According to FoodNavigator, recent research from the University of California, Davis suggests that the global warming potential of cultured meat could be 4-25% higher than that of conventional beef if a highly refined growth medium is used in its production.

A hidden truth?

Cultured meat, which involves producing meat from animal cells using a combination of biotechnology, tissue engineering, molecular biology, and synthetic processes, is considered a more ecologically sustainable alternative to conventional meat production.

Indeed, many foods are considered more environmentally sustainable than intensively produced animal-derived meats. Globally, animal production contributes to approximately 18% of anthropogenic greenhouse gas emissions (GHGs), a significant contribution to water stress, and a key driver of deforestation.

However, a new pre-print study by researchers from the University of California, Davis (which has not yet undergone peer review) suggests that cultured meat production could be worse for the environment than conventional beef production.

Does cultured meat consume more resources?

The researchers conducted a life cycle assessment (LCA) from cradle to grave of cell-based meat, according to what they describe as "current production methods." The study used findings from a pre-printed LCA of the cradle-to-gate production of the cultured meat growth medium, also conducted at UC Davis.

The growth medium (which contains the nutrients and growth factors cells need to grow) used in the researchers' model is E8—a growth medium designed for stem cell research and believed to be scalable and easily modified for industrial-scale cultured meat production.

"The authors believe that the use of E8 or a similar refined growth medium will be necessary, given the sensitivity of animal cells in vitro to medium impurities, compared to yeast or bacterial cells," explained food researcher Derrick Risner and his team from UC Davis.

The results of the life cycle impact assessment (LCIA) of cultured meat suggest that production based on purified components of the growth medium leads to a higher global warming potential (kg of equivalent carbon dioxide [CO2e]) than beef.

"Without the purification of the growth medium components, the global warming potential of the glucose consumption rate (GCR) is about 25% higher than the reported average global warming potential of retail beef."

Overall, the study indicates that cultured meat is likely to consume more resources than most meat production systems, according to the researchers' analysis.

"We... hope that our LCA will provide evidence of the need for further critical environmental examination of new food and agricultural technologies," note the study authors.

Comparisons with previous research

This study is not the first to suggest that cultured meat production may not be as environmentally sustainable as initially believed.

While cultured meat uses much less land and water, its production is energy-intensive. In 2019, researchers from the Oxford Martin School conducted a comparative study on the greenhouse gas emissions produced by cultured meat and conventionally farmed beef in the current energy system.

The study suggested that in some cases, cultured meat manufacturing could lead to more global warming due to the difference in gas emissions: methane vs. CO2. Warming caused by carbon dioxide emitted from the current energy system would persist, while warming caused by methane ceases after just a few decades.

At the time, the researchers suggested that a "widespread" transition to a decarbonized energy system would be necessary for cultured meat production to become a clear winner in terms of environmental sustainability.

However, the UC Davis findings contradict some recent research investigating the ecological sustainability of cultured meat production.

Earlier this year, a group of international researchers published a study in The International Journal of Life Cycle Assessment (IJLCA), predicting the ex-ante LCA of commercial-scale cultured meat production in 2030.

Using data from more than 15 companies working in cultured meat production and its supply chain, the study found that land use with cultured meat is low, and nitrogen-related emissions and air pollution associated with cultured meat are also smaller than its conventional counterparts.

But as with the 2019 study, the research found that the production of cultured meat is energy intensive. Its carbon footprint is "substantially" lower than that of beef," the researchers conclude, but how it compares to chicken and pork depends on energy mixes. “While the production of cultured meat and its upstream supply chain is energy intensive, the use of renewable energy can ensure that this is a sustainable process. alternative to all conventional meats."

Focus on growing media

The UC Davis study drew criticism from cultured meat advocates. According to the international non-profit organization Good Food Institute (GFI), "several" key assumptions in the UC Davis study do not align with "current or expected" practices for sourcing and purifying the ingredients of cell culture media.

“Ingredients of cell culture media can be obtained in a variety of ways. The American Davis authors assume in their study that the media ingredients will be produced and purified on an individual basis, as in the pharmaceutical industry," GFI noted.

But if the cultured meat industry followed this method of sourcing and purifying media inputs, the costs would likely be too high for the vast majority of products to be competitive with conventional meat, we're told.

“As the UC Davis study demonstrates, it also comes at a high environmental cost. So it wouldn't make economic or environmental sense for cultured meat to take this method forward. It wouldn't even be necessary."

According to GFI, cultured meat companies are aware of these challenges and have gradually moved towards a supply chain with media inputs that are suitable for use in food production rather than "built for pharmaceuticals". The IJLCA study, for example, used "very different" assumptions for media contributions, based on the contributions of companies involved in the industry's supply chain.

From the perspective of the UC Davis researchers, they were transparent about the LCA growth medium made and used in the study, which is available in pre-print: Cradle-to-Gate Life Cycle Assessment of Growth Media cultured meats: a comparison of Essential 8™ and Beefy-9. This study has not been certified by peer review.

“We examined an established growth medium (Essential 8) and a proposed growth medium (Beefy-9). A key finding is that the use of antibiotics in the growing medium can substantially increase the environmental [impact] of the growing medium,” UC Davis' Risner told FoodNavigator. "Our animal cell-based meat life cycle assessment did not include any antibiotics."

The conclusions of the study are subject to change

GFI is also wary of the UC Davis researchers' findings because the study has not yet gone through a full peer review process. This, as GFI points out, means that the study's assumptions and conclusions are subject to change.

Risner confirmed that articles have been submitted to peer-reviewed journals and explained that preprints may be submitted (or even encouraged to be submitted) during the journal's submission process, depending on the journal.

"We are open to feedback through peer review or other relevant avenues that make our work more informative," he told this publication. "These articles are also derived from my PhD thesis, so they have been reviewed at that level."

Sources:​

'Environmental impacts of cultured meat: A cradle-to-gate life cycle assessment' Pre-print posted online 21 April 2023 (yet to be certified by peer review) DOI: https://doi.org/10.1101/2023.04.21.537778 Authors : Derrick Risner, Yoonbin Kim, Cuong Nguyen, Justin B. Siegel, Edward S. Spang

'Cradle to production gate life cycle assessment of cultured meat growth media: A comparison of Essential 8™ and Beefy-9' Pre-print posted online 21 April 2023 (yet to be certified by peer review) DOI: https://doi. org/10.1101/2023.04.21.537772 Authors: Derrick Risner, Patrick Negulescu, Yoonbin Kim, Cuong Nguyen, Justin B. Siegel, Edward S. Spang

Frontiers in Sustainable Food Systems​Climate Impacts of Cultured Meat and Beef Cattle' Published 19 February 2019 DOI: https://doi.org/10.3389/fsufs.2019.00005 Authors: John Lynch and Raymond Pierrehumbert