Solar Foods has unveiled a new application for its microbial protein Solein, using it as a replacement for egg yolk in mayonnaise production.

The company has filed a patent for the innovation, which it says could deliver cost, efficiency and sustainability advantages to the food industry.

Traditionally, mayonnaise is made by emulsifying oil with egg yolk. Solar Foods claims that replacing egg yolk powder with Solein yields around three times more mayonnaise from the same amount of raw material, while maintaining the same creamy texture and taste. This, the company says, could give food manufacturers a direct cost advantage and reduce reliance on volatile egg markets.

Troels Nørgaard, chief commercial and product officer at Solar Foods, said: “The world is getting increasingly unpredictable, and the search for stability has never been greater. The food industry is looking for ingredients with stable supply, quality, and steady prices, and the demand for sustainability is growing rapidly."

"For example, egg yolk powder prices have fluctuated wildly in recent years. With Solein, companies can lock in multi-year agreements at a fixed price, having more control and de-risking from sudden spikes and market disruptions from disease outbreaks and climate conditions to geopolitical upheavals."

Produced through fermentation, Solein is independent of farming cycles and can be manufactured year-round. Solar Foods’ first commercial facility, Factory 01, has a capacity of 160 tons annually, equivalent to about 450 kg per day—an output the company says would otherwise require 50,000 hens to match in egg protein.

Beyond its emulsifying properties, Solein is marketed as a highly versatile protein source. It is around 80% protein, contains vitamin B12 and iron and is gluten-free, cholesterol-free, halal and kosher-certified. Solar Foods sees potential applications not only in condiments, but also in categories such as dairy alternatives, baked goods, protein drinks, ice cream and soups.

The global mayonnaise market is forecast to reach nearly $13 billion by 2025, with demand for animal-free alternatives expected to rise. Solar Foods positions Solein as a climate-friendly option, requiring only a fraction of the land, water and emissions of traditional proteins.

Nørgaard added: “Solein excels as an ingredient in different health and performance nutrition products, but beyond that, we see Solein playing a pivotal role in transforming global food systems. When we talk about feeding 10 billion people, Solein’s unmatched value becomes a key advantage in all imaginable food categories – Solein’s journey is just beginning."