Identification of the key aroma-active compounds in wolfberry (Lycium barbarum L.) pulp

Identifying the key aroma-active compounds in wolfberry pulp is essential for ensuring product quality. In this study, the key odorants in fresh wolfberry pulp (FWP), dried wolfberry pulp (DWP) and mixed wolfberry pulp (MWP) were systematically characterized using sensory evaluation, comprehensive two-dimensional gas chromatography and time-of-flight mass spectrometry (GC × GC-TOFMS), gas chromatography-mass spectrometer-olfactometry (GC-MS-O), and headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS). A total of 58 odorants were detected across the three samples, exhibiting flavor dilution (FD) factors ranging from 1 to 243, while 33 odorants showed odor activity values (OAVs) greater than 1. Data analysis identified hexanal, (E)-2-hexenal, geranylacetone, 2-undecanone, 6-methyl-5-hepten-2-one, 1-hexanol, 4-hexen-1-ol, 2-hexen-1-ol, 2-pentylfuran, eremophilene, and β-selinene as the key aroma-active compounds in FWP. Furthermore, HS-GC-IMS provided distinctive fingerprint profiles that allowed clear differentiation of 84 odorants among FWP, DWP, and MWP. These findings establish a theoretical basis for the quality control and improvement of wolfberry pulp products.