Solar Foods unveils Solein-powered mayonnaise, filing patent for egg yolk replacement

Solar Foods has developed a mayonnaise formulation using its microbial protein Solein as a complete replacement for egg yolk, a move the Finnish company says could transform one of the world’s most popular condiments. The company has filed a patent application covering the innovation and its production method.

Mayonnaise, traditionally made by emulsifying oil with egg yolk, depends on egg-derived proteins to create a stable emulsion. Solar Foods’ research shows that substituting egg yolk powder with an equivalent amount of Solein can produce around three times more mayonnaise. For food manufacturers, this could mean a direct cost advantage through greater production efficiency, while still delivering the same creamy texture and taste consumers expect.

“The world is getting increasingly unpredictable, and the search for stability has never been greater,” commented Troels Nørgaard, Chief Commercial & Product Officer at Solar Foods. “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.”

Solein is produced via fermentation at Solar Foods’ Factory 01, its first commercial-scale facility. Operating in a continuous process, the site produces around 450 kilograms of Solein daily – equivalent to the protein yield of 50,000 hens. Unlike eggs, which are vulnerable to avian flu outbreaks and seasonal supply cycles, Solein production is stable, scalable, and independent of agricultural constraints.

The facility has an annual capacity of 160 tons, and the production cycle for Solein takes only 70 hours. By decoupling protein production from animal farming, Solar Foods argues that Solein provides food companies with a reliable ingredient stream at steady quality.

The global mayonnaise market is forecast to reach nearly US$13 billion in 2025. At the same time, consumer demand for animal-free and plant-based options is rising, particularly among flexitarians. Solar Foods believes Solein can meet both needs by providing a protein ingredient that is animal-free yet offers the same performance as egg yolk.

Because Solein has strong emulsifying properties, it allows producers to scale mayonnaise production without compromising mouthfeel or creaminess. The neutral flavor profile also creates a versatile base for product innovation, from garlic aioli to chili mayo.

Beyond its functional properties, Solein is positioned as a climate-friendly ingredient. It contains around 80% protein and is also a source of fiber, unsaturated fats, vitamin B12, and iron. Free from cholesterol, gluten, and animal-derived inputs, Solein is both halal and kosher certified.

Solar Foods says its fermentation-based production process requires only a fraction of the land and water of conventional protein sources while generating far fewer emissions. For food companies navigating both consumer expectations and regulatory pressure to cut carbon footprints, Solein could represent a way to make staple products more sustainable.

While mayonnaise is the latest example of Solein’s versatility, Solar Foods is exploring a wide range of uses. The company envisions Solein as a replacement for dairy proteins, egg yolk, and other traditional ingredients in foods such as protein drinks, snacks, ice cream, baked goods, pasta, soups, and sauces.

“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,” Nørgaard said. “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.”

By filing a patent for its Solein-powered mayonnaise, Solar Foods is signaling its intent to move beyond concept development and toward mainstream commercialization. With the ability to cut costs, stabilize supply, and align with sustainability goals, Solein could offer food manufacturers a competitive edge in an industry under increasing pressure to innovate.

For Solar Foods, mayonnaise is not just a condiment—it is a proof point for how microbial proteins can unlock value in everyday foods. If successful, the application could serve as a model for how Solein is integrated into other global staples, from dairy alternatives to convenience meals.