Quantitative determination and characteristic flavour ofCitrus junos (yuzu) peel oil

Yuzu (Citrus junos Sieb. ex Tanaka) peel oils were extracted by cold-pressing. The flavour components of yuzu were quantitatively determined by use of two internal standards with GC and GC–MS. Characteristic flavour components of yuzu were examined by GC–olfactometry. The contents of hydrocarbons (34 compounds), alcohols (37 compounds) and aldehydes (16 compounds) in weight percent were about 96.55%, 2.03% and 0.1%, respectively. The terpenes were the major components of yuzu peel oil, but they contributed little to the characteristic flavour of yuzu. Methyltrisulfide, borneol, n-octanol, trans-undec-2-enal, (+)-p-mentha-1-en-9-ol, eugenol and carvacrol were found to be strongly involved in the characteristic flavour of yuzu, together with 6-methyl-5-hepten-2-ol and methyltrisulfide having the highest FD-factor.