Research trends and current requirements and challenges in the industrial production of spirulina as a food source

Background: Spirulina was overlooked as a promising future food source until the 1950s. Its industrial production is more recent and still faces various challenges that go beyond the high production costs and the intense "marine" flavour. Despite these challenges, its industrial use is a reality and foods enriched with Spirulina or coloured using Spirulina-derived pigments, are available on the market. Scope and approach: In this review, we discuss overlooked problems faced by Spirulina producers including complex process control, the appearance of algal predators, and environmental impacts. The review also summarises some of the most common uses of Spirulina as a food and as a source of biologically active compounds. Key findings and conclusions: The main use of Spirulina continues to be food production; however, the current trend is to identify novel applications related to health promotion. High production costs and especially its low production capacity continue to limit the development of novel foods. Spirulina is mainly used as a colouring additive or as a part of a marketing strategy. Various human intervention studies suggest its potential use in the prevention of metabolic syndrome. Several strategies are being investigated aimed at reducing costs and water requirement during Spirulina production; producing Spirulina using seawater might also help avoid the appearance of algal predators.