Rapid discrimination of Citrus reticulata 'Chachi' by headspace-gas chromatography-ion mobility spectrometry fingerprints combined with principal component analysis

Dried pericarps of Citrus reticulata 'Chachi', named Guangchenpi (GCP), have been used as both food and medicine in China for centuries. Due to its special flavour and taste, the price of GCP is much higher than those of dried pericarps from other Citrus reticulata Blanco varieties (collectively called Chenpi, CP). Therefore, some CP have been disguised has GCP by dishonest businessmen to obtain a higher profit. In this study, a simple, rapid, effective and economic analytical method based on headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS) was established to discriminate GCP and CP by their volatile organic compounds (VOCs). Principal component analysis (PCA) was performed to extract meaningful attributes from VOCs based on the GC-IMS chromatograms and to give the analysis results. Twelve, 12 and 14 markers were identified and established as the characteristic fingerprints of GCP analysis of 45 batches of samples via SE-54, OV-1701 and Inter Cap WAX gas chromatographic columns, respectively. The PCA results indicated that GCP and CP could be effectively discriminated. This study confirmed the potential of HS-GC-IMS combined with PCA as a reliable analytical screening technique to discriminate between GCP and CP.