Deciphering Important Odorants in a Spirulina () Dietary Supplement by Aroma Extract Dilution Analysis Using Offline and Online Fractionation Approaches.

Investigating the volatiles isolated from a commercial spirulina () dietary supplement by gas chromatography-olfactometry (GC-O) in combination with an aroma extract dilution analysis (AEDA) resulted in 29 odor events with flavor dilution (FD) factors between 8 and 2048. Identification experiments, including various offline and online fractionation approaches, led to the structure assignment of 30 odorants, among which the most potent were sweaty 2- and 3-methylbutanoic acid (FD 2048), roasty, earthy, shrimp-like 2-ethyl-3,5-dimethylpyrazine (FD 2048), vinegar-like acetic acid (FD 1024), and floral, violet-like β-ionone (FD 1024). Static headspace dilution analysis revealed sulfuric, cabbage-like methanethiol (FD factor ≥ 32) as an additional potent odorant. In summary, 31 important spirulina odorants were identified in this study, and 14 were reported for the first time as spirulina constituents. Our data will provide a basis for future odor optimization of spirulina-based food products.