Determination of Volatile Components in Lemon Peels at different ripe stages

Volatiles are important components determining fruit flavor and consumer preferences, and also essential indicators affecting the industrial processing value of fruits. Volatiles in peels of meyer lemon and rough lemon at five harvest stages were characterized through headspace solid-phase microextraction combined with gas chromatography mass spectrometry. 68 volatiles were identified including seven chemical sorts. Among them fifty-one significant varied with fruit ripening.Monoterpenes increased while sesquiterpenes decreased with fruit ripening. D-limonene and wasβ-bisabolene the most riched monoterpene and sesquiterpene respectly.Among oxygenated volatile compounds, aldehydes, alcohols, and others were much abundant than esters and ketones,which in two cultivars generallly decreased with fruit ripenging. Thymol and α-terpineol were the most aboudant oxygenated volatiles in meyer lemon and rough lemon respectively, both of them reached the highest level at first harvest period.Meyer lemon peels especially the immature one was a good raw material for extracting thymol which is an important food spices.