According to the latest analysis, replacing 20% of the world’s beef consumption with microbial protein like Quorn could halve the destruction of the planet’s forests over the next three decades.
The move would also halve emissions from the global food system by reducing tree felling and methane emissions from livestock. Previous studies have shown that meat alternatives have a smaller environmental footprint, but this latest analysis is the first to assess what impact this could have on the world.
Deforestation is also ravaging wildlife but is proving very difficult to stop. Experts say the best way is to curb demand for the products that are driving the destruction, for example by replacing them with greener alternatives. Microbial protein is brewed in warm bioreactors like beer, feeding the microbes sugar. The high-protein product could taste and feel like meat and be just as nutritious, the researchers said.
Today, 83% of arable land is used for livestock and their forage crops, but the meat and dairy products produced account for only 18% of the calories consumed by humans. Ruminant meat production — mainly beef, but also lamb and goat — has more than doubled since 1961, but a number of studies have shown that meat consumption in wealthy nations must fall drastically to overcome the climate crisis.
“The food system is responsible for a third of global greenhouse gas emissions, with ruminant meat production being the largest single source,” said Dr. Florian Humpenöder, a researcher at the Potsdam Institute for Climate Impact Research (PIK) in Germany, who led the study. “The good news is that people don’t have to be scared of only eating vegetables in the future. You can still eat burgers and things like that, just these burger patties are made in a different way.”
The research focused on microbial meats that had been produced on an industrial scale for 20 years and were already available, said Dr. Isabelle Weindl, also at PIK. “Even taking into account the sugar as a starting material, microbial protein requires much less agricultural land in comparison [with] Ruminant meat.” Previous studies have shown that the protein quality of microbial meat matches that of beef, but uses 90% less land and water and produces 80% fewer greenhouse gas emissions.
The study, published in the journal Nature, used computer models that included mean projections of socioeconomic factors such as rising demand for beef, growing world population, increases in income and shifts in international trade.
The 56% reduction in deforestation – 78 million hectares (193 million acres) – attributed to replacing one-fifth of beef with microbial protein occurred in Latin America and sub-Saharan Africa. In the modelling, significant deforestation was still occurring due to the production of other foods such as palm oil and cocoa.
The researchers found that microbial protein substitution largely offset the projected increase in demand for beef, meaning no new grazing land had to be cleared into forests. Increasing the proportion of beef substituted to more than 20% led to falling yields as much of the deforestation had already been prevented, with 50% replacement leading to an 82% reduction in deforestation by 2050.
Microbial protein can be made from a range of microorganisms, including bacteria, but the main source on the market today is made from fungi, with Quorn being the market leader. “The best meat alternative is to eat less,” said Humpenöder. “But [microbial protein products] can make the switch to meat easier.”
The effect of plant-based meat alternatives was not analyzed in the study, but these are also likely to significantly reduce the environmental impact. Meat from animal cells cultivated in bioreactors is still at an early stage of development and was not included in the study due to a lack of suitable data.
dr Tilly Collins of Imperial College London, who was not part of the study team, said: “While the predictions of these models depend heavily on our ability to provide such a protein substitution, there is no doubt that the efficiency of bioengineered alternatives offers enormous future potential for a more sustainable food supply.
“Governments and food manufacturers need to coordinate to develop appropriate standards [for microbial protein] and hence future public confidence. Our nuggets may never be the same again.”
The bioreactors used to make microbial proteins need to be heated, and using high-carbon power sources would offset some of their benefit, but green power is spreading fast as costs continue to fall.
Humpenöder said: “Microbial protein should not be viewed as a silver bullet, but as a building block in a major transformation of the entire food and farming system, combined with reducing food waste, incentivizing healthier eating and disincentivizing the sale of products with high environmental impact.” “