Aroma fingerprinting of 26 finger lime (Citrus australasica) cultivars grown in Japan based on peel voc profiles

Abstract

Peel volatile profiles of 26 finger lime (Citrus australasica) cultivars cultivated in Japan were characterized by GC/FID and GC/MS. Fifty-five volatile organic compounds (VOCs) were identified, spanning monoterpene hydrocarbons, oxygenated monoterpenes, sesquiterpenes and minor oxygenated constituents. Limonene predominated in many cultivars, whereas several secondary monoterpenes, oxygenated monoterpenes and sesquiterpenes showed pronounced cultivar-dependent distributions. No consistent association was observed between vesicle colour and peel VOC composition. Two-dimensional hierarchical clustering and heatmap visualization of cultivar-averaged profiles highlighted coordinated compositional tendencies across major VOC classes and revealed gradual chemotypic transitions. Candidate marker VOCs that differentiate DE and CLT were identified, including cis-2-hexen-1-ol and trans-dihydrocarvone (DE) and geranial (CLT). Because VOC abundances were obtained as GC/FID relative peak areas without an internal standard, the results are interpreted as semi-quantitative. Overall, this work provides a curated reference dataset for comparing Japanese-grown finger lime cultivars and supports cultivar characterization based on aroma-relevant chemical patterning.