Microalgae (seafood/feed)

01Overview and value chain

Markers: [EC: NACE 03.21 (Marine aquaculture) | OECD: Marine bioeconomy | Regulator: FDA (USA), EFSA (EU), MARA (CN)]

Microalgae are the foundational primary producers of the marine food web, synthesizing the essential omega-3 fatty acids (EPA and DHA) that accumulate in fish. By cultivating microalgae directly—via massive open ponds, closed photobioreactors, or dark heterotrophic fermentation—the aquaculture industry sources these nutrients without relying on wild-caught forage fish (fishmeal and fish oil). Elite strains now accumulate EPA and DHA at 30–50 percent of total lipids, and heterotrophic fermenters exceed 100,000 liters, making algal oil the scalable substitute for fish oil as wild stocks decline and global seafood demand rises.

The key directions of microalgae for aquaculture are:

1. Heterotrophic Fermentation: Sugar-fed strains such as Schizochytrium are grown in dark stainless-steel bioreactors exceeding 100,000 liters, delivering consistent quality and very high omega-3 accumulation — the preferred route to replace fish oil in aquafeed.
2. Autotrophic Open-Pond Cultivation: Sunlight and CO2 drive spirulina and chlorella in raceway ponds, a low-cost legacy process for human supplements and domestic feed.
3. Closed Photobioreactors (PBRs): Sealed PBR systems deliver high-purity, low-contamination biomass at higher capital cost, suited to high-value strains.
4. Aquafeed Integration: Algal oils and meals are formulated into extruded feed pellets, cutting the Fish-In-Fish-Out (FIFO) ratio of salmon and shrimp farming.

Sectoral value chain

[Strain Selection] ──> [Cultivation] ──> [Harvesting] ──> [Extraction]
                              │
                      (Dewatering)
                              │
                              ▼
[Farmed Seafood] <─── [Aquafeed Formulation] <─────┘

Value chain levels

Cross-cutting technologies of the sector:

• Heterotrophic Fermentation: Dark, sugar-fed bioreactors deliver massive scale and high lipid yields independent of sunlight.
• Photobioreactors: Closed systems produce high-purity biomass with tight contamination control.
• Open-Pond Cultivation: Low-CapEx raceway ponds dominate bulk spirulina and chlorella output.

02US

The United States pioneers high-volume heterotrophic fermentation, operating massive facilities that supply the global salmon-farming industry with algal oil.

Heterotrophic fermentation, algal omega-3, spirulina heritage

• Veramaris: Runs large-scale fermentation to produce EPA and DHA algal oils for salmon feed, decoupling aquaculture from wild forage fish.
• Earthrise Nutritionals: A long-established spirulina producer operating open-pond farms for human nutritional supplements.
• Industrial fermentation: US bioreactor capacity anchors the global supply of fermentation-derived omega-3 ingredients.

03CN

China dominates global spirulina and chlorella production in massive open-pond systems, supplying human supplements and domestic aquaculture.

Spirulina scale, open ponds, domestic aquaculture

• Yunnan GreenA: Operates large-scale open-pond spirulina facilities, among the world’s biggest microalgae production sites.
• Chlorella capacity: Domestic growers expand chlorella output for both nutraceutical and aquafeed markets.
• Inland cultivation: Favorable climate and land enable inland open-pond clusters at industrial scale.

04EU

Europe is a driving force in aquafeed sustainability, where feed giants and biotech firms integrate microalgae to cut the FIFO ratio of salmon farming.

Aquafeed sustainability, AlgaPrime DHA, photobioreactors

• Corbion: Produces AlgaPrime DHA through heterotrophic fermentation, a leading algal omega-3 ingredient for salmon feed.
• BioMar Group: Aggressively formulates microalgae into sustainable aquafeed to reduce reliance on wild fish oil.
• AlgaEnergy & Necton: Advance photobioreactor and open-pond microalgae cultivation for nutrition and specialty ingredients.

05Leading companies and research institutes

06Tech stack and innovations

Cultivation technologies are bifurcated into autotrophic (sunlight-driven) and heterotrophic (sugar-fed) systems, each with distinct economics and end markets.

1. Heterotrophic Fermentation:
   • Sugar-fed strains like Schizochytrium grow in dark stainless-steel bioreactors exceeding 100,000 liters, accumulating EPA and DHA at 30–50 percent of total lipids.
   • Delivers consistent quality and the scale needed to replace fish oil in commodity aquafeed.
2. Autotrophic Open Ponds:
   • Sunlight and CO2 drive raceway ponds for spirulina and chlorella, cheap to build but prone to contamination and lower yields.
   • The legacy workhorse for human nutraceutical supplements and emerging domestic feed.
3. Closed Photobioreactors (PBRs):
   • Sealed transparent systems deliver high-purity, contamination-free biomass with tight process control.
   • Higher capital cost is justified for high-value strains and pristine nutritional output.

07Value chains and production pipelines

Industrial pipeline of microalgae-to-aquafeed production (FIFO / aquafeed sustainability standards)

┌───────────────────────────┐      ┌───────────────────────────┐
│ 1. Strain Screening       │ ───> │ 2. Upstream Cultivation   │
└───────────────────────────┘      └───────────────────────────┘
                                                 │
                                                 ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 4. Lipid Extraction       │ <─── │ 3. Harvesting & Dewatering│
└───────────────────────────┘      └───────────────────────────┘
              │
              ▼
┌───────────────────────────┐      ┌───────────────────────────┐
│ 5. Aquafeed Formulation   │ ───> │ 6. Aquaculture Integration│
└───────────────────────────┘      └───────────────────────────┘

Stage 1: Strain screening

Marine microalgae with naturally high EPA/DHA profiles are isolated and characterized, selecting elite strains whose lipids reach 30–50 percent omega-3 content.

Stage 2: Upstream cultivation

Strains are scaled under optimal autotrophic (sunlight/CO2) or heterotrophic (sugar-fed) conditions in ponds, photobioreactors, or dark fermenters.

Stage 3: Harvesting & dewatering

Dilute microalgal broth is concentrated into algal paste — an energy-intensive step that remains the main economic barrier for autotrophic systems.

Stage 4: Lipid extraction

Omega-3 lipids and proteins are isolated from the paste, with oxidative stability during downstream processing a constant technical focus.

Stage 5: Aquafeed formulation

Algal oils and meals are blended into extruded feed pellets that replace wild fish oil, directly lowering the FIFO ratio of salmon and shrimp farming.

Stage 6: Aquaculture integration

Formulated feed is deployed across salmon, shrimp, and other farms, with farmed seafood increasingly marketed as “ocean-safe” or “zero marine ingredient” — pointing toward a circular marine bioeconomy fed by next-generation cellulosic or upcycled feedstocks.