A new preprint study from researchers in the US has concluded that the environmental impact of cultivated meat is probably ‘orders of magnitude’ worse than traditional beef, based on current and near-term production methods. But experts are divided on whether the study, which has yet to undergo peer review, makes valid assumptions.
Cultivated meat, which is produced from animal cells grown in a lab rather than raising, farming and slaughtering livestock, has been proposed as a significantly greener alternative to conventional meat. For example, an analysis by scientists from Oxford University and the University of Amsterdam back in in 2011 estimated that cultivated meat would require 7–45% less energy to produce than the same volume of pork, sheep or beef. More recently, findings by the Dutch environmental consultancy CE Delft indicated that cultivated meat would cause up to 92% less global warming and 93% less air pollution compared to conventional beef, while also using up to 95% less land and 78% less water.
But now researchers at the University of California, Davis, suggest these and other studies have underestimated the environmental impact of cultivated meat, and in particular the cost of producing the highly refined growth medium that they say its near-term production methods will continue to rely on.
The UC Davis team conducted a life-cycle assessment of the energy required and greenhouse gases emitted in all stages of cultivated meat production. In scenarios where the growth medium is prepared at very high purity, carbon dioxide equivalents emitted for each kilogram of meat produced were four to 25 times greater than the median value for retail beef.
UC Davis food scientist Derrick Risner, the preprint’s lead author, explains that the discrepancies in results from his paper and previous research are mostly attributable to ‘differences in assumptions in our near-term production model versus future production models with some more aggressive assumptions on technology advancement’.
Hanna Tuomisto, an associate professor of sustainable food systems at the University of Helsinki who co-authored the 2011 study when she was at Oxford, says the main difference is that the new UC Davis work included the purification process to remove endotoxins from all ingredients used in the culture medium, including water, which is very energy intensive.
‘Many of the cultured meat companies are saying that they are able to use food-grade ingredients so that they don’t necessarily need to be pharma-grade ingredients,’ Tuomisto continues. ‘My view is that this paper is overestimating the energy requirements for the endotoxin removal process.’ Others appear to agree.
‘The reality is that the fundamental assumption in the report does not reflect actual industry plans or sourcing practices for cell feed,’ Cellular Agriculture Europe, a coalition of food companies based in Brussels, stated. ‘No company will scale up using expensive pharmaceutical-grade ingredients, and we have already proven that we do not need them.’ The non-profit Good Food Institute based in Washington, DC echoed these concerns.
Steps to sustainability
Food company Eat Just, whose cultured chicken has been approved for sale in Singapore since 2020, is also sceptical about the new findings. ‘The UC Davis study is largely based on arguments that nutrients fed to cells will continue to be pharmaceutical grade,’ says Eat Just spokesperson Andrew Noyes. ‘That assumption is flawed and doesn’t align with the vision or actions of this young and rapidly evolving industry,’ he adds .
Meanwhile, Cindy Tian – an animal science professor at the University of Connecticut who has co-authored a study that induced bovine pluripotent stem cells for the first time in the hopes of overcoming challenges for cultivated meat, welcomes the study. She has previously told Chemistry World that the process of making meat from animal cells remains ‘extremely inefficient’ and appears unsustainable.
‘I am glad someone is telling the truth,’ Tian states, referring to the new UC Davis preprint. ‘Years of research and many breakthroughs will be necessary for cultured meat to be even close to the current beef production system,’ she adds, noting that cattle domestication has an 11,000-year history while cultivated meat has only been around about a decade .
D Risner et al, bioRxiv, 2023, DOI: 10.1101/2023.04.21.537778