Do you produce heme by genetic modification?

Yes. We genetically engineer yeast to make a key ingredient: heme. The process allows us to produce the Impossible Burger at scale with the lowest achievable environmental impact.

We start with the gene for a protein called leghemoglobin, a heme protein that is naturally found in the root nodules of soy plants. Leghemoglobin is similar to myoglobin, the heme protein that is exceptionally abundant in animal muscles, binds oxygen and gives meat its unique flavor and aroma.

We add the soy leghemoglobin gene to a yeast strain, and grow the yeast via fermentation. Then we isolate the leghemoglobin, or heme, from the yeast. We add heme to the Impossible Burger to give it the intense, meaty flavor, aroma and cooking properties of animal meat.

By producing our heme in yeast, we avoid digging up soy plants to harvest the root nodules, which would promote erosion and release carbon stored in the soil. This enables us to produce heme sustainably at high volume and make plant-based meat for millions of people, offsetting the environmental impact of animal agriculture.