From ocean to table: Seaweed as a nutrient-dense, health-promoting and sustainable protein source

The increasing demand for sustainable protein sources globally has created a need for alternative conventional protein sources that are causing environmental degradation. Seaweeds, traditionally used as food items in East Asian countries, are found to be nutrient-rich, climate friendly foods with high protein content, amino acids, and bioactive compounds. The present review critically synthesized the existing knowledge on seaweed proteins, with emphasis on variability, seasonal and regional factors, and methodological challenges. Red and green seaweed proteins are found to possess high levels of proteins comparable to conventional food items, with functional proteins that possess antioxidant, anti-inflammatory, and nutraceutical properties. Seaweed proteins such as phycobiliproteins, glycoproteins, and lectins possess techno-functional properties that can be used as food, pharmaceutical, and cosmetics. The limitations associated with the digestibility of seaweed proteins due to complex cell walls and antinutritional factors require advanced processing techniques. The review also covers the limitation in the traditional nitrogen-to-protein conversion factors, suggesting the need for standards techniques specifically for seaweed to ensure the nutritional assessment process is accurate. This article covers the aspects of protein diversity, digestibility, techno-functional properties, health benefits, and sustainability. It offers a comprehensive platform to advance seaweed proteins from research to mainstream food system to support global food security and environmental sustainability. This research contributes to the Sustainable Development Goals (SDGs), particularly SDG 2, SDG 8, SDG 12, and SDG 14.