Using a method
called static
headspace — multi-capillary column — gas chromatography — ion mobility spectrometry (SHS - MCC - GC - IMS), the team identified six main VOCs contributing to the smell: butyric acid (strong, rancid butter - like odor), dimethyl disulfide (unpleasant, onion - like odor), dimethyl trisulfide (powerful odor), 2 - heptanone (banana - like fruity odor), 2 - nonanone (fruity, floral, fatty, herbaceous odor) and 2 - octanone (apple - like odor).