Better Meat Co Secures Patent for Turning Potato Waste into Mycelium Protein

California-based food tech company The Better Meat Co has received its sixth US patent, this time for a method of growing mycelium protein on potato-processing sidestreams. The new patent expands on previous intellectual property by covering production processes using both Neurospora and Aspergillus species, as well as downstream applications from pasteurisation to shaping into meat analogues.

Image courtesy: The Better Meat Co

From Potato Scrap to Protein Source

The fermentation process uses liquid potato waste—such as off-cuts, sub-sized potatoes, or fries rejected for not meeting length requirements—as a carbon source. These sidestreams are sourced through a partnership with a major potato processor, giving The Better Meat Co access to what CEO Paul Shapiro calls a “nearly unlimited” supply. In just hours, low-value starches are converted into protein-rich mycelium.

Image courtesy: The Better Meat Co

The result, known commercially as Rhiza, is a whole-biomass mycoprotein with 50% protein content by dry weight, a protein digestibility score of 0.87–0.96, and zero cholesterol or saturated fat. Unlike many plant proteins, Rhiza contains all essential amino acids and is high in both fibre and micronutrients like selenium and copper.

From Lab Bench to Market

The company has now signed five agreements with large meat producers across North America, Asia, and South America—including a letter of intent with one of the region’s largest meat firms. Collectively, these deals could generate $13 million in annual revenue. To meet demand, The Better Meat Co is shifting from its 9,000-litre pilot facility to contract manufacturing at 150,000-litre scale.

According to Shapiro, this route offers faster scale-up and lower capital expenditure compared to building a full-scale fermentation plant. The firm is also in the midst of a $15 million fundraising round to support its growth, following a $1.5 million grant from the US Department of Defense’s biomanufacturing programme.

Versatility and Tradition

Neurospora crassa, one of the primary fungi used, is already known in food systems around the world. It is used in Indonesian oncom, Brazilian tiquira, and even French Roquefort cheese. The new patent also includes Aspergillus oryzae, a staple in fermented foods like miso and sake.

Image courtesy: The Better Meat Co

Beyond the upstream fermentation, the patent also covers steps for blending the mycelium with other ingredients and shaping it into nuggets, sausages, and patties. Rhiza has already received GRAS (Generally Recognized as Safe) status from the US FDA and USDA, as well as the Singapore Food Agency.

The Bigger Picture

This latest milestone reinforces The Better Meat Co’s position in the microbial protein space, where it sits alongside other fermentation startups like Meati, Planted, and MyForest Foods. TIME Magazine recently named it one of the World’s Top GreenTech Companies of 2025.

With a process that uses industrial food waste to produce nutrient-dense protein, the company exemplifies how fungi can support both food security and waste valorisation. As Shapiro puts it: “We can turn discarded carbohydrates into high-value protein in less than a day.”