Switching out just a fifth of the beef we eat in favor of “alternative” beef made from microbes such as fungi could halve deforestation globally and drastically reduce greenhouse gas emissions and biodiversity loss, researchers in Europe have found.
In a study published in the journal Nature, the researchers included microbial protein—a meat alternative grown in fermentation tanks—in a computer model simulating the entirety of the global food and agriculture system. The results were striking, suggesting that substituting just 20% of the beef in our diets for microbial protein by 2050 could result in a 56% reduction in annual deforestation worldwide.
That’s because microbial protein, which can offer similar or even better nutrient profiles than beef, requires a fraction of the land, water and resources that cattle or even vegetables do.
“The substitution of ruminant meat with microbial protein in the future could considerably reduce the greenhouse gas footprint of the food system,” said Florian Humpenöder, a researcher at the Potsdam Institute for Climate Impact Research and lead author of the study. “The good news is that people do not need to be afraid they can eat only greens in the future. They can continue eating burgers and the like, it’s just that those burger patties will be produced in a different way.”
Cattle are responsible for 14.5% of human-caused greenhouse gas emissions, and comprise by far the largest source of food system emissions. More than a quarter of the planet’s ice-free land is used for cattle grazing [PDF], and a further 33% of all cropland is used to produce food for cattle. Beef production is the number one driver of deforestation globally.
In the simulations, “the reduced numbers of cattle do not only reduce the pressure on land but also reduce methane emissions from the rumen of cattle and nitrous oxide emissions from fertilizing feed or manure management,” Humpenöder said. “So replacing minced red meat with microbial protein would be a great start to reduce the detrimental impacts of present-day beef production.”
Tomas Linder, a co-author of the study and a researcher at the Swedish University of Agricultural Sciences, said the fact of the matter is that microorganisms are simply far more efficient than other living things when it comes to making protein.
“The key difference is that microorganisms can make protein from simple carbon and nitrogen compounds like sugar and ammonia,” Linder said. “Animal cells, on the other hand, cannot ‘make’ protein from scratch; they just convert one form of protein into another, for example soy protein into muscle protein.”
One consequence of this, Linder told Forbes Sustainability, is the production of nitrogen in the form of animal urine and feces, which pollutes rivers and lakes, and also generates nitrous oxide, a potent greenhouse gas.
“Microorganisms, on the other hand, have almost perfect so-called nitrogen utilization efficiency, which means that nearly all the nitrogen fed to the microorganism ends up in the final product,” he explained.
Fermentation-based meat alternatives have been described by the non-profit Good Food Institute as the “third pillar of the alternative protein industry,” after plant-based meat (think Impossible Foods or Beyond Meat) and cultured meat (actual animal cells grown without using animals, being pioneered by firms such as Mosa Meat). The most popular of the microbial proteins—mycoprotein, based on a type of fungus—have been around for years, with Quorn being the best-known example. But there has been an explosion of venture capital investment in companies working on more sophisticated, more meat-like mycoproteins, with products from U.S. firms such as The Better Meat Co. and Nature’s Fynd, and Swedish startup Mycorena creating ingredients that are edging ever closer to tasting like the real thing.
None of this is to say, however, that microbial protein is the answer to all the planet’s climate and food production woes. For one thing, the results revealed in Nature are non-linear, meaning that substituting much beyond 20% beef with microbial protein won’t yield proportionately greater environmental gains. That’s because of what the authors call a “saturation effect”: since a considerable share of deforestation is already avoided in the 20% substitution scenario, the land-saving effects diminish with increasing substitution levels.
But, perhaps more importantly, the production of any food requires energy. In the case of microbial protein, the fermentation process uses bioreactors that run on electricity. For this reason, any large-scale move towards microbial protein will need to be complemented by the decarbonization of energy systems, investing in renewable energy resources wherever that protein is grown.
“Microbial protein is a promising and readily available option to reduce the detrimental impacts of ruminant meat production,” Humpenöder said. “However, it should not be perceived as a silver bullet to solve the climate or biodiversity crises. Instead, it should be integrated into a portfolio of options that address climate change and biodiversity loss simultaneously.”
The paper “Projected environmental benefits of replacing beef with microbial protein” can be viewed here. A subscription is required to view the full article.