Comparative evaluation of sensory and instrumental flavor profiles of four edible microalgae: Spirulina platensis, Chlorella pyrenoidosa, Chlamydomonas reinhardtii, and Haematococcus pluvialis

Microalgae sensory features are an important parameter to consider in food applications. The current study comparatively evaluated the flavor profiles of four commercial edible microalgae species, i.e., Spirulina platensis, Chlorella proteinosa, Chlamydomonas reinhardtii, and Haematococcus pluvialis through sensory evaluation by a trained expert panel (n = 15) and chemical profiling of flavor compounds, with multivariate statistical methods used to correlate descriptive taste and odor analysis with non-volatile and volatile compounds. S. platensis displayed characteristic salty and umami tastes arising from inorganic ions and 5 '-nucleotides, respectively, as well as "muddy" and "floral" odor attributes mainly associated with sulfur compounds and ketones. C. proteinosa and C. reinhardtii shared the taste attributes of sweetness and bitterness mainly contributed by free amino acids, as well as the odor attributes of "seaweed" and "mushroom" in association with aldehydes and alcohols. H. pluvialis had a typical sour taste owning to the presence of abundant organic acids, and smelled "fatty", "phenolic", "licorice", and "fruity" due to aromatic ester and phenolic compounds. Overall, our results provide fundamental insights into the sensory features of common edible microalgae to guide future food applications.