Characterization of the Key Aroma Compounds in Chinese Syrah Wine by Gas Chromatography-Olfactometry-Mass Spectrometry and Aroma Reconstitution Studies.

Pengtao Zhao,Jinxin Gao,Hua Li,Michael Qian

doi:10.3390/molecules22071045

Abstract

The key aroma compounds and the organoleptic quality of two Chinese Syrah wines from the Yunnan Shangri-La region and Ningxia Helan mountain region were characterized. The most important eighty aroma-active compounds were identified by Gas Chromatography-Olfactometry. In both Syrah samples, ethyl 2-methylpropanoate, ethyl 3-methylbutanoate, 3-methylbutyl acetate, 2- and 3-methyl-1-butanol, ethyl hexanoate, ethyl octanoate, 2-phenethyl acetate, methional, 3-methylbutanoic acid, hexanoic acid, octanoic acid, β-damascenone, guaiacol, 2-phenylethanol, trans-whiskylactone, 4-ethylguaiacol, eugenol, 4-ethylphenol, and sotolon were detected to have the highest odor intensities. In the chemical analysis, 72 compounds were quantitated by Stir Bar Sorptive Extraction combined with Gas Chromatography Mass Spectrometry. Based on the Odor Activity Value (OAV), the aromas were reconstituted by combining aroma compounds in the synthetic wine, and sensory descriptive analysis was used to verify the chemical data. Fatty acid ethyl esters, acetate esters, and β-damascenone were found with higher OAVs in the more fruity-smelling sample of Helan Mountain rather than Shangri-La.

Highlights

Wine aroma characteristics originate from grape berries, wine fermentation, and aging techniques [1,2]
In the gas chromatography-olfactometry (GC-O) study, the odorants in the extracts were described as fruity, floral, green, spicy, tobacco, woody, potato, nutty, herb, brandy, sweaty, and so on
3-methyl-1-butanol, ethyl hexanoate, ethyl octanoate, 2-phenethyl acetate, methional, 3-methylbutanoic acid, hexanoic acid, octanoic acid, β-damascenone, guaiacol, 2-phenylethanol, trans-whiskylactone, 4-ethylguaiacol, eugenol, 4-ethylphenol, and sotolon were detected as the most significant aroma compounds in the GC-O analysis. β-Damascenone, ethyl octanoate, acetaldehyde, ethyl isovalerate, ethyl hexanoate, ethyl isobutyrate, isoamyl acetate, butanoic acid, 2- and 3-methylbutyric acid, hexanoic acid, and octanoic acid with high Odor Activity Value (OAV) were detected as the most significant aroma contributors in the SBSE-GC-MS analysis

Summary

Introduction

Wine aroma characteristics originate from grape berries, wine fermentation, and aging techniques [1,2]. High contributing aroma-active volatiles in wine include alcohols, esters, fatty acids, ketones, terpenes, phenols, and aldehydes. They exist in varying concentrations, from 10−12 to 10−4 g/L [4,5]. Solid Phase Extraction (SPE) based on LiChrolut-EN is a fast and user friendly technique that has been widely utilized to isolate and concentrate volatile compounds in wine [10]. This technique concentrates and purifies the analytes by adsorbing the compounds onto the resin bed and recovering them using a small volume of suitable solvents [11].

Methods

Results

Conclusion