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Lushan Yunwu tea (LSYWT) is a famous green tea in China. However, the effects of intercropping tea with flowering cherry on the overall aroma of tea have not been well understood. In this study, headspace solid-phase microextraction (HS-SPME) coupled with gas chromatography–mass spectrometry (GC–MS) was used for analysis. A total of 54 volatile compounds from eight chemical classes were identified in tea samples from both the intercropping and pure-tea-plantation groups. Principal component analysis (PCA), orthogonal partial least-squares discriminant analysis (OPLS-DA), and odor activity value (OAV) methods combined with sensory evaluation identified cis-jasmone, nonanal, and linalool as the key aroma compounds in the intercropping group. Benzaldehyde, α-farnesene, and methyl benzene were identified as the main volatile compounds in the flowering cherry using headspace solid-phase microextraction/gas chromatography–mass spectrometry (HS-SPME/GC–MS). These findings will enrich the research on tea aroma chemistry and offer new insights into the product development and quality improvement of LSYWT. [ABSTRACT FROM AUTHOR]

Volatile compounds including terpenes, aldehyde, phenol, and alcohol are significantly contributed floral and fruity aromas to the Muscat variety. 'Ruidu Hongyu' grapevine is one of the newly developed grape varieties, and cultivation of this variety has been extended across China due to unique quality traits and taste. In this study, HS-SPME/GC-MS and transcriptome sequencing analysis were performed to evaluate the impact of exogenous 2,4-epibrassinolide (EBR), jasmonic acid (JA), and their signaling inhibitors brassinazole (Brz)/sodium diethyldithiocarbamate (DIECA) on the biosynthesis of aroma substances in 'Ruidu Hongyu' grapevine. According to the results, exogenous BR and JA promoted the accumulation of various aroma substances, including hexenal, 2-hexenal, nerol oxide, vanillin, hotrienol, terpineol, neral, nerol, geraniol, and geranic acid. After EBR and JA treatments, most of the genes responsible for terpene, aldehyde, and alcohol biosynthesis expressed at a higher level than the CK group. Relatively, EBR treatment could not only promote endogenous BR biosynthesis and metabolism but also elevate BR signaling transduction. JA treatment contributed to endogenous JA and MeJA accumulation, as well. Through transcriptome sequencing, a total of 3043, 903, 1470, and 607 DEGs were identified in JA vs. JD, JA vs. CK, BR vs. CK, and BR vs. Brz, respectively. There were more DEGs under both EBR and JA treatments at late fruit ripening stages. The findings of this study increase our understanding regarding aroma substances biosynthesis and endogenous BR/JA metabolism in response to exogenous EBR and JA signals. [ABSTRACT FROM AUTHOR]

BACKGROUND Keemun black tea (KBT) is one of the most popular tea beverages in China as a result of its unique flavor and potential health benefits. The geographical origin of KBT influences its quality and price. The present study aimed to apply a head‐space solid phase microextraction approach and gas chromatography–mass spectrometry combined with chemometric analysis to profile the volatile compounds of KBT collected from five production areas. RESULTS: Thirty‐one peaks were detected in 61 KBT samples. Hierarchical cluster analysis, principal component analysis (PCA), k‐nearest neighbor (k‐NN) and stepwise linear discriminant analysis (SLDA) were employed to visualize the volatile fractions. The results of unsupervised statistical tools were compared using a test for similarities and distinctions, which showed that different sources may be associated. A satisfying combination of average recognition (91.7%) and cross‐validation prediction abilities (84.6%) was obtained for the PCA–k‐NN. Among all of the statistical tools, SLDA provided promising results, with 100% recognition and 96.4% prediction ability. CONCLUSION: The results obtained in the present study indicate that the volatile compounds can be used as indicators to identify the geographical origin of KBT. © 2019 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

• Geographic markers in raw rice were involved in secondary metabolism pathways. • Most of geographic markers in cooked rice were lipid oxidation products. • Samples from Southern China contained more lipid oxidation products. Japonica rice is widely planted in different regions of China. Rice of different geographical origins may have substantially different economic values. In this study, An untargeted metabolomics based approach using headspace solid-phase microextraction coupled to gas chromatography-mass spectrometry (HS-SPME/GC-MS) was applied to distinguish 27 japonica rice varieties originated from South, Northern and Northeastern China in raw and cooked form, respectively. Orthogonal partial least-squares discriminant analysis (OPLS-DA) models exhibited good geographic discrimination. Sixteen and twenty-two volatiles were selected as the discriminant markers in raw and cooked rice, respectively. However, only hexanal, 3,5-octadien-2-one and 2-butyl-2-octenal were selected both in raw and cooked rice. Markers in raw rice mainly involved in terpenes, lipoxygenases, indole, and shikimate and benzoic acid pathways. Markers in cooked rice were mainly derived from lipid oxidation. The results provided a deeper understanding of volatiles variation of rice in China from different geographic origins. [ABSTRACT FROM AUTHOR]

Cannabis sativa L., has gained increasing attention due to its potential applications in various fields. However, the compositions of hemp seeds from different producing regions are quite different, significantly affects resource utilization. This work conducted the regional differentiation of hemp seeds from Dongbei, Guangxi, Inner Mongolia and Shanxi in China based on the headspace solid phase micro-extraction coupled with gas chromatography-mass spectrometry (HS-SPME/GC-MS) and multivariate analysis. Moreover, the chemical composition, amino acid and fatty acid profiles of hemp seeds and antioxidant activities of hemp protein isolate were evaluated from above four producing regions. The results showed that hemp seeds had large amounts of fat (24.30-34.65%) and protein (21.87-23.40%) with ideal amino acid and fatty acid profiles and large amounts of volatiles. More than 300 volatile compounds were detected, and 35 key contributors to the unique aroma were finally identified out of 110 volatile compounds with odor activity values (OAVs), including 14 aldehydes, 2 ketones, 4 alcohols, 2 esters, 1 acid, 3 aromatics, 5 terpenes and 4 other compounds. The content of alcohols in all hemp seeds was highest and 16 unique volatiles only found in hemp seeds from Shanxi. Meanwhile, the VIP scores indicated that acetic acid, hexanal, hexan-1-ol and eucalyptol contributed the most to the difference among groups. According to the results of fuzzy comprehensive evaluation, the hemp seeds from Shanxi seemed to have the better quality. Therefore, multivariate analysis combined with HS-SPME/GC-MS could effectively distinguish hemp seeds from different producing regions, and thus decipher the geographical characteristics of raw materials., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier Ltd.)

Pine-mushrooms is rich in bioactive compounds, possess a unique aroma profile for culinary art. In China, pine-mushroom has been produced in Southwest and Northeast area. However, the discrepancy of volatile profiles in pine-mushrooms from two regions was unclear due to different extraction and detection method applied in research. This study attempted to compare the volatile profiles of four pine-mushrooms from Southwest (LS) and Northeast (HEB, SY, MDJ) using Headspace Solid Phase Microextraction coupled with Gas Chromatography Mass Spectrometry (HS-SPME/GC-MS) and Electronic nose (E-nose). Results showed a significant difference in aroma profiles among samples. A total of 100 volatile compounds were identified, and separated into 11 classes. Benzaldehyde and hexanal were detected in all samples, which could be the pivotal aroma components in pine-mushrooms. Aromatic components, were present in LS pine-mushroom from Southwest China, including abundant of methyl (Z)-N-hydroxybenzenecarboximidate, benzaldehyde, and methyl 3-phenylprop-2-enoate. Meanwhile, some alcohols (such as oct-1-en-3-ol, hexan-1-ol) were characteristic compounds present in HEB, SY and MDJ samples. Principal component analysis (PCA) of E-nose data showed a clear distinction among samples. In addition, this study also highlighted the correlation between key volatile compounds detected by GC-MS and E-nose sensors, which could be benefit for further explanation to the origin of differences in sensory quality of pine-mushrooms. [Display omitted] • The discrepancy of volatile profile in four kinds of pine-mushroom was determined. • Aromatics were characteristic compounds present in Southwest China pine-mushroom. • Some alcohols and alkanes were feature compounds present in Northeast area. • PCA of E-nose data showed a clear distinction among samples. • Uncovered the correlation between key compounds detected by GC-MS and E-nose. [ABSTRACT FROM AUTHOR]

• Two kinds of grafted pine nuts showed different behavior during roasting. • Roasting conditions significantly affected volatile compounds of pine nut. • D-limonene was the most abundant volatile in both raw grafted pine nuts. • Roasting duration at high temperature had less impact on aroma profiles. • GC–MS performed better separation compared to E-nose for discriminating the samples. As an attempt to fulfill the massive demand for pine nuts, two grafted trees were cultivated: grafted Pinus koraiensis on the same scions (PK) and grafted Pinus koraiensis on Pinus sylvestris rootstocks (PKS) trees. Both PK and PKS are acknowledged as important economic trees in the northeastern area of China. This study aimed to compare the volatile compounds and aroma profiles in PK and PKS by Headspace Solid Phase Microextraction (HS-SPME) coupled with Gas Chromatography-Mass Spectrometry (GC–MS) and Electronic nose (E-nose) as responses to different roasting conditions. The results showed that a total of 286 volatile compounds were identified in the PK and PKS samples, which some of them were considered to contribute to the desirable aroma of samples. Abundance of terpenes and aromatic hydrocarbons, such as D-limonene and toluene, were respectively present in both raw PK and PKS. The increasing temperature and duration of roasting significantly decreased terpenes and aromatic hydrocarbons content, while more alkanes/alkenes, acids, and ketones were generated in the medium temperature condition. The late phase of roasting was dominated by aldehydes, furans, furfurals, pyrazines, and pyrroles, for which PKS showed a higher content than PK. The aroma profiles detected by E-nose showed that the influence of roasting time was less at high temperatures than those at low and medium temperatures. This study also highlighted the feasibility of principal component analysis (PCA) combined with HS-SPME/GC–MS and E-nose to discriminate the samples. [ABSTRACT FROM AUTHOR]

This study aimed to develop a potential analytical method to discriminate the Chinese winter wheat according to geographical origin and cultivars. A total of 90 wheat samples of 10 different wheat cultivars among three regions were examined by headspace solid phase microextraction coupled with gas chromatography-mass spectrometry (GC-MS). The peak areas of 32 main volatile compounds were selected and subjected to statistical analysis, which revealed significant differences among different regions and cultivars. Multivariate analysis of variance showed a significant influence of regions, wheat genotypes, and their interaction on the volatile composition of wheat. Principal component analysis of the aromatic profile showed better visualization for wheat geographical origins. Finally, a classification model based on the linear discriminant analysis was successfully constructed for the discrimination of regions and cultivars with the correct classification percentages of 90 and 100%, respectively., (© 2019 John Wiley & Sons, Ltd.)