Characterization of the Aroma-active Compounds in Essential Oil and Water Extract of Zanthoxylum bungeanum Pericarp

The essential oil and water extract of Zanthoxylum bungeanum pericarp were produced by steam distillation method. The aroma compounds of essential oil were analyzed by direct injection and the volatiles in water extract of Zanthoxylum bungeanum pericarp were isolated by solvent-assisted flavor evaporation (SAFE). Gas chromatography-mass spectrometry (GC-MS) and gas chromatography-olfactometry (GC-O) were employed to identify the volatile compounds and aroma-active compounds. Results showed that a total of 99 and 153 volatile compounds were identified in the essential oil and water extract, respectively. The lactones and acids were only detected in the water extract. Linalool, D-limonene, terpene, and terpinen-4-ol had the highest concentration in the essential oil and water extract of the green Zanthoxylum bungeanum. Linalool, D-limonene, linalyl acetate, α-myrcene had the highest concentration in the essential oil and water extract of the red Zanthoxylum bungeanum. The total concentration of esters in the essential oil and water extract of red Zanthoxylum bungeanum were higher than that in green Zanthoxylum bungeanum. Sensory evaluation showed the green, sanshoamides-like, and fatty aromas of the essential oil were stronger than those of the water extract, while the sweet, acidic and hala (grease corruption-like) notes of the water extract were stronger than those of the essential oil. In addition, 57 and 68 aroma-active compounds were identified by GC-O in essential oil and water extract, respectively. And the contributions of aroma-active compounds to the aroma profiles were performed by partial least squares regression analysis (PLSR) further. PLSR results showed 29 aroma compounds had significant contribution to aroma profiles of Zanthoxylum bungeanum pericarp essential oil and water extract.