Would you eat dried microbes? This company hopes so.

A company best known for sucking up industrial waste gases is turning its attention to food. LanzaTech, a rising star in the fuel and chemical industries, is joining a growing group of businesses producing microbe-based food as an alternative to plant and animal products.

Using microbes to make food is hardly new—beer, yogurt, cheese, and tempeh all rely on microbes to transform raw ingredients into beloved dishes. But some companies are hoping to create a new category of food, one that relies on microbes themselves as a primary ingredient in our meals.

The global food system is responsible for roughly 25% to 35% of all human-caused greenhouse gas emissions today (depending on how you tally them up), and much of that comes from animal agriculture. Alternative food sources could help feed the world while cutting climate pollution.

As climate change pushes weather conditions to new extremes, it’s going to be harder to grow food, says LanzaTech CEO Jennifer Holmgren. The company’s current specialty, sucking up waste gases and transforming them into ethanol, is mostly used today in places like steel mills and landfills.

The process the company uses to make ethanol relies on a bacterium that can be found in the guts of rabbits. LanzaTech grows the microbes in reactors, on a diet consisting of gases including carbon monoxide, carbon dioxide, and hydrogen. As they grow, they produce ethanol, which can then be funneled into processes that transform the ethanol into chemicals like ethylene or fuels.

A by-product of that process is tons of excess microbes. In LanzaTech’s existing plants where ethanol is the primary product, operators generally need to harvest bacteria from the reactors, since they multiply over time. When the excess bacteria are harvested and dried, the resulting powder is high in protein. Some plants using LanzaTech’s technology in China are already selling the protein product to feed fish, poultry, and pigs.

Now, LanzaTech is expanding its efforts. The company has identified a new microbe, one they hope to make the star of future plants. Cupriavidus necator can be found in soil and water, and it’s something of a protein machine. The company says that after growing, harvesting, and drying the microbes, the resulting powder is more than 85% protein and could be added to all sorts of food products, for either humans or animals.

Roughly 80 companies around the world are making food products using biomass fermentation (meaning the microbes themselves make up the bulk of the product, rather than being used to transform ingredients, as they do in beer or cheesemaking), according to a report from the Good Food Institute, a think tank that focuses on alternative proteins.

The most established efforts in this space have been around since the 1980s. They use mycelial fungi, says Adam Leman, principal scientist for fermentation at the Good Food Institute. 

Other startups are starting to grow other options for food products, including Air Protein and Calysta in the US and Solar Foods in Europe, Leman says. LanzaTech, which has significant experience raising microbes and running reactors, hopping into this space is a “really good sign for the industry,” he adds.  

Many alternative protein companies have struggled in recent years—sales of plant-based meat products have dropped, especially in the US. Prices have gone up, and consumers say that alternatives aren’t up to par on taste and texture yet. 

Making food with microbes would use less land and water and produce fewer emissions than many protein sources we rely on today, particularly high-impact ones like beef, Holmgren says. While it’s still early days for bacteria-based foods, one recent review found that mycoprotein-based foods (products like Quorn, made from mycelial fungi) generally have emissions lower than or similar to those of  planet-friendly plant-based protein products, like those produced from corn and soy.

LanzaTech is currently developing prototype products with Mattson, a company that specializes in food development. In one such trial, Mattson made bread using the protein product as a sort of flour, Holmgren says. As for whether the bread tastes good, she says she hasn’t tried it yet, as the company is still working on getting the necessary certification from the US Food and Drug Administration. 

So far, LanzaTech’s efforts have been relatively small-scale—the company is operating a pilot facility in Illinois that can produce around one kilogram of protein product each day. The company is working to start up a pre-commercial plant by 2026 that could produce half a metric ton of product per day, enough to supply the protein requirements of roughly 10,000 people, Holmgren says. A full-scale commercial plant would produce about 45,000 metric tons of protein product each year. 

“I just want to make sure that there’s enough protein for the world,” Holmgren says.