Characterization of Qingke Liquor Aroma from Tibet

Abstract

Qingke liquor is a very famous Tibetan alcoholic beverage made from “Qingke”, hull-less highland barley, which is exclusively grown in Qinghai-Tibetan Plateau with an average altitude of 4000 m. Qingke liquor made in such an area whose quality or characteristics is a result of its geographic environment, including natural and human culture. In this study, the aroma compounds in two Qingke liquors made from highland barley grown at different elevations (QKH, high elevation, and QKL, low elevation) were compared by aroma extract dilution analysis (AEDA), aroma intensity (Osme), odor activity values (OAVs, ratio of concentration to odor threshold), and aroma recombination. Results revealed ethyl acetate, ethyl 2-methyl propanoate, ethyl butanoate, ethyl 3-methyl butanoate, ethyl pentanoate, ethyl hexanoate, ethyl octanoate, 3-methylbutanal, 3-methyl-1-butanol, 1-octen-3-ol, β-damascenone, 2,3-butanedione (diacetyl), acetoin, and 2-methoxyphenol (OAV ≥ 10) as important aroma active compounds to Qingke liquors. However, QKH had higher OAVs for most of the compounds than that of QKL. An aroma recombination study confirmed the analysis of aroma-active compounds in Qingke liquor, whereas the aroma emission test demonstrated 3-methylbutanal as the key aroma compound for both Qingke liquors.

Characterization of the Aroma of an Instant White Tea Dried by Freeze Drying

“…AEDA was conducted based on the aforementioned GC-MS-O method with procedures reported in previous literatures [14][15][16]. The SDE extract were gradually diluted in the ratio of 4 (by volume) with n-hexane, followed by GC-MS-O analysis.…”

“…In order to evaluate whether the key aromatic compounds were identified correctly, aroma reconstruction and omission experiments were performed according to the methods reported in the previous literatures with minor modifications [11,14,17]. The aroma reconstruction model of the SDE extract (FM1) was prepared with the 15 aromatic volatiles (except hotrienol) at concentrations measured (Table 1), where n-hexane was used as the matrix, and the final volume was 1.5 mL.…”

“…Aroma characteristic could be evaluated by sensory evaluation [4,[9][10][11] and instrument analysis such as GC-MS determination [8,9,12,13]. In addition, the aroma-active compounds could be determined with olfactometric techniques [14][15][16] and odor active value (OAV) analysis [10,11], as well as confirmation via aroma reconstruction and omission test [11,14,17]. Volatile compounds with concentrations over thresholds could contribute to tea aroma with their respective odors [18], as well as their antagonism and synergism interactions [12].…”

Comparison of Potent Odorants in Traditional and Modern Types of Chinese Xiaoqu Liquor (Baijiu) Based on Odor Activity Values and Multivariate Analyses

“…The results showed that both liquors had a similar aroma profile, but the Osme values varied (Figure 1). Most of these components are well-known odorants in Baijiu [7,17,18], but 36 of them have not been reported in a previous study of xiaoqu Baijiu [13]. Among the 79 aroma compounds, 26 esters, 15 alcohols, 12 aldehydes and ketones, nine acids, six phenols, five terpenoids, four furans, and two sulfur compounds were detected in the M and T samples.…”

Tandem Solid-Phase Extraction Columns for Simultaneous Aroma Extraction and Fractionation of Wuliangye and Other Baijiu

“…Gas chromatography-olfactometry (GC-O) was first used to study the aroma-active compounds in baijiu in 2005 [ 3 ]. Among all the aroma-active compounds identified, fatty acid esters have been proven to be the main contributors to baijiu aroma [ 3 , 4 , 5 , 6 , 7 ], exhibiting fruity and floral notes [ 3 , 4 , 5 , 6 ]. Free fatty acids and alcohols also make important aroma contributions.…”