Microalgal protein for sustainable and nutritious foods: A joint analysis of environmental impacts, health benefits and consumer's acceptance

Background: Food sources with high productivity and low environmental impact can alleviate or even overcome the pressure of the growing global population and deteriorating climate. Microalgal proteins are promising alternatives to impel a win-win diet structure, but joint analyses of environmental impacts, health benefits, and consumer's acceptance are seldom available. Scope and approach: Herein, we propose the feasibility of using microalgal protein for nutritious and sustainable foods driven by developing technologies and future food systems. The major barriers in the economic viability of protein production, tailored nutrients, and acceptable organoleptic traits are discussed to realize this expectation. Key findings and conclusions: The sustainable production of microalgal protein is specific context based on cultivation modes and strategies. The high-density cultivation of microalgae provides three orders of magnitude of protein productivity than traditional crops but produces more greenhouse gas. A potential conflict exists between greenhouse-gas emissions and the utilization of land and freshwater resources. The in situ high-density concept by regulating carbon and nitrogen metabolism holds promise for improving protein production while mitigating environmental impacts. In addition, microalgal proteins are nutritious to substitute red meat by overcoming several nutritional deficiencies. Consumer acceptance influences microalgal production, and then efficient strategies and novel technologies are proposed to overcome barriers in this process. Our findings support an integrated system involving stakeholders to further develop microalgal protein for sustainable and nutritious foods.