From food innovation to sustainability, algae are gaining prominence as a functional ingredient capable of creating economic value, responding to new consumer trends, and contributing to the Sustainable Development Goals.

Algae are much more than a niche food ingredient in Portugal; they represent a promising and sustainable solution for the future of food. Although their presence in our cuisine is still modest, the growing interest in natural and healthy products, driven by globalization and new trends, points to a food revolution in which algae can play a prominent role.

According to the World Health Organization, more than 821 million people worldwide suffer from malnutrition due to protein-deficient diets, which has led to a significant increase in demand for food sources rich in this nutrient. Algae stand out as true reservoirs of bioactive compounds, including proteins, which can represent about 30% of their composition, reaching 55 to 60% in some cyanobacteria.

Algae can be categorized into macroalgae and microalgae, each offering distinct biochemical profiles and cultivation strategies. Macroalgae, such as Ulva lactuca (sea lettuce), Porphyra spp. (nori), Undaria pinnatifida (wakame), and Himanthalia elongata (sea spaghetti), are traditionally harvested or cultivated in coastal marine environments. Microalgae, including Chlorella vulgaris and Arthrospira platensis (known as spirulina), are typically cultivated in controlled systems, which allows for more consistent and large-scale production.

From a nutritional standpoint, spirulina is a notable example, with a protein content of up to 64.7 g/100 g dry weight, according to Peñalver et al. (2024). Other macroalgae, such as nori and wakame, also have significant protein levels. It is important to note that Spirulina also has a remarkable lipid content (5.13 g/100 g) rich in polyunsaturated fatty acids (PUFAs), which reinforce its health benefits.

According to Bhatnagar et al. (2024), algae offer distinct advantages over traditional protein sources. They have a higher growth rate and photosynthetic potential, do not compete for large areas of arable land, require less water, and have carbon sequestration capacity. Because they do not require fertile soil, fresh water, or chemicals and are highly productive, algae offer an efficient and sustainable alternative to pressures on terrestrial resources. For example, the land required for commercial algae production is less than 2.5 m²/kg of protein, compared to 144 to 258 m²/kg for beef and 42 to 52 m²/kg for chicken. These characteristics make them a promising and sustainable option for the food industry.

Thus, algae are a promising solution to address global challenges linked to the SDGs, especially in the areas of food security (SDG 2), sustainable consumption and production (SDG 12), and climate action (SDG 13). In addition, they contribute to carbon capture and water quality improvement, reinforcing their potential in the transition to a regenerative blue bioeconomy.

Algae can be incorporated into a wide range of food products to improve their nutritional quality. Currently, they are being tested as an ingredient in bread, pasta, cookies, and dairy products such as cheese and yogurt. The addition of this biomass can increase the protein and mineral content of these products (Bhatnagar et al., 2024). In addition, extracts such as agar-agar, obtained from red algae (mainly Gelidium sesquipedale), are beginning to be used as a natural gelling agent, serving as a superior vegan alternative to animal gelatin. According to Bojorges et al. (2025), brown algae extracts can also act as emulsifiers, helping to mix ingredients in recipes.

However, it is important to recognize the challenges. Some algae have a rigid cell wall that makes protein extraction difficult. In addition, intense flavor and odor, as well as color changes, can hinder consumer acceptance. However, these obstacles can be overcome. I believe that optimizing concentrations and exploring new extraction methods, such as microwave- or ultrasound-assisted extraction, are the way forward to obtain high-quality extracts that eliminate sensory disadvantages.

In short, algae have the potential to establish themselves as a pillar of a new food era. Due to their versatility, nutritional richness, and ability to regenerate ecosystems, they can profoundly transform the way we produce and consume, paving the way for a more sustainable, resilient food system that is in harmony with the planet.

It is in our hands to turn this potential into action, making algae the foundation of a truly sustainable food future!