or prions
Amid a climate crisis, there is an increasing demand and further development of biotechnologies that will allow the large-scale production of cultured meat. It is projected that cultured meat may ultimately compete with traditional agriculture-derived meat as a sustainable choice, which holds a large potential in relieving the environmental, and economic burden from a growing population with the demand for meat.
Continue reading about lab-grown meat here.
- Balasubramanian B, Liu W, Pushparaj K, Park S. (2021) The Epic of In Vitro Meat Production-A Fiction into Reality. Foods.. doi:10.3390/foods10061395
- Zhang G, Zhao X, Li X, et al. (2020) Challenges and possibilities for bio-manufacturing cultured meat. Trends in Food Science & Technology. doi: 10.1016/j.tifs.2020.01.026.
- Lynch J, Pierrehumbert R. (2019) Climate impacts of cultured meat and beef cattle. Front Sustain Food Syst. doi:10.3389/fsufs.2019.00005.
- Van Eenennaam AL, Werth SJ. (2021) Animal board invited review: Animal agriculture and alternative meats - learning from past science communication failures. Animal.. doi: 10.1016/j.animal.2021.100360.