From Pond to Plate: Tailored Functional Proteins for Next-Gen Microalgal Food.

Climate change, increasing disease pressures, and rising global protein demand challenge future food security and highlight the need for sustainable alternative protein sources. Microalgae have emerged as a promising complementary feedstock due to their rapid growth, high protein content, favorable amino acid profiles, functional properties, and low land requirements. However, despite extensive research progress, industrial scale-up and economic feasibility of microalgal protein production remain limited. This review critically assesses the current state of microalgal protein research across the production chain, including strain selection, cultivation, harvesting, protein extraction, processing, and food applications. While plant-derived protein isolates are already widely used to improve food nutritional and functional properties, microalgal protein isolates remain underexplored in real food matrices, with most applications relying on whole biomass incorporation. Downstream processing represents a major economic bottleneck, particularly for high-purity protein products. The review identifies key knowledge gaps, evaluates socio-economic potential, and highlights limitations in current sustainability assessments. Although microalgae are unlikely to serve as a stand-alone solution to global protein demand, they offer strong potential as a complementary, resource-efficient protein source. Realizing this potential will require interdisciplinary research, improved technoeconomic analyses, supportive regulatory frameworks, and targeted investment to enable industrial implementation and contribute to a more resilient and climate-friendly food system.