Algas como fonte alternativa de proteínas e outros nutrientes para a alimentação humana: do cultivo à aplicação

Abstract

The high demand for natural resources, mainly water and productive areas for the manufacture of animal-based products indicates that these resources are inefficient to keep up with the growth of the population. Therefore, alternative sources of nutrients, mainly proteins such as insects, plants and algae can be used for human consumption, minimizing the environmental impacts of food production systems currently adopted. In this context, this review aimed to point out the importance of algae as an alternative source of proteins, gathering information from production to application, highlighting not only the challenges in the sector but also the benefits of cultivation and consumption of algae. It was noted that, in addition to presenting minimal impacts on the environment, algae (microalgae and macroalgae) stand out because they also have high levels of protein (up to ~70%) and other bioactive compounds (such as carotenoids) in their composition, which can positively impact consumers’ health. Microalgae require about twice less water compared to the beef production chain, and almost 1600 hectares less considering the production of 1 ton of Chlorella protein, compared to the same amount of meat. Thus, studies that compile knowledge about the stages of production, processing and beneficiation of algae serve to elucidate the benefits of the production and consumption of this alternative source of protein, helping the dissemination of the sector and attracting investments, either in the scientific field or in the food industry scenario. This work is, therefore, a review that brings information about cultivation and collection of algae; market and production analysis; protein extraction methods; health benefits; industrial applications and regulation aspects. It was noticed that different conditions of cultivation and extraction of compounds must be adopted depending on the industrial aim. Also, it was observed that some of the countries that have more products with algae are also those that produce the most knowledge in the field. Furthermore, the most used species are Arthospira platensis (Spirulina) and Chlorella, which can be explained by their nutritional characteristics, as well as the high digestibility of their biomass. Regarding the nutritional aspects of algae, some studies have associated the presence of polysaccharides, pigments, polyunsaturated fatty acids and peptides with antiproliferative, antioxidant, anti-inflammatory and cardiovascular health effects, respectively. Of the micronutrients, the amounts of vitamin B12, deficient mainly in vegan and vegetarian diets, stands out. Some species of microalgae have up to 100 times more B12 compared to animal products. Finally, despite the potentials highlighted above, some obstacles have been slowing down the growth of the algae market. For example, there are still no specific regulations in the European Union, the United States and Brazil for the production and sale of algae-based foods. Therefore, to guide the sector, only fragments of different documents are taken into account, which is a step back to the development of the algae industry. Considering the different areas of application, algae represent possible advances in the scientific, biotechnological, industrial and health spheres, in a future where sustainability in food production becomes a reality.