To achieve the triple purpose of enhancing lutein and protein contents as well as improving organoleptic properties in biomass of Auxenochlorella pyrenoidosa mutant as raw material of future food, a novel yellow mutant, CX41 strain, was successfully selected through atmospheric and room temperature plasma (ARTP) mutagenesis and norflurazon-based screening. CX41 strain exhibited a significantly increased lutein (0.86 mg/g) and protein (49.00 % DW) contents simultaneously, while higher levels of total (33.47 % DW) and essential amino acids (14.78 % DW) were achieved with higher amino acid score (86.49) than that of the original A4-1 strain, a yellow and high protein mutant bred previously. Sensory evaluation showed that CX41 biomass has more comparable to A4-1, while in comparison to the wild type (WT), it has a more inclination towards roasted, with a fainter grassy, woody, rancid and fishy odor, and a significant improvement in taste is reflected by a decrease of 8.40 % in sweetness, a reduction of 14.86 % in bitterness, and an increase of 5.93 % in umami intensity. Metabolome analysis revealed that the superior sensory profile was due to the significantly reduced relative odor activity of β-ionone (herbaceous odor) and substances such as 1-octene, hexanal, 1-octen-3-ol, and heptanal (fishy and rancid odors). The extensive enhancements demonstrated CX41 biomass as a highly promising raw material with high nutrients of lutein and protein as well as excellent taste and flavor for future food application.
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