AUTHOR=Canelli Greta , Tarnutzer Carmen , Carpine Roberta , Neutsch Lukas , Bolten Christoph J. , Dionisi Fabiola , Mathys Alexander 

TITLE=Biochemical and Nutritional Evaluation of Chlorella and Auxenochlorella Biomasses Relevant for Food Application

JOURNAL=Frontiers in Nutrition

VOLUME=7

YEAR=2020

URL=https://www.frontiersin.org/journals/nutrition/articles/10.3389/fnut.2020.565996

DOI=10.3389/fnut.2020.565996

ISSN=2296-861X

ABSTRACT=<p>Microalgae are a source of potentially healthy and sustainable nutrients. However, the bioaccessibility of these nutrients remains uncertain. In this study, we analyzed the biomass composition of five commercial <italic>Chlorella</italic> and <italic>Auxenochlorella</italic> strains, and <italic>Chlorella vulgaris</italic> heterotrophically cultivated in our laboratory. Protein accounted for 65 ± 3% (w w<sup>−1</sup>) dry matter (DM) in all biomasses, except for the lab-grown <italic>C. vulgaris</italic> that contained 20% (w w<sup>−1</sup>) DM protein. The fatty acids content was comparable and ranged between 7 and 10% (w w<sup>−1</sup>) DM. Most of the biomasses had a ω6-polyunsaturated fatty acids (PUFAs)/ω3-PUFAs ratio &lt;4, as recommended by nutritional experts. A recently published harmonized protocol for <italic>in vitro</italic> digestion was used to evaluate fatty acids and protein bioaccessibilities. Protein bioaccessibility ranged between 60 and 74% for commercial <italic>Chlorella</italic> and <italic>Auxenochlorella</italic> biomasses and was 43% for the lab-grown <italic>C. vulgaris</italic>. Fatty acids bioaccessibility was &lt;7% in commercial biomasses and 19% in the lab-grown <italic>C. vulgaris</italic>. Taken together, the results show that microalgae are promising sources of bioaccessible protein. The limited fatty acids bioaccessibility indicates the need for alternative upstream and downstream production strategies.</p>