From Fungus to Food: EFSA Greenlights Rhizomucor pusillus Biomass as Safe Novel Ingredient

In a quiet but significant step toward expanding the frontiers of sustainable protein and functional ingredients, the European Food Safety Authority (EFSA) has officially declared microbial biomass from the filamentous fungus Rhizomucor pusillus safe for human consumption—as long as it’s used under clearly defined conditions. The scientific opinion, issued on December 1, 2025, by EFSA’s Panel on Nutrition, Novel Foods and Food Allergens (NDA), clears the way for this unconventional ingredient to enter everything from everyday foods to weight-management meal replacements.

Unlike familiar fungi like yeast or mushrooms, Rhizomucor pusillus is a lesser-known microorganism—yet its dried biomass powder is now stepping into the spotlight as a potential source of high-quality protein, fiber, and bioactive compounds for the future food system. According to the application reviewed under EU Regulation 2015/2283, the novel food is intended for use across multiple categories: as an ingredient in general food products for the entire population, in food supplements for adults over 18 (excluding pregnant and lactating women), and in meal replacements for weight control targeted at adults.

What makes this approval noteworthy is not just the novelty of the source—but the rigor behind the safety assurance. EFSA’s panel scrutinized every aspect: the production process, the chemical composition, stability data, and specifications. Crucially, they found no evidence of genotoxicity, and a 90-day animal study revealed no toxicologically relevant effects even at an extraordinarily high dose of 19,668 mg per kg of body weight per day—far beyond any realistic human intake.

Under the proposed uses, estimated daily consumption ranges from 539 to 1,013 mg/kg body weight, depending on age and product type. When compared to the no-observed-adverse-effect level (NOAEL) from the toxicity study, this yields a margin of exposure (MoE) between 19 and 37 across all population groups—from infants to adults. While regulatory thresholds often seek MoEs above 100 for substances of high concern, EFSA deemed these margins sufficiently protective given the low inherent hazard profile of the biomass.

Equally reassuring is the allergenicity assessment. Despite being a fungal product, the panel concluded that the likelihood of triggering allergic reactions is low, especially since the production process involves thorough drying and standardization that reduces potential allergenic proteins.

This decision reflects a broader shift in food innovation: as the world seeks alternative protein sources with lower environmental footprints, microbial biomass—from fungi, algae, and bacteria—is emerging as a scalable, efficient, and nutritionally promising solution. Rhizomucor pusillus, though obscure to most consumers, joins a growing roster of precision fermentation-derived ingredients gaining regulatory acceptance in Europe.

Importantly, EFSA’s green light comes with clear boundaries: pregnant and breastfeeding women are excluded from supplement use, and all applications must adhere strictly to the proposed usage levels. But within those guardrails, the door is open—for food manufacturers to explore new textures, nutritional boosts, and sustainable formulations, and for consumers to encounter fungi not just on cheese or bread, but as a deliberate, safe, and functional food ingredient.

In the end, EFSA’s message is both scientific and symbolic: the future of food may well be microscopic—and it’s ready for the table.