Characterization of the key aroma compounds of Citrus flaviculpus Hort. ex Tanaka by aroma extraction dilution analysis

The key aroma compounds were identified in Citrus flaviculpus Hort. ex Tanaka (ki-mikan) by using aroma extraction dilution analysis (AEDA) and the sniff test. Ki-mikan peel oil was extracted by cold-pressing. The highest flavor dilution (FD) factor was found for limonene. P-Phellandrene, carvacrol, spathulenol, camphene, elemol, (+)-trans-limonene oxide, and tetradecane showed higher relative flavor activity. Results of the sniff test of the original essential oil and its oxygenated fraction revealed that tetradecane, linalool, and alpha-terpineol were regarded as the key aroma compounds of ki-mikan peel oil. A diluted solution of linalool and alpha-terpineol of 3 ppm gave a ki-mikan-like flavor, while a higher concentration near 100 ppm of tetradecane tended to produce a fresh and fruity aroma note similar to ki-mikan flavor.