Researchers Genetically Enhance Fungus to Taste and Look Like Real Meat

As more people lessen their meat consumption or go vegan, plant-based substitutes have upped their game, creating products that closely mimic the taste and texture of meat. Mycoprotein, an emerging meat alternative made from the mycelium of fermented fungi, has gained popularity in recent years as more brands become accessible to the general public. However, researchers may have found another way to make these substitutes even more appealing and substantially easier to produce by genetically enhancing the edible fungus Aspergillus oryzae.

Lab-grown mushroom meat

Aspergillus oryzae, also known as koji, is a commonly used fungus in East Asia that makes several popular food products like soy sauce, miso, and sake. It is often used as a starter for fermented foods because it enhances their flavor and nutritional content while breaking down their starches. 

Using CRISPR-Cas9 technology, researchers increased the levels of antioxidants and flavor-enhancing molecules in the fungus to make it develop in a more “meat-like” way. The modifications included an increase in ergothioneine, an amino acid and potent antioxidant, and heme, a molecule used by other meat alternatives to give them a more meaty flavor and color. The researchers modified these traits until the koji’s mycelium turned red and became the ideal consistency. These genetic modifications increased the fungus’s desired nutrition and sensory qualities to be used as a meat substitute with minimal processing. 

Advancements in mycoprotein

Mycoprotein production is still in its early stages of development, so it requires more processing to achieve the desired flavor and texture. After traditional mycoprotein is made, it’s mixed with other ingredients to create the end product. In comparison, the genetically modified koji can be grown and then simply shaped into a patty with the same color and taste as ground beef. This streamlined process reduces the need for complex processing, making it a more efficient and potentially more appealing option for creating meat alternatives (1).

What’s next?

Don’t get too excited because this new version of mycoprotein isn’t hitting the grocery store anytime soon. More research will be needed to optimize the fungus’s nutritional value and ensure it’s as similar to meat as possible. Yet this discovery could be the stepping stone into an era of easy-to-produce, highly nutritious, and sustainable meat substitutes. If scientists can find a way to rewrite the genetic code of koji to make it develop similarly to meat, who knows what the future holds for plant-based diets and sustainable food production?

“Humans have already tinkered with the genome and come up with this amazing species,” says Vayu Hill-Maini, a postdoctoral researcher at UC Berkeley and the lead author of the study. “What I want to do is to say, let’s continue that evolution, but let’s bring in our contemporary tools to program it.” 

References

1. Maini Rekdal, Vayu, Casper R. B. van der Luijt, Yan Chen, Ramu Kakumanu, Edward E. K. Baidoo, Christopher J. Petzold, Pablo Cruz-Morales, and Jay D. Keasling. 2024. “Edible Mycelium Bioengineered for Enhanced Nutritional Value and Sensory Appeal Using a Modular Synthetic Biology Toolkit.” Nature Communications 15 (1): 2099. https://doi.org/10.1038/s41467-024-46314-8.