The Other Alternative Protein

Algae has long promised a nutrient-dense, low-land alternative protein, but the category has struggled to move beyond niche applications.

Introduction

Algae has long been considered one of the most promising but elusive ingredients in the alternative protein landscape. Its theoretical advantages are undeniable: extremely high protein concentration (50-70% dry weight), rich micronutrient profile (B12, omega-3s, carotenoids), applicability across food categories, and cultivation systems that do not require arable land or freshwater. Despite this, algae struggles to achieve economic viability as a mainstream food ingredient. This deep dive examines the underlying constraints, the commercial progress to date, and the investment opportunities we believe are rational in the current market.

Market Context

The global alternative protein market is projected to reach USD 36.37 billion by 2034 at a CAGR of 8.23%. Within this, algae remains a niche segment but benefits from macro tailwinds:

• Pressure on food manufacturers to reduce synthetic additives and allergens (“clean label”).

• Volatility in crop yields (soy, pea) due to climate shocks.

• Rising consumer demand for nutrient-dense, low-carbon ingredients.

• Growing interest in natural pigments, flavor enhancers and multifunctional ingredients.

These factors create a market pull for algae, but tending to favor specific, high-value use cases.

The Problem: a growing population

The global food system faces a looming protein gap as the world population is expected to peak at around 10.3 billion people by 2080. Conventional livestock and crop-based supply chains are under pressure from climate volatility, land and water constraints, and rising input costs. Livestock alone accounts for almost 60% of food-related greenhouse gas emissions.

In livestock; higher feed, energy, water, fertilizer and labour costs are squeezing farmer margins, often forcing compromises on feed quality (feed alone can account for up to 70% of costs). This cascades into reduced fat and protein content in milk, inherently reducing the quality of downstream products like butter and cheese. This also creates inconsistent meat quality, i.e. inconsistent fat marbling, off flavors, texture issues, all harming consumer satisfaction.

Adding to this pressure, consumers also increasingly prefer “ethically raised”, “grass-fed”, “low carbon” meats, attributes that all cost more to produce and limit scale.

Simultaneously, the dominant plant-based protein supply is vulnerable, relying heavily on monoculture crops such as soy, pea and corn that are acutely susceptible to environmental risks like drought, pests, and long-term soil degradation.

Formulators have struggled to supply nutrient-dense, appealing products that are economically viable to produce, while staying competitive with meat-product protein prices.

Why Algae Hasn’t Broken Through (yet)

Although algae is nutritionally superior to most plant proteins, its production economics remain the bottleneck. Current cost structures across production methods are substantially above commodity protein benchmarks:

Commodity proteins like soy (1-2 EUR/kg) and pea (2-4 EUR/kg) demonstrate the gap algae must close.

Additional barriers include sensory issues (“fishy” flavor), regulatory delays (EU Novel Foods), and consumer unfamiliarity. Competing alternative protein technologies, especially precision fermentation for dairy proteins, are further ahead in both adoption and cost trajectory.

What Algae Can Do Well Today

Despite its challenges, algae excels in several high-margin segments:

• Natural pigments such as phycocyanin (blue spirulina), which already enjoy premium pricing.

• Seafood alternatives, where aroma and pigmentation align better with the category.

• Dairy alternatives, leveraging algae’s emulsification and texture properties.

• Hybrid ingredients, combining protein, color, antioxidants and emulsifying capacity in one input, in turn reducing additive load for formulators.

Crucially, these markets value functionality, clean label status and nutrient density, allowing algae to capture premium pricing without competing directly on cost with soy or pea.

Solutions & Product

Algae offers (in theory): high protein content, complete amino acid profiles and co-benefits such as pigments, emulsification and omega-3 enrichment.

Four core technologies dominate today: open raceway ponds, photobioreactors, heterotrophic fermentation and co-culturing with mycelium.

Open Raceway Ponds:

Open Raceway ponds are shallow, oval-shaped outdoor basins where a single algal strain is grown and circulated by a motorized paddle wheel (see image below). They rely on natural sunlight and ambient temperatures around 20-30^oC.

The paddle wheel ensures homogeneous distribution of biomass and nutrients, while low-cost infrastructure makes this the most common cultivation method globally.

Photobioreactors (PBRs):

Photobioreactors are closed cultivation systems where algae are grown in tubes, flat panels or enclosed geometries, with controlled delivery of lights, CO₂ and nutrients. These allow the algae to photosynthesize for the consistent production of high-purity biomass, pigments and specialized metabolites.

The closed environment drastically reduces contamination risk and allows precise manipulation of process parameters such as temperature, pH and mixing intensity

Heterotrophic Fermentation:

Heterotrophic fermentation grows microalgae in stainless steel fermenters without light, feeding them sugars or other organic carbon sources. This process runs in closed, sterile conditions, enabling 24/7 operation and tight process control similar to conventional microbial fermentation (e.g. yeast or bacteria).

These are highly compatible with existing biomanufacturing infrastructure.

Co-culturing with Mycelium:

Co-culturing combines microalgae with fungal mycelium in a shared bioprocess, where each organism benefits from the other’s metabolites. Algae can act as a nutrient source for mycelium, while the fungal biomass contributes fibrous texture and umami taste.

This is the newest and most experimental technology, where inputs and by-products are recycled in a more closed-loop system, aiming to maximize resource efficiency and functional synergy.

Environmental & Nutritional Impact

Algae cultivation can be decoupled from fertile land and freshwater, using brackish water, wastewater and non-arable sites while capturing CO₂ in the process. Relative to conventional livestock and many crop systems, this allows for lower land intensity.

Overall, if properly executed, algae cultivation offers:

• Minimal land and freshwater use

• Potential for CO₂ capture

• High nutritional density without fortification

• Fewer allergens versus soy/pea

However, the environmental benefit varies strongly by production method. Energy-intensive PBRs or fermenters running on fossil electricity can negate sustainability advantages. Breakthroughs in strain engineering, renewable-powered operations, and process optimization will be essential.

Oyster Bay’s Positioning and Investment Criteria

We do not expect algae to replace commodity plant proteins in the medium term. The economics are too challenging, and consumer adoption is too early.

However, we see real opportunities in the following areas:

Where algae can win:

• Premium functional ingredients rather than bulk protein

• Natural pigments and flavor systems

• Seafood & dairy alternatives where algae’s properties offer a natural fit

• Co-cultured or hybrid systems with defensible IP

What we look for in a fundable algae company:

• A credible cost trajectory toward <5 EUR/kg for the target application

• IP-differentiated cultivation or processing technology; not commodity fermentation

• Strong evidence of clean-label pull from customers

• Realistic regulatory pathway and sensory improvement plan

• Clear go-to-market strategy focusing on premium customers, not retail mass adoption

In short: algae is not a volume replacement for soy or pea. But in the right niches, with the right founders and technology, it could deliver defensible, high-margin ingredients that could play an important role in the future of sustainable protein production.