Sensory attributes and volatile compounds characteristics of Zanthoxylum genus

Abstract

A lexicon was developed to describe the aroma and flavor profiles of sensory characteristics of Zanthoxylum bungeanum, also known as Sichuan pepper. As a further investigation, an instrumental analysis was conducted in order to identify the volatile compounds of Sichuan pepper. For the sensory lexicon, a highly trained descriptive analysis panel was used to characterize the aroma and flavor characteristics for Sichuan Pepper. A total of 32 sensory attributes were detected which included 15 attributes for aroma profile and 17 attributes for flavor profile. The aroma profile included peppery, green, citrus, pungent, fennel anise, brothy, floral perfumery, piney, woody, fruity, sweet aromatics, petroleum-like, chive, earthy, brown, smoke and menthol. The flavor profile included green, citrus, minty, fruity, pepper, petroleum-like, floral, cardboard, green viney, pungent, umami, earthy, piney, sweet, bitter, astringent, tingle, and numbing. The lexicon was used to characterize 16 different Sichuan pepper, including subspecies, locations, and brands, which showed that the lexicon could effectively differentiate among samples. Differences in the peppers were analyzed by analysis of variance (ANOVA) and principal components analysis. Gas chromatography-mass spectrometry (GC-MS) associated with a modified headspace solid-phase microextraction was used for to characterize the volatile fractions of the 16 Sichuan Pepper samples to differentiate green and red Sichuan peppers. A total of 99 volatile compounds were tentatively detected among 16 samples. The 46 terpenoid compounds detected were the most abundant volatile compounds. Partial least squares regression was used to associate descriptive sensory characteristics to volatile compounds. Possible relationships between volatile compounds and sensory attributes were detected, in which the most prominent associations included β-Copaene related to Anise/Fennel aroma and Fruity flavor,α-Phellandrene related to Earthy aroma, cis-Carveol and 2-Phenylethyl acetate related to Perfumery/Floral aroma, Sabinene hydrate related to Woody aroma and Petroleum-Like flavor, (+)-β-Thujone related to Anise/Fennel aroma, Fruity aroma, Woody aroma, Green flavor, Petroleum-Like flavor, Green Viney flavor, Pungent flavor, and Bitter flavor, β-Pinene related to Citrus flavor, Caryophyllene related to Anise/Fennel aroma, δ-Limonene related to Menthol aroma, Linalyl acetate related to Pepper aroma, Fruity aroma and Citrus flavor, β-Selinene related to Pepper flavor and Petroleum-Like flavor. Results suggested age would be an important factor to differentiate Sichuan peppers.