Study on the Quality Components Differences Among Tea Cultivars in Northern Guizhou

Manman Gao; Kai Zhang; Huan Wang; Heng Sun

doi:10.20944/preprints202607.2050.v1

Submitted:

27 July 2026

Posted:

28 July 2026

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Abstract

This study investigated the quality characteristics of tea plant germplasm from different geographic origins under the ecological conditions of Guizhou. Quality components and volatile aroma compounds were analyzed in four introduced cultivars (CC4H, SLX, SMCY, HJC1) and two local cultivars (QM601, GZSC). The results showed that the phenol-to-amine ratios of all six cultivars were below 8, indicating their suitability for green tea production. GC-MS identified a total of 147 volatile compounds, among which alcohols were present in the highest concentrations (1090.69–1499.18 μg/kg). SMCY had the highest total alcohol content. ROAV analysis confirmed that benzaldehyde, (E)-β-damascone, β-ionone, and 1-octene-3-one are the key contributors to the aroma profile. Among the introduced cultivars, SMCY stands out for its floral and aromatic compounds; SLX is notably rich in floral and fruity aldehydes and esters; CC4H has a distinct roasted sweetness, and HJC1 offers the best freshness. The local variety QM601 exhibits synergistic accumulation of tea polyphenols and fruity terpenes, while GZSC maintains its traditional advantage in the balance of phenolic and amino compounds. These findings provide a theoretical basis for the differentiated deployment of tea cultivars in Guizhou’s tea-growing regions.

Keywords:

tea cultivars

;

quality components

;

volatile aromatic compounds

;

ROAV

Subject:

Biology and Life Sciences - Food Science and Technology

1. Introduction

The tea plant (Camellia sinensis L.O. Kuntze) is a perennial specialty cash crop whose quality characteristics results from the synergistic interplay between genetic background and cultivation environment [1]. Among these, the germplasm genotype underpins the baseline abundance and compositional architecture of secondary metabolites, thereby directly governing the biosynthetic capacity for critical flavor precursors, including amino acids, tea polyphenols, and catechins.[2]. Meanwhile, regional ecological factors—including altitude, light intensity, temperature, and humidity, and soil physicochemical characteristics—modulate the metabolic rhythms within tea plants, reshape the proportional accumulation of metabolites, and ultimately give rise to diverse sensory flavor profiles among cultivars and production areas. [3,4,5,6,7]. This genotype–environment interaction implies that, upon introduction of geographically distinct cultivars to a common ecological region, the extent of quality-component divergence is governed both by the cultivars’ intrinsic metabolic capacity and by the remodeling of their pre-existing metabolic pathways imposed by the novel environment.

As a prime example of high-altitude, premium tea-growing regions in southwest China, Guizhou’s unique natural environment—characterized by “high altitude, limited sunlight, frequent fog, and a pristine ecosystem”—endows its tea with quality advantages such as high amino acid content, a balanced phenolic-to-amino acid ratio, and a delicate yet rich aroma [8]. The abundant local tea plant genetic resources within the province serve as the core genetic foundation supporting the high-quality development and differentiated competitiveness of Guizhou’s tea industry. In order to broaden the genetic diversity of tea plant resources, optimize product flavor profiles, and meet diverse market demands, a large number of high-quality tea plant germplasms from outside the province have been introduced to Guizhou in recent years for local cultivation and domestication. However, after any plant cultivar is introduced into a new environment, its physiological metabolism and quality traits must undergo a long-term adaptive remodeling in response to specific ecological factors [9,10]. To date, there has been a lack of systematic comparative research on the quality domestication characteristics exhibited by tea plant germplasm from different geographical origins under typical ecological conditions in Guizhou, as well as on the mechanisms underlying the formation of quality differences between these germplasm sources and Guizhou’s native superior germplasm.

This study examined four tea cultivars sourced from different provinces outside Guizhou, using two major tea cultivars grown locally in Guizhou as controls. Under strictly standardized cultivation management and field conditions, the study systematically measured key quality indicators—including free amino acids, tea polyphenols, water-soluble extracts, and volatile aromatic compounds—in each tea cultivar. By further integrating multivariate statistical and variance analysis methods, we will conduct an in-depth analysis of the quality phenotypic differences among different germplasm accessions, with the aim of revealing the quality reshaping characteristics of exogenous tea cultivars following their domestication and adaptation to Guizhou’s unique ecological conditions, identify the key points of quality advantages and flavor differences between exogenous and local germplasm, and provide a solid theoretical basis and practical guidance for the innovative utilization of tea germplasm resources in Guizhou’s tea-growing regions, the optimization and enhancement of high-quality and efficient cultivation techniques, and the targeted development of distinctive flavored tea products.

2. Materials and Methods

2.1. Main Chemicals

The main chemicals used in this study included ninhydrin (AR, Shanghai Haohong Biomedical Technology Co., Ltd.); Folin-Ciocalteu (biotechnology grade, Shanghai Eanchen Chemical Technology Co., Ltd.); L-theanine (standard products, Shanghai Eanchen Chemical Technology Co., Ltd.); Tea polyphenol (standard products, Shanghai Eanchen Chemical Technology Co., Ltd.).

The 20 mL headspace vials, which come with 18 mm magnetic PTFE/silicone caps, were acquired from Agilent Technologies Inc. (Palo Alto, CA, USA). For headspace solid-phase microextraction (HS-SPME), the manual holder and divinylbenzene/carbon wide range/polydimethylsiloxane (DVB/CWR/PDMS) fiber assembly were sourced from Supelco (Belle fonte, PA, USA).

2.2. Plant Materials

In this study, the six tea cultivars (HJC 1, CC4H, JZSC, QM601, SLX and SMCY) tested were planted at the Egongba Tea Germplasm Repository in Xinglong Town, Meitan County, Zunyi City, Guizhou Province, and all the tea trees were 4 years old.

2.3. Characterization of Tea Samples

Fresh tender tea shoots (one bud and one leaf) were collected in the early spring before the Qingming Festival. All samples were dried to constant weight in an oven at 103 °C, pulverized, and sieved through a 60-mesh screen for subsequent determination.

The contents of tea polyphenols were determined via the spectrophotometric method specified in GB/T 8313-2018 (Determination of tea polyphenols and catechins in tea) [11]. The total free amino acid content was measured using the spectrophotometric method described in GB/T 8314-2013 (Tea - Determination of total free amino acids) [12]. The water extract content was determined in accordance with the standard method of GB/T 8305-2013 (Tea- Determination of water extracts) [13].

The ratio of tea polyphenols to free amino acids (phenol-amino ratio) was calculated as follows: phenol-amino ratio = tea polyphenol content / total free amino acid content. All the above experiments were repeated 3 times.

2.4. Analysis of Volatile Metabolites in Tea Samples Based on HS-SPME-GC/MS

2.4.1. Headspace Solid-Phase Microextraction Conditions

Exactly 1.0 g of tea powder was accurately weighed into a 20 mL headspace vial, followed by the addition of 2.5 µL of internal standard (n-pentadecane-d32, 50 µg/mL) and 4 mL of saturated sodium chloride aqueous solution. The sample was equilibrated at 80 °C and 500 rpm for 20 min. Extraction was then carried out using a 120 µm DVB/CWR/PDMS solid-phase microextraction fiber at 80 °C and 500 rpm for 10 min. After extraction, the fiber was desorbed at 250 °C for 5 min.

2.4.2. Chromatographic and Mass Spectrometry Conditions

A VF-WAXms column (25 m × 0.25 mm × 0.2 µm, Agilent CP9204) was employed. The injector temperature was 240 °C. The carrier gas was high-purity helium at 1.0 mL/min, with a septum purge flow of 3 mL/min. The oven temperature was programmed from 40 °C to 120 °C at 8 °C/min, then to 230 °C at 20 °C/min, and held for 4.5 min, for a total run time of 20 min. Mass spectrometry was carried out in full-scan mode (m/z 35–500) using an EI ionization source. The ion source temperature was maintained at 250 ◦C, and the electron energy was 70 eV.

2.4.3. Qualitative and Quantitative Methods for Volatile Compounds

Volatile compounds were identified by comparing the calculated retention indices (RI, determined from n-alkanes C8-C30) with those in the standard mass spectra database (NIST-2023, GC-Orbitrap flavor and fragrances v1.0). Quantification was carried out based on the peak area of internal standard compounds.

2.4.4. Relative Odor Activity Value

The relative odor activity value (ROAV) was employed to evaluate the contribution of each volatile compound to the overall tea aroma of the tea. Based on quantitative analysis of volatile compounds, the flavor thresholds of volatile components in references were consulted, and ROAV of volatile components were calculated according to formula [14]:

ROAV = RCi / OTi

where RCi is the relative content of volatile compounds, μg/kg; OTi is the aroma threshold of volatile compounds, μg/kg.

2.5. Statistical Analysis

Volatile compound data were analyzed using Excel 2024 software, with results presented as ‘mean ± standard deviation’. Origin 2026SR1 software was used to draw the bar chart and perform Pearson correlation analysis; TBtools software was used to draw the heatmap analysis; OPLS-DA was performed using SIMCA-P 14.1 software.

3. Results and Discussion

3.1. Analysis of Major Quality Components in Different Tea Cultivars

The physicochemical factors that determine the quality grade of tea primarily include key components such as tea polyphenols, free amino acids, and water-soluble extracts [15]. Figure 1 illustrates the distribution characteristics of the major biochemical components in tea samples prepared from the six test cultivars. As a key component of total soluble solids, tea polyphenols are not only the primary substances responsible for the astringent and bitter flavors of tea but also play a significant role in enhancing the richness and body of the tea infusion [16]. In this study, the tea polyphenol content of the six tea cultivars showed significant inter-cultivar differences, with the content ranked from highest to lowest as follows: QM601 > CC4H > GZSC > SLX > SMCY > HJC1 (Figure 1A). The differences between any two groups were statistically significant, indicating that QM601 possesses a distinct cultivar advantage in polyphenol accumulation. Free amino acids are the key flavor components that determine the fresh and crisp taste of tea liquor [17]. Experimental data show that the amino acid content of HJC1 is significantly higher than that of the other test cultivars (Figure 1B), suggesting that it has superior potential for a fresh and crisp taste. Previous studies have shown that the concentration of aqueous extract directly affects the richness and fullness of the tea’s flavor, and is significantly correlated with the intensity of the aroma and the depth of the brewed tea’s color [18]. In this experiment, the water-soluble extract content of QM601, SMCY, and CC4H was higher than that of the other three cultivars (Figure 1C), indicating that these three cultivars have a better chemical basis for shaping the overall taste of the tea infusion. In addition, the ratio of polyphenols to amino acids (the phenol-to-amino acid ratio) is widely recognized as a key quantitative indicator for evaluating the freshness and balance between bitterness and astringency in green tea; it is generally believed that cultivars with a phenol-to-amino acid ratio below 8 are suitable for producing high-quality green tea [19,20]. As shown in Figure 1D, the phenol-to-amine ratios of all six test cultivars were below 8, meeting the basic threshold for green tea production. Among them, GZSC (5.50) has a relatively high phenol-to-amine ratio, this variety is typically processed into black tea in the Yunnan region.

3.2. Analysis of Volatile Aromatic Compounds in Different Tea Cultivars

To further investigate the differences in the composition of volatile compounds among different tea cultivars, this study employed headspace microextraction-gas chromatography-mass spectrometry (HS-SPME/GC-MS) to perform qualitative and quantitative analyses of volatile metabolites in six tea cultivars.

A total of 147 volatile compounds were identified and quantified, including 32 ketones, 24 aldehydes, 21 alcohols, 14 esters, 12 alkenes, 13 pyrazines, 7 acids, 5 furans, 2 pyrroles, and 17 other compounds (Figure 2A, Table 1).

Alcohols with floral and sweet notes were the most prevalent substances in teas, which occur not only in free forms but also in the form of glycosides [21]. Among the 147 volatile compounds, alcohols accounted for a relatively high proportion of the total, primarily including phenethyl alcohol, benzyl alcohol, geraniol, linalool, and α-pinene, which is consistent with the findings of previous studies on the composition of tea aroma compounds [22,23]. The total content of the six types of alcohol compounds showed a clear variety-dependent pattern, ranging from highest to lowest as follows: SMCY (1499.18 μg/kg) > QM601 (1209.36 μg/kg) > HJC (1203.54 μg/kg) > SLX (1130.01 μg/kg) > CC4H (1093.54 μg/kg) > GZSC (1090.69 μg/kg). It is worth noting that the extremely high alcohol content in SMCY is a key factor contributing to its excellent aromatic quality. As shown in Table 1, phenethyl alcohol, benzyl alcohol and linalool were present at high levels in SMCY, QM601, SLX and CC4H, whereas HJC and GZSC are characterized by phenethyl alcohol, geraniol, and linalool as their primary aromatic components. Alcohols are the primary contributors to the delicate floral and fruity aromas of green tea. Existing research has confirmed that linalool works synergistically to create floral, fruity, and woody notes [24,25]. Geraniol combines fruity, floral, and sweet aromas with a fresh, green leafy note, and is a key component of green tea’s floral notes, fresh, crisp aroma, and chestnut-like fragrance [26,27]. Phenethyl alcohol primarily contributes sweet and rose-like notes [28,29,30]. Differences in the composition of alcohol groups among different tea cultivars account for the distinct aromatic profiles observed in tea quality.

Among the 24 aldehydes detected, benzaldehyde, nonanal, tetradecanal, and β-cyclocitral were present in relatively high concentrations (Table 1). These components are commonly identified in green tea [31,32], and they jointly participate in the construction of tea aroma. A comparison of aldehyde content revealed that the total aldehyde content in both SLX and QM601 was higher than that in the other four cultivars, particularly the benzaldehyde content. The tetradecanal content in SLX was significantly higher than that in the other five cultivars. Relevant studies have verified that benzaldehyde features a distinct almond odor, while nonanal delivers rose-like notes at low concentrations [33]. Tetradecanal contributes floral and citrus aromas, and β-cyclocitral imparts a minty scent [34]. Collectively, these compounds serve as vital contributors to the formation of tea aroma.

Among the 32 ketone compounds identified, jasmone, β-ionone, 2,3-octanedione, and 6-methylhept-5-en-2-one were present in relatively high concentrations. Among them, the content of jasmone in SMCY was significantly higher than that in other cultivars. Previous studies have indicated that jasmone possesses floral and creamy-sweet aromas and may be related to the formation of the sweet, mellow floral aroma in green tea [35]. The content of 2,3-octanedione (with notes of grass and fennel) in SLX was significantly higher than in other cultivars, while the content of 6-methyl-5-hepten-2-one (with notes of apple and mushrooms) in CC4H was significantly higher than in other cultivars [36,37], indicating differentiated flux distribution in the lipoxygenase metabolic pathway among specific cultivars.

A total of 14 ester compounds were detected, among which methyl salicylate had the highest concentration, and its concentration in SLX was significantly higher than in other cultivars. Methyl salicylate has a characteristic minty aroma and is a common ester compound found in green tea [38]. In addition, the content of methyl palmitate in SMCY was significantly higher than in the other four cultivars. This compound primarily imparts waxy, oily, and iris-like aromas [39].

It is known that the Maillard reaction occurs very readily during the high-temperature processing of green tea, yellow tea, oolong tea, and black tea, and can produce various aromatic compounds such as pyrazines, furans, pyrroles, and their derivatives [40,41,42]. A total of 13 pyrazines, 5 furans, and 2 pyrroles were identified in this experiment, and the pyrazine and pyrrole contents in CC4H were significantly higher than those in other cultivars (Figure 2). Among these, 2,3-dimethylpyrazine and 2-methylpyrazine are important volatile compounds responsible for the “sweet” and “chestnut-like” characteristics [43].

In terms of olefin compounds, the total content of QM601, CC4H, and SLX was significantly higher than that of the other three cultivars. Among these, the QM601 variety contained significantly higher levels of limonene, isopinoene, γ-terpinene, (3E)-β-basilene, α-terpinene, β-pinene, and cubene than the other cultivars. Studies have confirmed that limonene, isopinoene, γ-terpinene, and cubene all exhibit lemon and citrus fruit aromas [44,45,46], while (3E)-β-ocimene possesses woody and sweet characteristics [47]. The synergistic accumulation of these compounds in QM601 may significantly enhance the release of its floral and fruity notes. In addition, the levels of caramene, α-bisabolene, and α-corene in SLX are significantly higher than in other cultivars, giving it a unique, aromatic undertone.

To visually illustrate the inter-varietal differences in volatile aroma compounds among the six tea cultivars under study (HJC1, CC4H, GZSC, QM601, SLX, and SMCY), this study established an orthogonal partial least squares discriminant analysis (OPLS-DA) model. As shown in Figure 2C, the first principal component (Comp 1) and the second principal component (Comp 2) in the OPLS-DA score plot explain 56.0% and 22.8% of the variance, respectively, with a cumulative variance explained of 78.8%, indicating that the first two principal components effectively capture the main variability in the original data. Based on the sample distribution, the six cultivars exhibit a distinct variety-specific clustering pattern on the scoring plot. Specifically, HJC1 and CC4H are concentrated on the positive end of Comp 1, while GZSC and QM601 show a high degree of spatial overlap on the negative end of Comp 1, suggesting a certain degree of similarity in their comprehensive metabolic profiles. SMCY and SLX exhibited relatively broad distributions at the positive and negative ends of Comp 2, respectively, reflecting their distinct flavor profiles. Overall, although there is some overlap among the different cultivars on the OPLS-DA score plot, each variety exhibits a relatively distinct cluster, indicating that the comprehensive spectral characteristics of their volatile aromas and biochemical components are variety-specific.

To further validate the effectiveness and reliability of the OPLS-DA model, this study conducted 200 permutation tests (Figure 2D). The results show that in the replacement test, both the original values of R² (the model’s explanatory power for the X variable) and Q² (the model’s predictive ability) were higher than the corresponding values for all replacement random models. Furthermore, the intercept of the Q² regression line was negative, indicating that the model does not exhibit overfitting and possesses good predictive ability and statistical reliability. The above results confirm that the OPLS-DA model based on volatile aroma compounds can effectively distinguish tea plant cultivars from different sources.

In summary, these six tea cultivars exhibit significant differences in their aromatic characteristics, which are primarily attributable to variations in the content of aromatic compounds among the different cultivars, as well as differences in the proportions of key aromatic compounds.

3.3. Confirmation of Odor-Active Compounds in Six Tea Cultivars

The final aroma profile of tea is determined by a combination of numerous volatile compounds, but not all identified volatile substances make a substantial contribution to the final aroma quality. Odor researchers note that odor compounds with an ROAV (Relative Odor Activity Value) greater than 1 are generally considered to contribute to the overall aroma profile of the sample being analyzed. In addition, odor compounds with a ROAV greater than 100 are considered to play a significant role in shaping the overall aroma of the sample being analyzed [48]. Based on this, this experiment calculated the ROAV (Relative Odor Activity Value) of each volatile compound to further identify the key flavor-forming compounds in six different tea cultivars.

As shown in Figure 3 and Table 2, a total of 36 key aroma-active compounds with ROAV values greater than 1 were identified, including aldehydes (11), ketones (7), esters (3), alcohols (4), alkenes (2), pyrazines (5), furans (1), and other classes (3), most of which present floral, fruity, and woody sensory notes. Among these, compounds with higher ROAV values include benzaldehyde (2804.17–6986.11), (E)-β-damascenone (616.33–5253.33), (3E)-β-ocimene (417.17–2018.33), β-ionone (836.51–1315.87), and 1-octene-3-one (531.11–998.89). These compounds were detected in all tea samples tested, and their ROAV values were all well above 100, indicating that these compounds form the core framework of the overall aromatic matrix in all samples. On the other hand, heterocyclic compounds with roasted or nutty aromas, such as 3-ethyl-2,5-dimethylpyrazine and 2,3-diethyl-5-methylpyrazine, were also identified as key contributors (all with ROAV values greater than 1), suggesting that heterocyclic compounds formed during thermal processes such as fixation and drying are crucial for the rich roasted and nutty aromas of green tea [49]. Furthermore, linalool, as a key aroma marker for many tea cultivars, had a ROAV greater than 1 in all six test cultivars in this study. Moreover, the ROAV for all cultivars except GZSC exceeded 10, further confirming the important role of linalool in shaping the floral aroma quality of tea [39].

3.4. Analysis of the Potential Regulatory Relationship Between Amino Acids and Tea Polyphenols on the Accumulation of Key Volatile Aromatic Compounds

To investigate whether the two major non-volatile flavor compounds in tea (amino acids and tea polyphenols) exhibit a statistically significant synergistic or antagonistic relationship with regard to the metabolic accumulation of volatile aroma compounds, this study conducted Pearson correlation analyses between each of these two compounds and key aroma compounds with ROAV values greater than 1 (Figure 4). It is important to emphasize that, given the complex substrate competition and enzymatic cascade reactions within the aroma metabolism network, statistical correlations merely suggest potential metabolic associations rather than direct causal relationships.

Amino acid content showed a significant negative correlation with β-cyclocitral, damascone, (E)-β-damascone, and methyl salicylate. It is hypothesized that the underlying mechanism involves high concentrations of amino acids competing with the carotenoid degradation pathway and the phenylpropanoid pathway for shared metabolic precursors or energy carriers, thereby inhibiting the enzymatic production efficiency of these floral-fruity and fresh-scented compounds [50]. In contrast, amino acids showed a significant positive correlation with 2-methylbutanal, heptanal, tetradecanal, isovaleraldehyde, β-violetone, and phenethyl alcohol. This is primarily because most of the aforementioned aldehydes and alcohols are either direct products of the Strecker degradation of amino acids (such as leucine, isoleucine, and phenylalanine) during thermal processing or secondary derivatives catalyzed and promoted by amino acid metabolic intermediates. The higher the abundance of the precursor substrates, the greater the accumulation of the corresponding products [51].

The tea polyphenol content showed a significant negative correlation with nonanal, hexanal, octanal, heptanal, safranal, 1-octen-3-one, jasmone, geraniol, 1-octen-3-ol, 2-pentylfuran, indole, and coumarin. Which may be attributed to the non-competitive inhibitory effect of tea polyphenols on lipoxygenase (LOX) and the activity of its downstream cleavage enzymes, combined with the physical adsorption and acid-mediated degradation effects of polyphenolic compounds on aldehydes and ketones, thereby reducing the content of the aforementioned aroma compounds, which are primarily derived from lipid oxidation [52]. Tea polyphenols showed a significant positive correlation with 2-methylbutanal, isovaleraldehyde, linalyl acetate, linalool, (3E)-β-ocimene, α-phellandrene, and p-cymene. On the one hand, quinone intermediates formed by the oxidation of polyphenols may mediate the oxidative decarboxylation of branched-chain aldehydes [53]. On the other hand, the strong reducing properties and antioxidant protection provided by tea polyphenols can effectively maintain the stability of the unsaturated double bonds in terpenes and terpenoids, preventing their premature oxidative degradation during processing, thereby exhibiting a phenotypic association with the co-accumulation of terpenoid aroma compounds.

4. Conclusions

In summary, the six tea cultivars originating from different regions exhibited significant quality when cultivated under the same ecological conditions in Meitan, Guizhou. Among the introduced cultivars, SMCY showed the richest floral and aromatic profiles, SLX stood out for its high concentration of floral and fruity aldehydes and esters, CC4H displayed a notable roasted sweetness, and HJC1 offered the best amino acid-derived freshness. The local variety QM601 exhibits a distinct advantage in the synergistic accumulation of tea polyphenols and fruity terpenes, whereas GZSC with its relatively high phenol-to-amine ratio, may be more suitable for black tea processing. On this basis, we recommended that tea-growing regions in Guizhou adopt a flavor-oriented, differentiated deployment of introduced cultivars to develop diverse, and distinctive tea products, while also conducting genetic improvement focused on flavor harmony and ecological adaptability using local cultivars as core parental lines.

Supplementary Materials

The following supporting information can be downloaded at the website of this paper posted on Preprints.org, Table S1: Sources of aroma descriptions and thresholds for key volatile compounds.

Author Contributions

M.G. (Manman Gao): Investigation, methodology, formal analysis, data curation, writing-original draft and funding acquisition; K.Z. (Kai Zhang): experimental sample processing, investigation, methodology, data curation; M.G. and K.Z.: Sample, tea processing, resources; H.W. (Huan Wang): methodology and validation, data curation; H.S.: funding acquisition and project administration, writing—review and editing. All authors have read and agreed to the published version of the manuscript.

Funding

This research was funded by Zunyi Municipal Bureau of Industry, Science and Technology (Zunyi Kehe HZ Zi (2024) No. 335), Zunyi Municipal Bureau of Industry, Science and Technology (Zunyi Kehe HZ Zi (2022) No. 410), Guizhou Provincial Department of Science and Technology (Qian Ke He Platform Talents [2021] 1350-070), Zunyi Medical University (Doctoral Research Fund, No. ZMUDRF2025-19), and Guizhou Provincial Department of Science and Technology (Qian Ke He Ji Chu [2026] 002-55).

Conflicts of Interest

The authors declare no conflicts of interest.

Acknowledgments

While writing this manuscript, the author used DeepL for English translation. The author has reviewed and revised the generated results and assumes full responsibility for the content of this publication.

Abbreviations

CC4H	Chuancha 4
SLX	Shilixiang
SMCY	Siming Cuiya
HJC1	Huangjincha 1
QM601	Qianmei 601
GZSC	Guizhou Zise Tea
HS-SPME	headspace solid-phase microextraction
GC/MS	gas chromatography-mass spectrometry
DVB/CWR/PDMS	divinylbenzene/carbon wide range/polydimethylsiloxane
ROAV	the relative odor activity value
OPLS-DA	Orthogonal partial least squares discriminant analysis

Appendix A

Appendix A.1

Table A1. Sources of aroma descriptions and thresholds for key volatile compounds.

Metabolite	Odour	CAS ID	Threshold (μg/L or μg/kg)	References
Nonanal	waxy; fatty; citrus; rose; fat; orange peel; grapefruit; green; fish; fresh; orris; aldehydic; lime	124-19-6	1.1	Chen, H. Y., Ying, J. Q., An, H. M., Chen, Y., Huang, Y. W., Jiang, Y. C., Wang, S. R., Bai, S. L., Li, S., Huang, J. A., & Liu, Z. H. (2025). Chinese Jasmine Tea: The Harmonious Intertwining of Tea and Jasmine Fragrance. Comprehensive reviews in food science and food safety, 24(4), e70210. https://doi.org/10.1111/1541-4337.70210.
Hexanal	fatty; leafy; fat; sweaty; green; tallow; fresh; grass; aldehydic; fruity	66-25-1	4.5	Xu, J., Zhang, Y., Yan, F., Tang, Y., Yu, B., Chen, B., Lu, L., Yuan, L., Wu, Z., & Chen, H. (2022). Monitoring Changes in the Volatile Compounds of Tea Made from Summer Tea Leaves by GC-IMS and HS-SPME-GC-MS. Foods (Basel, Switzerland), 12(1), 146. https://doi.org/10.3390/foods12010146.
β-Cyclocitral	rose oxide; tobacco; sweet; saffron; tropical; minty; clean; herbal; damascone; mint; fruity	432-25-7	3	Chen, H., Jiang, R., An, H., Xu, H., Ou, X., Wang, K., Chen, Y., Jiang, Y., Li, S., Huang, J., & Liu, Z. (2026). Characterization of key odor-active volatiles in jasmine green tea by sensomics and chemometrics. Food chemistry: X, 34, 103695. https://doi.org/10.1016/j.fochx.2026.103695.
Benzaldehyde	cherry; vanilla; almond; fruity; sweet; caramel; sharp; strong; bitter; bitter almond	100-52-7	0.024	Guo, X., Schwab, W., Ho, C. T., Song, C., & Wan, X. (2022). Characterization of the aroma profiles475 of oolong tea made from three tea cultivars by both GC-MS and GC-IMS. Food Chemistry, 376:476 131933. http://doi.org/10.1016/j.foodchem.2021.131933.
2-Methylbutyraldehyde	coffee; malty; almond; musty; cocoa; nutty	96-17-3	1.5	Cui, L., Wang, X., He, C., Liu, Z., & Liang, J. (2024). Effect of puffing treatment on volatile components of green tea explored by gas chromatography-mass spectrometry and gas chromatography-olfactometry. Food chemistry: X, 23, 101746. https://doi.org/10.1016/j.fochx.2024.101746.
Octanal	waxy; lemon; fatty; citrus; fat; orange peel; green; aldehydic; soapy	124-13-0	0.8	Chen, H., Jiang, R., An, H., Xu, H., Ou, X., Wang, K., Chen, Y., Jiang, Y., Li, S., Huang, J., & Liu, Z. (2026). Characterization of key odor-active volatiles in jasmine green tea by sensomics and chemometrics. Food chemistry: X, 34, 103695. https://doi.org/10.1016/j.fochx.2026.103695.
Heptanal	fatty; citrus; wine-lee; fat; rancid; ozone; green; herbal; fresh; aldehydic	111-71-7	2.8	Chen, H., Jiang, R., An, H., Xu, H., Ou, X., Wang, K., Chen, Y., Jiang, Y., Li, S., Huang, J., & Liu, Z. (2026). Characterization of key odor-active volatiles in jasmine green tea by sensomics and chemometrics. Food chemistry: X, 34, 103695. https://doi.org/10.1016/j.fochx.2026.103695.
Tetradecanal	dry; musky; flower; fatty; waxy; incense; wax; citrus peel	124-25-4	67	Li, H., Chen, J., Zhang, Y., Jiang, Y., Sun, D., Piao, C., Li, T., Wang, J., Li, H., Mu, B., & Li, G. (2024). Evaluation of the flavor profiles of Yanbian-style sauced beef from differently treated raw beef samples. Food chemistry: X, 22, 101505. https://doi.org/10.1016/j.fochx.2024.101505.
Safranal	phenolic; spicy; tobacco; sweet; metallic; herbal; fresh; rosemary	116-26-7	3	Xu, J., Zhang, Y., Yan, F., Tang, Y., Yu, B., Chen, B., Lu, L., Yuan, L., Wu, Z., & Chen, H. (2022). Monitoring Changes in the Volatile Compounds of Tea Made from Summer Tea Leaves by GC-IMS and HS-SPME-GC-MS. Foods (Basel, Switzerland), 12(1), 146. https://doi.org/10.3390/foods12010146.
Isovaleraldehyde	fatty; peach; malty; chocolate; sour; aldehydic	590-86-3	0.5	Cui, L., Wang, X., He, C., Liu, Z., & Liang, J. (2024). Effect of puffing treatment on volatile components of green tea explored by gas chromatography-mass spectrometry and gas chromatography-olfactometry. Food chemistry: X, 23, 101746. https://doi.org/10.1016/j.fochx.2024.101746.
Decanal	waxy; citrus; sweet; orange peel; tallow; aldehydic; soapy	112-31-2	3	Chen, H., Jiang, R., An, H., Xu, H., Ou, X., Wang, K., Chen, Y., Jiang, Y., Li, S., Huang, J., & Liu, Z. (2026). Characterization of key odor-active volatiles in jasmine green tea by sensomics and chemometrics. Food chemistry: X, 34, 103695. https://doi.org/10.1016/j.fochx.2026.103695.
1-Octen-3-One	mushroom; earthy; metallic; musty; dirty; herbal	4312-99-6	0.003	Sacks, D., Baxter, B., Campbell, B. C. V., Carpenter, J. S., Cognard, C., Dippel, D., Eesa, M., Fischer, U., Hausegger, K., Hirsch, J. A., Shazam Hussain, M., Jansen, O., Jayaraman, M. V., Khalessi, A. A., Kluck, B. W., Lavine, S., Meyers, P. M., Ramee, S., Rüfenacht, D. A., … Vorwerk, D. (2018). Multisociety Consensus Quality Improvement Revised Consensus Statement for Endovascular Therapy of Acute Ischemic Stroke. International journal of stroke: official journal of the International Stroke Society, 13(6), 612–632. https://doi.org/10.1177/1747493018778713.
Jasmone	spicy; jasmine; celery; herbal; woody; jasmin	488-10-8	1.9	Chen, H., Jiang, R., An, H., Xu, H., Ou, X., Wang, K., Chen, Y., Jiang, Y., Li, S., Huang, J., & Liu, Z. (2026). Characterization of key odor-active volatiles in jasmine green tea by sensomics and chemometrics. Food chemistry: X, 34, 103695. https://doi.org/10.1016/j.fochx.2026.103695.
β-Ionone	dry; flower; powdery; jam; seaweed; violet; orange; woody; orris; raspberry	79-77-6	0.021	Cui, L., Wang, X., He, C., Liu, Z., & Liang, J. (2024). Effect of puffing treatment on volatile components of green tea explored by gas chromatography-mass spectrometry and gas chromatography-olfactometry. Food chemistry: X, 23, 101746. https://doi.org/10.1016/j.fochx.2024.101746.
2,3-Octanedione	cooked; buttery; broccoli; dill	585-25-1	12	Li, H., Chen, J., Zhang, Y., Jiang, Y., Sun, D., Piao, C., Li, T., Wang, J., Li, H., Mu, B., & Li, G. (2024). Evaluation of the flavor profiles of Yanbian-style sauced beef from differently treated raw beef samples. Food chemistry: X, 22, 101505. https://doi.org/10.1016/j.fochx.2024.101505.
Damascenone	apple; tobacco; rose; smoke; honey; sweet; apple. rose	23726-93-4	0.006	Cui, L., Wang, X., He, C., Liu, Z., & Liang, J. (2024). Effect of puffing treatment on volatile components of green tea explored by gas chromatography-mass spectrometry and gas chromatography-olfactometry. Food chemistry: X, 23, 101746. https://doi.org/10.1016/j.fochx.2024.101746.
(E)- β-Damascone	apple; tobacco; rose; plum; honey; blackcurrant; berry; fruity	23726-91-2	0.001	Xue, Y., Chen, G., Zhang, J., Zhu, G., Zheng, X., Xie, H., Wang, Z., Li, D., Huang, J., Liu, Z., & Wang, C. (2026). Cultivar-specific aroma divergence in multi-type teas: Comparative study of five cultivars processed into green, white, and black teas. Food chemistry: X, 34, 103498. https://doi.org/10.1016/j.fochx.2026.103498.
(E, E)-3,5-Octadien-2-One	grassy; mushroom; fatty; fruity; green	38284-27-4	0.1	Wang, D., Wang, C., Su, W., Lin, C. C., Liu, W., Liu, Y., Ni, L., & Liu, Z. (2023). Characterization of the Key Aroma Compounds in Dong Ding Oolong Tea by Application of the Sensomics Approach. Foods (Basel, Switzerland), 12(17), 3158. https://doi.org/10.3390/foods12173158.
Methyl Salicylate	wintergreen; minty; peppermint	119-36-8	40	Chen, H., Jiang, R., An, H., Xu, H., Ou, X., Wang, K., Chen, Y., Jiang, Y., Li, S., Huang, J., & Liu, Z. (2026). Characterization of key odor-active volatiles in jasmine green tea by sensomics and chemometrics. Food chemistry: X, 34, 103695. https://doi.org/10.1016/j.fochx.2026.103695.
Linalyl Acetate	citrus; sweet; lavender; fruity; green; bergamot; woody	115-95-7	0.1109	Elsharif, S. A., Banerjee, A., & Buettner, A. (2015). Structure-odor relationships of linalool, linalyl acetate and their corresponding oxygenated derivatives. Frontiers in chemistry, 3, 57. https://doi.org/10.3389/fchem.2015.00057.
Methyl Nonanoate	waxy; coconut; sweet; pear; tropical; fruity; wine	1731-84-6	0.04	Chen, H., Jiang, R., An, H., Xu, H., Ou, X., Wang, K., Chen, Y., Jiang, Y., Li, S., Huang, J., & Liu, Z. (2026). Characterization of key odor-active volatiles in jasmine green tea by sensomics and chemometrics. Food chemistry: X, 34, 103695. https://doi.org/10.1016/j.fochx.2026.103695.
Phenylethyl Alcohol	lilac; rose flower; rose water; honey; rose; rose dried; bitter; spice	20-12-8	564.23	Chen, H., Jiang, R., An, H., Xu, H., Ou, X., Wang, K., Chen, Y., Jiang, Y., Li, S., Huang, J., & Liu, Z. (2026). Characterization of key odor-active volatiles in jasmine green tea by sensomics and chemometrics. Food chemistry: X, 34, 103695. https://doi.org/10.1016/j.fochx.2026.103695.
Geraniol	waxy; citrus; rose; geranium; sweet; fruity	106-24-1	6.6	Chen, H., Jiang, R., An, H., Xu, H., Ou, X., Wang, K., Chen, Y., Jiang, Y., Li, S., Huang, J., & Liu, Z. (2026). Characterization of key odor-active volatiles in jasmine green tea by sensomics and chemometrics. Food chemistry: X, 34, 103695. https://doi.org/10.1016/j.fochx.2026.103695.
Linalool	flower; lemon; citrus; sweet; lavender; green; orange; woody; blueberry	78-70-6	6	Chen, H., Jiang, R., An, H., Xu, H., Ou, X., Wang, K., Chen, Y., Jiang, Y., Li, S., Huang, J., & Liu, Z. (2026). Characterization of key odor-active volatiles in jasmine green tea by sensomics and chemometrics. Food chemistry: X, 34, 103695. https://doi.org/10.1016/j.fochx.2026.103695.
1-Octen-3-Ol	fungal; mushroom; earthy; raw; green; fish; chicken; oily	3391-86-4	1.5	Chen, H., Jiang, R., An, H., Xu, H., Ou, X., Wang, K., Chen, Y., Jiang, Y., Li, S., Huang, J., & Liu, Z. (2026). Characterization of key odor-active volatiles in jasmine green tea by sensomics and chemometrics. Food chemistry: X, 34, 103695. https://doi.org/10.1016/j.fochx.2026.103695.
(3E)-β-Ocimene	woody; citrus; herbal; tropical; green; sweet; terpene	13877-91-3	0.02	Ye, F., Gui, A., Qiao, X., Liu, P., Wang, X., Wang, S., Feng, L., Teng, J., Xue, J., Chen, X., Mei, Y., Zhang, B., Han, H., Liao, A., Zheng, P., & Gao, S. (2025). Effects of Roasting Process on Sensory Qualities, Color, Physicochemical Components, and Identification of Key Aroma Compounds in Hubei Strip-Shaped Green Tea. Metabolites, 15(3), 155. https://doi.org/10.3390/metabo15030155.
α-Phellandrene	citrus; peppery; green; turpentine; woody; herbal; terpene; minty; spice	99-83-2	0.04	Zhao, Z., Hao, Y., Liu, Y., Shi, Y., Lin, X., Wang, L., Wen, P., Hu, X., & Li, J. (2023). Comprehensive evaluation of aroma and taste properties of different parts from the wampee fruit. Food chemistry: X, 19, 100835. https://doi.org/10.1016/j.fochx.2023.100835.
3-Ethyl-2,5-Dimethylpyrazine	cocoa; nutty; potato; roast; roasted	13360-65-1	25	Cui, L., Wang, X., He, C., Liu, Z., & Liang, J. (2024). Effect of puffing treatment on volatile components of green tea explored by gas chromatography-mass spectrometry and gas chromatography-olfactometry. Food chemistry: X, 23, 101746. https://doi.org/10.1016/j.fochx.2024.101746.
2-Ethyl-5-Methylpyrazine	sweet; bean; fruity; coffee	13360-64-0	16	Cui, L., Wang, X., He, C., Liu, Z., & Liang, J. (2024). Effect of puffing treatment on volatile components of green tea explored by gas chromatography-mass spectrometry and gas chromatography-olfactometry. Food chemistry: X, 23, 101746. https://doi.org/10.1016/j.fochx.2024.101746.
2,5-Diethylpyrazine	-	13238-84-1	0.02	Cui, L., Wang, X., He, C., Liu, Z., & Liang, J. (2024). Effect of puffing treatment on volatile components of green tea explored by gas chromatography-mass spectrometry and gas chromatography-olfactometry. Food chemistry: X, 23, 101746. https://doi.org/10.1016/j.fochx.2024.101746.
2,3-Diethyl-5-Methylpyrazine	vegetable; wine; earthy; meat; potato; citrus; fatty; roast; musty; herbal; nutty; spicy; green; hazelnut; woody; fruity; meaty	18138-04-0	0.031	Cui, L., Wang, X., He, C., Liu, Z., & Liang, J. (2024). Effect of puffing treatment on volatile components of green tea explored by gas chromatography-mass spectrometry and gas chromatography-olfactometry. Food chemistry: X, 23, 101746. https://doi.org/10.1016/j.fochx.2024.101746.
3,5-Diethyl-2-Methylpyrazine	vegetable; nutty; roast; meaty	18138-05-1	0.26	Cui, L., Wang, X., He, C., Liu, Z., & Liang, J. (2024). Effect of puffing treatment on volatile components of green tea explored by gas chromatography-mass spectrometry and gas chromatography-olfactometry. Food chemistry: X, 23, 101746. https://doi.org/10.1016/j.fochx.2024.101746.
2-Pentylfuran	buttery; earthy; metallic; green bean; green; vegetable; fruity; beany	3777-69-3	5.8	Cui, L., Wang, X., He, C., Liu, Z., & Liang, J. (2024). Effect of puffing treatment on volatile components of green tea explored by gas chromatography-mass spectrometry and gas chromatography-olfactometry. Food chemistry: X, 23, 101746. https://doi.org/10.1016/j.fochx.2024.101746.
P-Cymene	solvent; citrus; gasoline; terpene; woody; fresh; spice	99-87-6	11.4	Xu, J., Zhang, Y., Yan, F., Tang, Y., Yu, B., Chen, B., Lu, L., Yuan, L., Wu, Z., & Chen, H. (2022). Monitoring Changes in the Volatile Compounds of Tea Made from Summer Tea Leaves by GC-IMS and HS-SPME-GC-MS. Foods (Basel, Switzerland), 12(1), 146. https://doi.org/10.3390/foods12010146.
Indole	fecal; moth ball; fish; jasmine; honey; animal; naphthelene; mothball; burnt	120-72-9	11	Chen, H., Jiang, R., An, H., Xu, H., Ou, X., Wang, K., Chen, Y., Jiang, Y., Li, S., Huang, J., & Liu, Z. (2026). Characterization of key odor-active volatiles in jasmine green tea by sensomics and chemometrics. Food chemistry: X, 34, 103695. https://doi.org/10.1016/j.fochx.2026.103695.
Coumarin	bitter; sweet; green; new mown hay	91-64-5	11	Cui, L., Wang, X., He, C., Liu, Z., & Liang, J. (2024). Effect of puffing treatment on volatile components of green tea explored by gas chromatography-mass spectrometry and gas chromatography-olfactometry. Food chemistry: X, 23, 101746. https://doi.org/10.1016/j.fochx.2024.101746.

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Figure 1. Content of major quality components in different tea cultivars (A: Tea polyphenols; B: Amino acids; C: Aqueous extract; D: Ratio of polyphenols to amino).

Figure 2. Analysis of volatile compounds in different tea cultivars (A: Pie chart of volatile compound types; B: Stacked histogram of volatile compounds; C: OPLS-DA plot of volatile compounds; D: Permutation test).

Figure 3. Heat map of potential key aroma compounds in processed teas from 6 different tea cultivars.

Figure 4. (A) Pearson correlation analysis between amino acids and key aroma compounds. (B) Pearson correlation analysis between tea polyphenols and key aroma compounds.

Table 1. The relative content of aroma components in six different tea cultivars (μg/kg).

Compounds	Retention time	RI	CAS	HJC1	CC4H	GZSC	QM601	SLX	SMCY
Aldehydes
Nonanal	7.532	1391	124-19-6	28.23±4.86ab	32.53±2.84a	20.33±0.80cd	13.27±0.15e	19.93±2.30d	27.67±0.91b
4-Methylbenzaldehyde	10.82	1623	104-87-0	2.50±0.29b	2.20±0.17b	3.76±0.22a	2.10±0.14b	2.42±0.33b	3.21±0.13ab
Hexanal	3.194	1083	66-25-1	5.44±0.79bc	5.98±0.38ab	5.10±0.29c	3.58±0.22d	4.93±0.29c	6.21±0.38a
Valeraldehyde	2.319	979	110-62-3	3.58±0.32ab	4.08±0.15a	2.76±0.21cd	2.54±0.09d	3.83±0.64ac	3.51±0.26bc
β-Cyclocitral	10.783	1611	432-25-7	7.48±0.91d	11.20±1.31b	11.77±0.81ab	10.25±0.64c	12.06±1.99a	9.77±0.35c
Furfural	8.607	1461	98-01-1	1.47±0.15c	8.49±0.69a	3.15±0.35b	2.47±0.09b	4.11±1.73b	1.69±0.23c
Salicylaldehyde	11.418	1670	90-02-8	1.83±0.25b	2.29±0.12a	2.05±0.14ab	1.75±0.12c	2.60±0.29a	1.93±0.14bc
Benzaldehyde	9.458	1520	100-52-7	83.40±10.11b	85.87±4.50b	67.30±3.55c	167.67±11.50a	85.57±11.95b	108.30±7.43b
2,6-Dimethyl-5-Heptenal	6.313	1357	106-72-9	4.41±0.40c	6.30±0.60a	5.61±0.42ab	5.30±0.35b	6.52±1.06a	4.53±0.26c
2-Methylbutyraldehyde	1.933	914	96-17-3	17.13±1.67b	10.13±0.41d	10.92±1.02d	46.87±3.02a	18.23±3.06b	6.31±0.50e
5-Methylfurfural	10.216	1570	620-02-0	4.55±0.57d	28.20±1.97a	11.77±0.81b	8.13±0.42c	12.00±2.13b	4.32±0.29d
Octanal	5.933	1289	124-13-0	4.71±0.78bc	5.48±0.48b	3.02±0.22d	2.08±0.03e	3.38±0.50cd	5.03±0.27bc
Methylglyoxal	2.313	970	78-98-8	0.30±0.03ab	0.31±0.03a	0.23±0.02c	0.18±0.01d	0.30±0.04ab	0.25±0.03bc
Heptanal	4.439	1185	111-71-7	11.75±2.00a	9.75±0.90ab	9.12±0.51b	4.24±0.05c	8.13±1.02b	8.72±0.63b
Pyrrole-2-Carboxaldehyde	13.935	2030	1003-29-8	6.24±0.77c	11.73±0.90a	5.42±0.21c	4.36±0.29d	5.40±0.85c	3.07±0.06e
2-Heptenal	6.447	1323	18829-55-5	0.43±0.07d	0.93±0.19a	0.57±0.08c	0.53±0.11c	1.03±0.17a	0.92±0.03ab
Tetradecanal	13.325	1930	124-25-4	77.97±9.08b	23.30±2.16d	27.73±1.19d	10.26±0.26e	109.67±7.77a	29.57±0.21c
Safranal	11.062	1648	116-26-7	9.85±1.13b	11.80±1.20a	11.70±0.70a	9.28±0.71b	11.02±1.53a	10.93±0.55a
Isovaleraldehyde	1.951	918	590-86-3	5.56±0.63a	1.11±0.04d	1.25±0.10d	5.11±0.31a	3.41±0.58c	2.59±0.20c
2-Hexenal	4.894	1216	6728-26-3	0.55±0.05c	0.23±0.02d	0.76±0.05a	0.37±0.02d	0.45±0.05c	1.34±0.07a
Cis-Cinnamaldehyde	12.942	1884	57194-69-1	0.13±0.01b	0.17±0.01a	0.16±0.02a	0.13±0.01b	0.18±0.04a	0.14±0.02b
Decanal	9.137	1498	112-31-2	2.43±0.62b	2.61±0.03ab	2.10±0.13bc	1.67±0.05c	3.02±0.99a	2.09±0.51bc
Citral	11.906	1732	141-27-5	0.74±0.10b	0.38±0.04d	1.31±0.06a	0.47±0.04cd	0.42±0.04d	0.69±0.02bc
α-Cyclocitral	8.169	1425	432-24-6	0.42±0.05c	0.63±0.05a	0.60±0.04a	0.47±0.02bc	0.63±0.05a	0.48±0.04b
Ketones
2,3-Pentanedione	2.968	1054	600-14-6	1.27±0.12c	2.51±0.23a	1.76±0.19b	1.07±0.03c	2.02±0.39ab	1.01±0.02c
1-Octen-3-One	6.116	1301	4312-99-6	1.75±0.25c	2.52±0.26b	1.96±0.17c	1.59±0.18c	2.84±0.33a	3.00±0.17a
3-Penten-2-One	3.697	1122	3102-33-8	3.79±0.64a	2.23±0.80bc	1.99±0.27c	2.93±0.52ab	2.33±0.02bc	2.21±0.18bc
Methyl Ethyl Ketone	1.87	945	78-93-3	0.57±0.08ab	0.41±0.03c	0.37±0.04c	0.69±0.06a	0.56±0.18ab	0.50±0.05bc
Jasmone	13.435	1961	488-10-8	3.46±0.51d	20.20±1.74a	6.79±0.21c	11.67±0.97b	15.03±1.85a	30.83±0.40a
Mesityl Oxide	3.767	1127	141-79-7	6.56±0.34d	13.57±0.75b	15.03±0.40a	14.60±1.23ab	23.03±2.19a	6.87±0.47d
3-Octen-2-One	7.715	1396	1669-44-9	1.17±0.17c	2.51±0.17a	2.11±0.22b	1.30±0.05c	1.99±0.17b	1.93±0.14b
Benzophenone	16.254	2508	119-61-9	1.76±0.27b	2.22±0.33a	2.05±0.05ab	1.60±0.06b	2.05±0.16ab	1.29±0.03c
3-Octanone	5.409	1253	106-68-3	1.08±0.14ab	1.12±0.05a	1.00±0.10b	0.71±0.05c	1.05±0.18ab	1.21±0.05a
2-Octanone	5.862	1285	111-13-7	2.62±0.38c	3.24±0.14a	2.46±0.19c	1.55±0.08d	2.89±0.47bc	2.84±0.22bc
2’-Aminoacetophenone	14.968	2223	551-93-9	0.74±0.12a	0.56±0.03bc	0.48±0.00c	0.25±0.01d	0.52±0.06c	0.44±0.02c
Isophorone	10.399	1591	78-59-1	1.51±0.21b	1.69±0.11a	1.39±0.09c	0.88±0.06d	1.60±0.19ab	1.13±0.04c
β-Ionone	13.411	1941	79-77-6	27.63±3.67a	20.23±2.45b	19.57±1.02b	17.57±0.21b	23.30±2.69ab	20.23±0.21b
2-Methyl-1-Penten-3-One	3.034	1069	25044-01-3	6.66±0.83c	8.39±0.58a	5.49±0.51d	7.92±0.36ab	6.73±1.26c	5.09±0.24d
2-Heptanone	4.393	1182	110-43-0	8.88±1.23ab	9.22±0.47a	7.83±0.60c	5.01±0.31d	8.07±1.27bc	8.75±0.80ab
2,3-Octanedione	6.489	1335	585-25-1	27.50±2.72bc	31.27±2.05ab	22.73±4.21c	27.00±1.30bc	39.00±7.66a	27.50±1.65bc
2(5H)-Furanone	12.1	1743	497-23-4	0.17±0.02c	0.35±0.03a	0.17±0.03c	0.08±0.01d	0.31±0.14ab	0.26±0.03b
6-Methyl-5-Hepten-2-One	6.662	1336	110-93-0	35.00±3.38c	49.90±4.83a	46.53±3.07ab	38.30±1.99c	44.60±7.25b	44.93±2.27b
Nerylacetone	12.855	1838	3879-26-3	9.85±1.31c	15.47±2.04a	17.07±1.11a	10.59±0.72c	14.40±1.90ab	12.27±0.32b
1-Hepten-3-One	5.159	1221	2918-13-0	0.29±0.10b	0.32±0.09b	0.32±0.04b	0.38±0.27b	0.51±0.35a	0.20±0.01c
2,4-Dimethyl-3-Hexanone	4.18	1178	18641-70-8	2.44±0.30c	3.84±0.61a	3.52±0.21ab	2.21±0.11c	4.54±1.54a	2.16±0.10c
Damascenone	12.609	1813	23726-93-4	0.32±0.05d	0.56±0.03b	0.62±0.02a	0.31±0.02d	0.67±0.08a	0.19±0.01e
(E)-β-Damascone	12.909	1830	23726-91-2	0.62±0.11c	1.00±0.13b	2.25±3.40ab	4.17±0.26a	1.27±0.13bc	5.25±0.12a
Furaneol	13.947	2031	3658-77-3	2.70±0.36c	8.67±1.17a	5.54±0.30b	2.01±0.53c	4.73±0.67b	1.89±0.05c
(E, E)-3,5-Octadien-2-One	9.424	1522	38284-27-4	3.38±0.36d	8.61±0.62a	6.04±0.21c	7.97±0.43b	6.14±0.80c	11.03±0.70a
1-(3,5-Dimethylpyrazinyl)-Ethanone	11.347	1629	54300-08-2	0.28±0.03b	0.55±0.04a	0.34±0.03b	0.14±0.01d	0.30±0.03bc	0.10±0.01e
2-Pentanone	2.308	983	107-87-9	0.07±0.01b	0.10±0.00a	0.08±0.01b	0.07±0.00b	0.10±0.02a	0.09±0.01ab
2,6-Dimethyl-4-Hepten-3-One	12.19	1754	56259-14-4	0.26±0.03c	0.30±0.02b	0.25±0.02c	0.21±0.01d	0.40±0.05a	0.34±0.00b
2,5-Dimethyl-3-Hexanone	4.234	1145	1888-57-9	0.05±0.02b	0.13±0.04a	0.09±0.04ab	0.05±0.00b	0.11±0.11ab	0.04±0.01b
2-Nonanone	7.443	1388	821-55-6	0.52±0.09c	0.68±0.05b	0.54±0.06c	0.30±0.01d	0.54±0.10c	2.22±0.19a
2-Pentadecanone	13.883	2019	2345-28-0	0.27±0.05c	0.42±0.03a	0.34±0.03b	0.24±0.03c	0.34±0.04b	0.26±0.00c
Ethyl Vinyl Ketone	2.629	1019	1629-58-9	0.21±0.03b	0.11±0.01c	0.15±0.02c	0.19±0.02bc	0.24±0.04b	0.43±0.03a
Esters
Methyl Palmitate	14.911	2209	112-39-0	4.21±0.48d	5.13±0.27c	6.57±0.31a	5.75±0.06b	5.29±0.74c	10.10±0.30a
Methyl Hexanoate	4.469	1184	106-70-7	6.33±0.69a	3.19±0.20c	5.23±0.41b	2.21±0.09d	3.78±0.52c	6.15±0.58a
(Z)-Acetate 3-Hexen-1-Ol	6.905	1327	3681-71-8	2.83±0.29a	0.23±0.01e	1.56±0.07c	2.42±0.14b	0.71±0.10d	0.18±0.01e
Phenethyl Acetate	12.364	1813	103-45-7	2.05±0.31b	0.82±0.07d	0.77±0.03d	1.05±0.08c	0.73±0.12d	3.47±0.23a
Pentyl Hexanoate	9.331	1510	540-07-8	0.19±0.04c	0.23±0.02b	0.16±0.01d	0.09±0.00e	0.22±0.02b	0.14±0.01d
Methyl Octanoate	7.48	1389	111-11-5	1.10±0.20c	1.22±0.13bc	1.04±0.06c	1.27±0.08b	1.14±0.16c	3.00±0.26a
Methyl Salicylate	12.271	1766	119-36-8	29.87±4.14d	61.93±6.83c	93.47±5.03a	69.93±4.82c	112.17±14.46a	65.43±2.06c
Methyl Anthranilate	15.062	2260	134-20-3	3.03±0.51c	4.47±0.38a	1.92±0.04d	2.63±0.28c	1.83±0.22d	2.02±0.09d
Methyl Linoleate	16.233	2482	112-63-0	1.97±0.21b	1.94±0.10b	3.17±0.10a	1.93±0.15b	2.29±0.27b	5.57±0.16a
Linalyl Acetate	9.445	1555	115-95-7	0.45±0.04d	6.92±0.59a	1.41±0.10c	3.72±0.30b	2.58±0.29b	2.40±0.11b
(Z)-Benzoate 3-Hexen-1-Ol	14.475	2126	25152-85-6	0.05±0.01a	0.05±0.00a	0.04±0.00ab	0.03±0.00b	0.06±0.01a	0.05±0.01a
γ-Caprolactone	11.627	1694	695-06-7	1.44±0.16c	1.91±0.08a	1.48±0.07c	1.18±0.07d	1.82±0.21ab	1.89±0.11ab
γ-Decalactone	14.589	2163	706-14-9	0.33±0.05c	0.56±0.04a	0.41±0.02b	0.23±0.01d	0.42±0.05b	0.32±0.02c
Methyl Nonanoate	9.046	1493	1731-84-6	0.08±0.01d	0.17±0.01b	0.14±0.01c	0.18±0.00a	0.14±0.02c	0.39±0.02a
Alcohols
Phenylethyl Alcohol	13.236	1907	60-12-8	681.67±51.48a	424.67±15.28c	491.00±8.72b	444.33±15.53c	378.67±31.72d	766.33±10.21a
Geraniol	12.787	1847	106-24-1	105.20±14.38a	60.97±5.25c	179.33±8.08a	66.57±4.68c	67.23±8.47c	88.10±2.51b
Linalool	9.851	1547	78-70-6	72.63±8.33c	113.00±6.24b	42.23±1.99d	261.33±11.24a	144.00±19.52b	147.33±7.23b
1-Octanol	9.996	1557	111-87-5	32.03±4.73b	37.47±1.45a	25.83±1.27c	20.03±0.93d	31.43±4.34b	29.50±1.32b
1-Undecanol	11.707	1719	112-42-5	2.94±0.47c	4.48±0.41a	4.32±0.15a	3.20±0.25c	4.73±0.48a	2.80±0.13c
1-Octen-3-Ol	8.375	1450	3391-86-4	19.70±2.44c	29.10±3.46a	23.33±1.55b	19.30±0.98c	27.93±4.35a	26.30±1.51ab
Benzyl Alcohol	13.005	1870	100-51-6	195.00±20.95d	276.00±9.54c	249.67±6.81c	204.33±8.96d	304.00±29.05b	348.33±10.69a
1-Penten-3-Ol	4.073	1157	616-25-1	0.51±0.05d	0.48±0.04d	0.54±0.03cd	0.66±0.04c	0.71±0.13b	0.94±0.06a
α-Terpineol	11.576	1688	98-55-5	31.73±4.18d	57.77±3.84b	11.77±0.45e	117.33±8.08a	56.07±7.23b	23.40±0.53c
Epi-Cubenol	14.124	2067	19912-67-5	1.00±0.12d	4.31±0.48b	0.92±0.02d	0.78±0.07d	7.27±0.73a	0.87±0.02d
Hotrienol	10.683	1603	29957-43-5	1.39±0.16d	18.13±1.42b	4.82±0.11c	22.93±1.74a	15.77±1.86b	2.96±0.09c
Nerol	12.451	1797	106-25-2	5.45±0.89b	1.66±0.17d	4.01±0.19c	4.15±0.34c	1.88±0.31d	2.02±0.10d
1-Pentanol	5.307	1250	71-41-0	32.23±2.06c	41.67±4.66b	30.77±2.54c	28.13±1.67c	56.70±8.41a	27.33±2.39c
1-Phenylethanol	12.552	1821	98-85-1	0.89±0.12d	1.47±0.09b	2.49±0.09a	0.94±0.05d	2.73±0.38a	5.39±0.61a
Cis-Nerolidol	13.967	2044	142-50-7	1.56±0.22d	4.89±0.47a	2.97±0.23c	1.41±0.13d	3.18±0.33c	2.75±0.09c
Isogeraniol	12.534	1820	5944-20-7	0.88±0.14c	1.27±0.10b	1.32±0.07b	0.91±0.08c	1.29±0.14b	1.90±0.06a
4-Hexen-1-Ol	7.346	1391	928-92-7	0.49±0.05d	0.70±0.07c	1.77±0.11a	2.02±0.10a	1.63±0.37a	1.87±0.15a
1-Decanol	12.111	1760	112-30-1	0.40±0.09b	0.35±0.01b	0.32±0.02b	1.20±0.11a	0.52±0.08b	0.31±0.01b
Nonan-1-Ol	11.233	1660	143-08-8	3.70±0.52b	2.70±0.21c	2.13±0.09cd	1.56±0.11d	2.79±0.37c	4.42±0.26a
1-Heptanol	8.438	1453	111-70-6	7.00±0.93b	5.07±0.14c	4.92±0.30c	3.88±0.17d	6.77±0.83b	9.79±0.36a
Menthol	14.445	1644	2216-51-5	7.14±1.58bc	7.39±0.80b	6.23±0.30c	4.34±0.35d	14.70±2.07a	6.52±0.19c
Alkenes
(+/-)-Limonene	4.609	1199	138-86-3	10.74±1.68d	33.87±3.93b	9.68±0.63d	53.97±2.66a	25.97±7.33c	8.50±0.47d
Terpinolene	5.836	1281	586-62-9	7.98±0.99c	20.63±1.33a	4.53±0.21d	47.53±2.50a	16.27±2.37b	6.75±0.25c
γ-Terpinene	5.152	1238	99-85-4	11.61±1.48a	9.55±0.77b	7.28±0.34c	13.97±1.12a	8.72±1.66b	3.30±0.17d
Calamenene	12.714	1839	72937-55-4	11.37±1.18c	45.77±4.25a	7.72±0.37d	6.89±0.51d	62.70±5.98a	7.45±0.48d
Longicyclene	9.095	1519	1137-12-8	3.77±0.25d	8.39±0.79b	10.31±0.60a	7.53±0.89bc	7.49±1.23bc	3.91±0.41d
α-Cubebene	8.516	1463	31141-66-9	5.54±0.68c	14.77±1.37a	1.79±0.09d	1.45±0.11d	20.97±2.16a	1.75±0.04d
(3E)-β-Ocimene	5.392	1250	13877-91-3	11.05±1.39c	23.43±1.59b	16.37±0.67b	40.37±2.36a	15.33±1.17b	8.34±3.56c
α-Terpinene	4.348	1178	99-86-5	7.83±0.97b	8.87±0.94a	5.61±0.45d	12.73±0.50a	8.35±2.42b	2.88±0.04e
β-Pinene	4.155	1116	127-91-3	16.10±4.69c	26.40±7.63b	25.37±0.45b	36.87±1.75a	22.13±7.76b	12.41±4.39d
Copaene	9.714	1492	3856-25-5	0.42±0.06c	1.04±0.09a	0.42±0.02c	30.13±1.76a	1.29±0.13a	14.93±0.91b
α-Corocalene	14.15	2060	20129-39-9	0.25±0.04c	1.31±0.13a	0.15±0.01d	0.15±0.02d	2.09±0.19a	0.14±0.01d
α-Phellandrene	4.767	1167	99-83-2	0.42±0.03b	0.49±0.01a	0.45±0.01b	0.66±0.06a	0.40±0.28b	0.27±0.01c
Acids
Nonanoic Acid	14.655	2171	112-05-0	18.17±3.49b	24.47±1.94a	15.93±1.65c	8.79±0.81d	15.43±2.67c	19.87±0.90b
Caproic Acid	12.797	1846	142-62-1	24.13±3.23c	38.57±1.82a	24.87±2.05c	16.37±0.93d	29.90±4.97b	35.70±1.90a
Geranic Acid	15.478	2347	459-80-3	8.00±1.39b	7.06±0.48c	43.50±2.42a	8.28±0.54b	6.86±1.35c	5.42±0.08d
Heptanoic Acid	13.488	1950	111-14-8	16.47±3.30a	14.83±0.80b	13.60±0.72c	5.37±0.31e	11.72±2.02d	15.63±0.68b
Octanoic Acid	14.101	2060	124-07-2	7.67±1.29c	10.36±1.23a	5.62±0.30d	5.14±0.59d	10.03±1.77a	9.03±0.52b
Benzoic Acid	16.048	2414	65-85-0	2.32±0.33d	5.25±0.53a	3.78±0.43b	3.08±0.99c	6.27±1.46a	3.64±0.31bc
2-Ethylbutyric Acid	11.673	1711	32391	39.30±3.95c	59.40±4.45b	43.27±4.64c	33.77±1.46d	70.43±9.90a	41.60±1.44c
Pyrazines
2,3-Dimethylpyrazine	6.729	1344	5910-89-4	3.46±0.36c	11.43±0.72a	5.32±0.45b	4.08±0.19c	5.30±1.00b	1.88±0.15d
2-Ethylpyrazine	6.56	1337	13925-00-3	3.55±0.32d	17.83±1.27a	11.53±0.90b	5.53±0.30d	9.66±1.52c	3.14±0.37d
2,5-Dimethylpyrazine	6.364	1320	123-32-0	69.60±6.05d	236.33±12.50a	184.33±11.93b	85.10±4.51d	143.33±19.86c	56.63±3.55e
2,6-Dimethylpyrazine	6.454	1328	108-50-9	18.83±1.82c	99.27±5.62a	62.00±4.73b	27.53±1.33c	53.27±7.05b	18.33±1.39c
2,6-Diethylpyrazine	8.088	1445	13067-27-1	0.83±0.11b	2.99±0.21a	1.31±0.12b	0.70±0.03c	1.14±0.18b	0.30±0.03d
2,3,5-Trimethylpyrazine	7.597	1395	14667-55-1	18.33±2.29c	39.00±2.96a	20.40±1.35c	10.97±0.59d	16.93±2.66c	6.35±0.33e
3-Ethyl-2,5-Dimethylpyrazine	8.238	1435	13360-65-1	76.70±9.44d	223.67±15.04a	128.33±8.33b	58.00±2.86e	116.67±16.50b	34.40±1.65f
2-Methylpyrazine	5.542	1266	109-08-0	9.44±0.67d	58.87±3.61a	37.90±3.29b	19.83±1.27c	34.50±6.24b	13.17±1.02c
2-Ethyl-5-Methylpyrazine	7.424	1383	13360-64-0	48.73±28.26c	178.00±10.82a	130.67±8.74b	63.00±3.20c	76.90±37.10c	26.77±12.55d
2,5-Diethylpyrazine	8.989	1456	13238-84-1	2.41±0.34c	6.69±0.57a	3.21±0.24b	1.55±0.09d	2.71±0.43bc	0.63±0.03e
2,3-Diethyl-5-Methylpyrazine	9.319	1486	18138-04-0	1.14±0.18c	2.93±0.17a	1.22±0.08c	0.75±0.06d	1.11±0.18c	0.27±0.02e
Acetylpyrazine	10.848	1631	22047-25-2	0.41±0.05c	1.37±0.10a	0.81±0.04b	0.37±0.02c	0.79±0.10b	0.47±0.02c
3,5-Diethyl-2-Methylpyrazine	9.273	1508	18138-05-1	3.65±0.55b	6.57±0.56a	2.71±0.21c	1.74±0.09d	2.52±0.39c	0.62±0.02e
Furans
2-Ethylfuran	2.152	951	3208-16-0	2.03±0.23c	2.52±0.17b	2.22±0.21c	1.87±0.11c	2.56±0.42b	3.26±0.22a
2-Acetylfuran	9.205	1499	1192-62-7	18.27±1.67d	98.30±5.57a	60.03±4.20b	40.27±2.57c	60.10±8.15b	20.37±1.47d
2-Pentylfuran	5.098	1232	3777-69-3	51.87±8.04c	58.57±2.91b	43.63±2.77d	35.07±1.69e	48.33±5.25c	66.10±5.21a
2-(2-Pentenyl) Furan	6.142	1282	70424-14-5	1.00±0.12d	1.83±0.13a	1.18±0.10c	1.62±0.10b	1.55±0.23b	2.07±0.15a
2-Methylfuran	1.848	870	534-22-5	0.74±0.06c	1.16±0.08b	1.64±0.14a	0.77±0.03c	1.30±0.23b	1.34±0.08b
Pyrroles
1-Furfurylpyrrole	12.684	1824	1438-94-4	0.37±0.04c	2.63±0.21a	1.35±0.14b	0.58±0.05c	0.64±0.12c	0.04±0.03d
2-Acetylpyrrole	13.606	1973	1072-83-9	16.03±2.18d	56.20±3.26a	39.67±1.38b	22.17±1.38c	43.43±5.17b	9.23±0.32e
Miscellaneous
Vanillin	16.716	2569	121-33-5	5.89±1.08c	18.77±0.72a	9.84±0.73b	11.90±0.36ab	11.43±1.01b	12.80±0.30a
1,1,6-Trimethyl-1,2-Dihydronaphthalene	12.016	1737	30364-38-6	6.97±0.94b	11.03±0.83a	6.25±0.47c	7.13±0.49b	6.23±0.90c	1.32±0.07d
Toluene	2.8	1042	108-88-3	7.39±0.53c	16.60±1.51a	9.25±0.65b	9.80±0.52b	10.57±2.06b	4.46±0.42d
Naphthalene	11.971	1745	91-20-3	11.33±1.25bc	13.60±2.25ab	12.67±1.00b	15.40±1.40a	13.73±1.55ab	8.51±0.68c
Ethylbenzene	3.693	1129	100-41-4	0.95±0.07b	1.31±0.24a	1.23±0.03a	0.99±0.02b	1.38±0.22a	0.77±0.07c
2,4-Di-Tert-Butylphenol	15.327	2321	96-76-4	119.87±19.69a	108.67±8.33b	102.30±4.10b	139.67±15.18a	81.97±5.66c	59.70±1.44d
Tridecane	6.613	1300	629-50-5	0.60±0.07c	0.85±0.06a	0.75±0.04b	0.64±0.05c	1.20±0.35a	0.58±0.03c
Tetradecane	8.255	1400	629-59-4	2.91±0.33c	5.11±0.39a	4.73±0.37a	4.95±0.24a	4.38±0.51b	2.94±0.09c
P-Cymene	5.665	1272	99-87-6	8.26±0.89c	11.23±0.96b	7.27±0.36d	15.47±1.01a	8.39±1.42c	3.61±0.25e
Fluorene	15.568	2337	86-73-7	0.76±0.14c	1.37±0.15a	0.89±0.05b	0.62±0.04c	1.24±0.13a	0.81±0.03b
Hexadecane	10.574	1600	544-76-3	1.61±0.21c	2.65±0.23a	2.52±0.16a	1.95±0.16b	3.14±0.31a	1.76±0.09c
O-Xylene	4.416	1183	95-47-6	3.04±0.29c	4.51±0.66a	3.61±0.13b	2.49±0.12d	4.06±0.39ab	2.27±0.23d
Indole	16.054	2469	120-72-9	9.96±1.46c	26.23±2.05a	17.77±0.59b	10.32±0.73c	10.97±1.65c	17.47±0.42b
Pentadecane	9.203	1500	629-62-9	1.47±0.27c	1.88±0.21b	1.93±0.22b	1.64±0.06bc	2.19±0.16a	1.15±0.04d
Skatole	16.3	2515	83-34-1	0.90±0.15c	1.34±0.11a	0.87±0.05c	1.27±0.08ab	0.71±0.09d	0.43±0.01e
Eugenol	14.683	2169	97-53-0	0.26±0.05d	0.94±0.07a	0.32±0.01cd	0.32±0.02cd	0.63±0.08b	1.40±0.02a
Coumarin	16.131	2465	91-64-5	2.53±0.33d	38.13±2.56a	7.90±0.22c	3.50±0.17d	8.50±0.69c	13.90±0.44b

Table 2. Aroma compounds with an ROAV >1 in 6 different tea cultivars.

Metabolite	CAS ID	Threshold (μg/L or μg/kg)	HJC1	CC4H	GZSC	QM601	SLX	SMCY
Nonanal	124-19-6	1.1	25.67±4.42	29.58±2.58	18.48±0.73	12.06±0.14	18.12±2.09	25.15±0.82
Hexanal	66-25-1	4.5	1.21±0.18	1.33±0.09	1.13±0.06	0.80±0.05	1.10±0.06	1.38±0.08
β-Cyclocitral	432-25-7	3	2.49±0.30	3.73±0.44	3.92±0.27	3.42±0.21	4.02±0.66	3.26±0.12
Benzaldehyde	100-52-7	0.024	3475.00±421.33	3577.78±187.33	2804.17±147.96	6986.11±479.32	3565.28±497.94	4512.50±309.49
2-Methylbutyraldehyde	96-17-3	1.5	11.42±1.12	6.75±0.27	7.28±0.68	31.24±2.01	12.16±2.04	4.20±0.33
Octanal	124-13-0	0.8	5.89±0.97	6.85±0.60	3.78±0.27	2.60±0.04	4.22±0.62	6.29±0.33
Heptanal	111-71-7	2.8	4.20±0.71	3.48±0.32	3.26±0.18	1.51±0.02	2.90±0.36	3.11±0.23
Tetradecanal	124-25-4	67	1.16±0.14	0.35±0.03	0.41±0.02	0.15±0.00	1.64±0.12	0.44±0.00
Safranal	116-26-7	3	3.28±0.38	3.93±0.40	3.90±0.23	3.09±0.24	3.67±0.51	3.64±0.18
Isovaleraldehyde	590-86-3	0.5	11.12±1.26	2.22±0.08	2.51±0.20	10.22±0.62	6.81±1.15	5.17±0.39
Decanal	112-31-2	3	0.81±0.21	0.87±0.01	0.70±0.04	0.56±0.02	1.01±0.33	0.70±0.17
1-Octen-3-One	4312-99-6	0.003	584.44±84.74	840.00±87.43	654.44±55.21	531.11±59.66	947.78±110.02	998.89±57.48
Jasmone	488-10-8	1.9	1.82±0.27	10.63±0.92	3.57±0.11	6.14±0.51	7.91±0.97	16.23±0.21
β-Ionone	79-77-6	0.021	1315.87±174.60	963.49±116.87	931.75±48.64	836.51±9.91	1109.52±127.86	963.49±9.91
2,3-Octanedione	585-25-1	12	2.29±0.23	2.61±0.17	1.89±0.35	2.25±0.11	3.25±0.64	2.29±0.14
Damascenone	23726-93-4	0.006	53.17±8.49	92.72±5.59	103.06±4.10	51.67±3.18	111.56±13.68	31.67±1.17
(E)- β-Damascone	23726-91-2	0.001	616.33±113.46	995.33±133.81	2245.00±3399.39	4166.67±259.29	1266.67±127.02	5253.33±122.20
(E, E)-3,5-Octadien-2-One	38284-27-4	0.1	33.83±3.60	86.10±6.20	60.37±2.06	79.67±4.26	61.37±8.02	110.33±7.02
Methyl Salicylate	119-36-8	40	0.75±0.10	1.55±0.17	2.34±0.13	1.75±0.12	2.80±0.36	1.64±0.05
Linalyl Acetate	115-95-7	0.1109	4.02±0.32	62.43±5.32	12.71±0.87	33.54±2.72	23.29±2.59	21.67±1.01
Methyl Nonanoate	1731-84-6	0.04	1.97±0.22	4.27±0.23	3.46±0.22	4.63±0.08	3.44±0.41	9.64±0.49
Phenylethyl Alcohol	20-12-8	564.23	1.21±0.09	0.75±0.03	0.87±0.02	0.79±0.03	0.67±0.06	1.36±0.02
Geraniol	106-24-1	6.6	15.94±2.18	9.24±0.80	27.17±1.22	10.09±0.71	10.19±1.28	13.35±0.38
Linalool	78-70-6	6	12.11±1.39	18.83±1.04	7.04±0.33	43.56±1.87	24.00±3.25	24.56±1.21
1-Octen-3-Ol	3391-86-4	1.5	13.13±1.63	19.40±2.31	15.56±1.04	12.87±0.66	18.62±2.90	17.53±1.01
(3E)-β-Ocimene	13877-91-3	0.02	552.50±69.60	1171.67±79.43	818.33±33.29	2018.33±118.15	766.67±58.59	417.17±178.18
α-Phellandrene	99-83-2	0.04	10.61±0.73	12.28±0.28	11.23±0.37	16.57±1.61	9.95±7.11	6.72±0.32
3-Ethyl-2,5-Dimethylpyrazine	13360-65-1	25	3.07±0.38	8.95±0.60	5.13±0.33	2.32±0.11	4.67±0.66	1.38±0.07
2-Ethyl-5-Methylpyrazine	13360-64-0	16	3.05±1.77	11.13±0.68	8.17±0.55	3.94±0.20	4.81±2.32	1.67±0.78
2,5-Diethylpyrazine	13238-84-1	0.02	120.33±17.22	334.67±28.25	160.50±12.13	77.67±4.54	135.50±21.50	31.28±1.42
2,3-Diethyl-5-Methylpyrazine	18138-04-0	0.031	36.76±5.91	94.62±5.49	39.35±2.64	24.13±1.87	35.86±5.90	8.68±0.50
3,5-Diethyl-2-Methylpyrazine	18138-05-1	0.26	14.03±2.13	25.27±2.15	10.44±0.81	6.68±0.36	9.71±1.49	2.38±0.09
2-Pentylfuran	3777-69-3	5.8	8.94±1.39	10.10±0.50	7.52±0.48	6.05±0.29	8.33±0.91	11.40±0.90
P-Cymene	99-87-6	11.4	0.72±0.08	0.99±0.08	0.64±0.03	1.36±0.09	0.74±0.12	0.32±0.02
Indole	120-72-9	11	0.91±0.13	2.38±0.19	1.62±0.05	0.94±0.07	1.00±0.15	1.59±0.04
Coumarin	91-64-5	11	0.23±0.03	3.47±0.23	0.72±0.02	0.32±0.02	0.77±0.06	1.26±0.04

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