Imagine taking a bite of a hamburger: tasty and juicy, as ever. What if you were told that the hamburger was made in a laboratory? Would you be disgusted? Or maybe curious: “Is that really possible? How is it made? Is it safe to eat?”
“Cultured meat”, “cell-based meat” and “in vitro meat” are among the many names used to define animal tissue grown in a laboratory, and consumable as food. This is not a product that we can yet find in our local supermarket, but more than seventy companies worldwide have invested in this to become a reality in the future. I got interested in this subject because, as a food lover, I am seduced by the idea of eating meat without some of the negative aspects associated with it. I had many questions and I dug into this topic to learn about cultured meat. In the following paragraphs, we will take a closer look at the production processes, the final product, and the pros and cons of this food technology. Bon appétit!
How is cultured meat made?
In a nutshell, the idea is to reproduce the physiological steps of muscle formation in a controlled environment. The key is using skeletal muscle stem cells, which are obtained from a “tiny piece, or biopsy” of muscle tissue sampled from an animal under anaesthesia. Muscle stem cells are responsible for maintaining and regenerating the tissue, in case of injuries, due to their ability to proliferate and differentiate into new muscle fibres. In short, once isolated, muscle stem cells are placed in a large cultivator called a 'bioreactor' which provides the same temperature and oxygen conditions of the living animal. The cells are nourished with a medium containing all the growth factors and nutrients necessary for their proliferation and differentiation. According to Mosa Meat, one of the leading cultured meat companies, a biopsy of 0,5 gr of meat (with 33,000 initial muscle stem cells) is enough to grow, within a few weeks, almost a trillion muscle cells which will fuse to form new muscle fibres of 0.3 mm long (1,2). These will be placed in edible scaffolds that allow a flux of nutrients to conclude the growing process in the desired shape. In some cases, this last step is obtained through 3D-bioprinting techniques, similar to biomedical engineering attempts for producing organs suitable for transplantation. The overall process, here described, may differ in some details from company to company. In any case, after some final quality controls, the meat will be ready to be cooked.
What does the final product look like? How does it taste?
Today's technology mostly allows us to obtain “basic” products, rather similar to ground meat than a genuine steak. Real skeletal muscles – with their organised fibres, blood vessels, nerves, connective tissue and fat cells – are far too complex, for now, to be reproduced in vitro. Nevertheless, a fair variety of products might soon be available: lab-grown beef burgers, chicken or fish nuggets, foie gras, pork sausages, bacon and meatballs, crustaceans’ chips or sashimi-like fish. The goal is to give consumers the same sensory and nutritional experience of traditional meat. Compared to plant or fungi-based meat substitutes, cultured meat promises to better preserve the 'molecular imprint’ of taste according to the producers: in terms of protein, it contains actin and myosin like any muscle tissue; in terms of fat, it contains triglycerides, saturated, mono- or poly-unsaturated fats in similar proportions to conventional meat (3). Nevertheless, it is reasonable to think that this young technology is far from achieving the perfect molecular balance to fully mimic the complexity and the diversity of meat appearance, taste, aroma and texture. Furthermore, to avoid animal-derived products, the procedure might involve the use of plant-based elements (such as edible scaffolds) which can impact on the final taste. On the other hand, seasoning and cooking methods might help the final product in better mirroring the original.
Which are the arguments in favour of cultured meat?
One argument is surely evident: avoiding animal-killing by removing animals from the equation. Already in 1931, Winston Churchill had spoken out in favour of this futuristic technology: “We shall escape the absurdity of growing a whole chicken in order to eat the breast or wing, by growing these parts separately under a suitable medium.” Global meat consumption has more than tripled since then, due to an increase in world wealth. Nowadays, around 80 billion animals (mostly chicken) are slaughtered each year for meat (4), while companies like Mosa Meat (producing cultured beef) promises 80 thousand burgers from one unique animal biopsy (2). In addition, the world population is expected to reach 9 billion by 2050 with a consequent 70% increase in demand for food, which will be a challenge due to limited resources available (1).
Cultured meat is proposed as a sustainable alternative to farming for meat which is the first food industry for environmental impact and use of resources (land, crops and water). Meat production is currently responsible for around 14% of all greenhouse gases emission worldwide, which majority derive from beef herds – due to the methane produced by their digestive system – followed in order by lambs, prawns, pigs and poultry (5). Additionally, farming animals is a poorly efficient method for converting resources into calories and proteins: beef converts only 3% of the provided nourishment into the final product, while pork and poultry do better with respectively 9% and 17-21% (6). For comparison, if we used these croplands for our nutrition, we could feed 4 billion more people (7).
This innovative food technology may also address some public health issues: by reducing the risk of zoonoses (pathogens jumping the species barrier from animals to humans) due to intensive farming, by decreasing the consumption of antibiotics in animal agriculture which fuels the development of antibiotic resistances, and by avoiding faecal contamination which cause infections from pathogens such as E. coli, Salmonella or Campylobacter. Looking further into the future, we could also produce cultured meat with a healthier nutritional content by decreasing the content of the saturated fats in favour of unsaturated fats, or even replacing them with Omega-3. It may also be possible to modify animal cells to express other micronutrients (such as vitamins) particularly beneficial for human health (1).
Which are the criticisms raised against cultured meat?
The first criticism concerns the delicate balance between animal welfare and the economic feasibility of the current cultured meat production process. In fact, these industries struggle to avoid the use of certain animal-derived “ingredients” which are highly efficient in recreating the conditions for muscle growth but could involve animal suffering. We are mainly talking about Foetal Bovine Serum which contains all the proteins and factors to favour the growth of cells derived from various animals. Some of the leading companies have publicly announced to have overcome this challenge by finding alternative mediums effective on their specific cell culture (8). Despite this improvement, this is not yet applicable on a large-scale industrial production as some of the replacing components of this non-animal-derived medium are expensive and can’t be easily supplied. In 2013, the first lab-grown burger publicly tasted on BBC cost $300,000, since it was produced with compounds derived by medical science.
Another matter of controversy concerns whether cultured meat would be significantly less environmentally impactful than the current meat industry. Although fewer animals and land would be required, the production process still requires a lot of energy: to supply the facilities, to cool down the system, to produce medium components and more. There is no consensus among publications on the actual emissions of cultured meat, but its sustainability may strongly depend on the use of renewable energy throughout the process (1,9,10). In addition, it is important to correlate the energetic and ecological impact of each cultured product with its original counterpart: while cultured beef may bring substantial benefits (compared to current bovine industry), the benefit may not be as evident in the case of pigs or poultry, which are less environmentally impactful than beef. Finally, cultured meat may not be competitive enough compared to plant-based substitutes, which are less expensive and less energy-demanding to produce. In some cases, vegetarian substitutes have been quite successful in replicating certain meat products in taste (11).
A final concern is product safety, specifically for the presence of culture medium residues in the final product. While the use of antibiotics and fungicides (used to keep the conditions sterile) have been highly limited (or even removed) by many companies, it is not clear what legislation would decide for growth hormones that are currently prohibited in traditional farming by several countries (including the Europe Union). Additionally, the high cellular proliferation might cause genetic dysregulation, as happens in cancer cells, with yet unknown consequences (1), and a similar concern would arise for the use of voluntary genetic modifications to alter, for example, fat production.
What will we eat in the future?
We have seen how cultured meat aims to offer an ethical and environment-friendly product appealing to the ordinary consumer, but the challenges to achieve all these expectations are not few. Between 2020 and 2021, the investments directed to this industry have more than tripled (from 400M $ to 1.4B $) (12), but it’s not clear if and when cultured meat will get on the shelves of our local supermarket. A first step was taken in Singapore in 2020, when the national Food Agency approved the first cultured chicken of Eat Just, Inc. that now can be tasted in a few restaurants of the city. In order to quickly ramp up to an industrial scale, some companies may start offering plant-based products flavoured with cultured meat (easier to supply in small quantities). Another useful application for this technology will be to provide food in space: the European Space Agency is testing the possibility of producing cultured meat where traditional meat cannot be provided. A pilot experiment was run in 2019 where bovine muscle cells cultured by Aleph Farms were taken on the International Space Station and were successfully grown on a small-scale scaffold.
In any case, the sixth Intergovernmental Panel on Climate Change (known as IPCC) report, released at the beginning of 2022, recognizes all types of alternative proteins, including cultured meat, as possible means to mitigate climate change. In a few words, current conditions may require us to revolutionise our food system in the coming years. This won’t mean wiping out the farmed meat industry, but rather developing a parallel and competitive market capable of achieving a significant impact.
So, my question to you, dear reader: when the day comes that you stand in front of a cultured hamburger... will you take that bite or not?
References
1. Chriki, S., & Hocquette, J. F. (2020). The Myth of Cultured Meat: A Review. Frontiers in Nutrition, 7. https://doi.org/10.3389/fnut.2020.00007
2. Growing Beef. (2020). Mosa Meat. https://mosameat.com/growing-beef
3. Paul-Gera, K. (2021, September 17). How we make real meat. Mosa Meat. https://mosameat.com/blog/how-we-make-real-meat
4. Ritchie, H. (2017, August 25). Meat and Dairy Production. Our World in Data. https://ourworldindata.org/meat-production
5. Ritchie, H. (2020, January 15). Environmental Impacts of Food Production. Our World in Data. https://ourworldindata.org/environmental-impacts-of-food
6. Shepon, A., Eshel, G., Noor, E., & Milo, R. (2016). Energy and protein feed-to-food conversion efficiencies in the US and potential food security gains from dietary changes. Environmental Research Letters, 11(10), 105002. https://doi.org/10.1088/1748-9326/11/10/105002
7. Cassidy, E. S., West, P. C., Gerber, J. S., & Foley, J. A. (2013). Redefining agricultural yields: from tonnes to people nourished per hectare. Environmental Research Letters, 8(3), 034015. https://doi.org/10.1088/1748-9326/8/3/034015
8. Messmer, T., Klevernic, I., Furquim, C., Ovchinnikova, E., Dogan, A., Cruz, H., Post, M. J., & Flack, J. E. (2022). A serum-free media formulation for cultured meat production supports bovine satellite cell differentiation in the absence of serum starvation. Nature Food, 3(1), 74–85. https://doi.org/10.1038/s43016-021-00419-1
9. The Good Food Institute, Scharf, A., Breitmayer, E., & Carus, M. (2019). Review and gap-analysis of LCA-studies of cultured meat.
10. Cultivated meat LCA/TEA report analysis. (2021). The Good Food Institute. https://gfi.org/resource/cultivated-meat-lca-tea-report-analysis/
11. McDermott, A. (2021). Looking to “junk” food to design healthier options. Proceedings of the National Academy of Sciences, 118(41). https://doi.org/10.1073/pnas.2116665118
12. O’Donnell, M. (2022, April 14). Investment resources (2021) | Alternative protein startups | GFI. The Good Food Institute. https://gfi.org/investment/
This article was specialist edited by Dr. Barbara Gayraud-Morel and copy edited by Kyrie Grasekamp.
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