Abstract:

The aroma components of fresh and heat pump dried samples of daylily were extracted by headspace solid-phase
micro-extraction (HS-SPME) and analyzed by gas chromatography-mass spectrometry (GC-MS). A total of 69 volatile
compounds were identified in both daylily samples, including 48 aroma components in fresh daylily with relative contents
of 99.98% and 43 aroma components in dried daylily with relative content of 99.99%. Twenty-two aroma components were
common to fresh and dried daylily, accounting for 88.61% and 76.73%, respectively. Alcohols, esters and alkanes were
major components. After being dried by heat pump, the relative content of alcohols, aldehydes and esters increased and the
relative content of alkanes decreased substantially accompanied with the disappearance of alkenes and the generation of
ketones in large quantities.

Key words: daylily, heat pump drying, solid-phase micro-extraction, gas chromatography-mass spectrometry (GCMS), aroma components