Flavor fingerprinting and aroma-active compound evolution in prune preserves: Comparative analysis of drying technologies by GC-MS and GC-IMS.

Impact of aroma-enhancing microorganisms on aroma attributes of industrial Douchi: An integrated analysis using E-nose, GC-IMS, GC–MS, and descriptive sensory evaluation

Characterization of the aroma profiles of oolong tea made from three tea cultivars by both GC–MS and GC-IMS

This study combined gas chromatography-ion mobility spectrometry (GC-IMS) and multivariate statistical analysis to explore the differences in the characteristic aroma of Idesia polycarpa Maxim (I. polycarpa) fruit and oil under different drying methods: natural drying (ND), hot air drying (HAD), microwave drying (MD), and microwave vacuum drying (MVD). The results revealed that 91 volatile compounds were identified in the fruit, and 82 were found in the oil of I. polycarpa. HAD and MD resulted in the most significant loss of volatile aroma in both the fruit and oil. In contrast, MVD demonstrated the best retention of these volatile aromas. Multivariate statistical analysis and odor activity value (OAV) analysis (OAV ≥ 1) were employed to identify 10 volatile aroma compounds considered differentiating factors in the fruit and oil subjected to different drying methods. These compounds, including hexanal, 3-methylbutyric acid, 2-acetylpyridine, guaiacol, valeraldehyde, and butyric acid, significantly contribute to the flavor characteristics of I. polycarpa fruit and oil, evoking notes of nuts, caramel, and sourness. The OAVs of these aroma-differentiating compounds in microwave vacuum-dried fruit and oil were higher compared to those from other drying methods. Therefore, when considering the enhancement of volatile flavor compounds, MVD is more effective than the other drying methods in promoting the formation of flavor compounds in I. polycarpa fruit and oil.

Ginseng (Panax ginseng C. A. Meyer) is a valuable plant resource which has been used for centuries as both food and traditional Chinese medicine. It is popular in health research and markets globally. Fresh ginseng has a high moisture content and is prone to mold and rot, reducing its nutritional value without proper preservation. Drying treatments are effective for maintaining the beneficial properties of ginseng post-harvest. In this study, we investigated the effects of natural air drying (ND), hot-air drying (HAD), vacuum drying (VD), microwave vacuum drying (MVD), and vacuum freeze drying (VFD) on volatile organic compounds (VOCs) in ginseng. The results showed that the MVD time was the shortest, followed by the VFD, VD, and HAD times, whereas the ND time was the longest, but the VFD is the most beneficial to the appearance and color retention of ginseng. A total of 72 VOCs were obtained and 68 VOCs were identified using the five drying methods based on gas chromatography-ion mobility spectrometry (GC-IMS) technology, including 23 aldehydes, 19 alkenes, 10 alcohols, 10 ketones, 4 esters, 1 furan, and 1 pyrazine, and the ND method was the best for retaining VOCs. GC-IMS fingerprints, principal component analysis (PCA), Euclidean distance analysis, partial least squares discriminant analysis (PLS-DA), and cluster analysis (CA) can distinguish ginseng from different drying methods. A total of 29 VOCs can be used as the main characteristic markers of different drying methods in ginseng. Overall, our findings provide scientific theoretical guidance for optimizing ginseng's drying methods, aromatic health effects, and flavor quality research.

To investigate the impact of microencapsulation on the volatile organic compounds (VOCs) in Zanthoxylum oil, this study compared unencapsulated Zanthoxylum oil (ZO) with microencapsulated Zanthoxylum oil (MZO) using physicochemical analysis, sensory evaluation, and molecular sensory analysis. Sensory evaluation revealed significant differences in aroma attributes between ZO and MZO, whereas no notable differences were observed in numbing intensity or overall acceptability. Colorimetric analysis indicated significant distinctions between the two samples. Electronic nose (E-nose) analysis demonstrated a reduction in overall aroma intensity for MZO compared to ZO. Gas chromatography-mass spectrometry (GC-MS) identified 43 VOCs, including 22 compounds present in both samples, accounting for 46.8% of the total. Terpenes represented the predominant class in both ZO (69.7%) and MZO (68.2%). Comprehensive analysis based on odor activity value (OAV) and variable importance in projection (VIP) identified nine volatile compounds as key aroma contributors. Gas chromatography-ion mobility spectrometry (GC-IMS) detected 90 the volatile organic compounds (VOCs), with esters (30.38%) and heterocyclic compounds (10.42%) predominating in ZO, while esters (29.08%) and alcohols (26.12%) were predominant in MZO. Compared to ZO, MZO exhibited increased levels of alcohols (from 12.04% to 26.12%) and terpenes (from 1.39% to 3.53%), but decreased levels of acids (from 5.77% to 2.72%) and aldehydes (from 10.29% to 4.62%). This approach provides a comprehensive assessment of flavor quality before and after microencapsulation, offers a scientific basis for quality control, and facilitates the development and utilization of Zanthoxylum oil resources.

A prepared dish needs to be reheated before eating, and various reheating methods affect its flavor quality. This study evaluated the influence of stir-frying reheating, steaming reheating and microwave reheating on moisture content, lipid oxidation and flavor profiles of prepared beef with tangerine peel. Stir-frying reheating samples obtained a higher moisture content and the highest thiobarbituric acid reactive substance value. Fifty-seven volatile compounds were identified by gas chromatography–mass spectrometry, of which fifteen compounds were considered as odor-active compounds with an odor activity value > 1. Aldehydes were the most prominent contributors to the aroma of reheated samples. Results revealed that stir-frying reheating samples had the most varieties of odor-active compounds, and the odor activity values of most of them were relatively higher. The heatmap analysis based on the odor activity values indicated that the stir-frying reheating process could maintain the original flavor of samples. A total of fifty-two volatile organic compounds were identified by gas chromatography–ion mobility spectrometry, and the principal component analysis revealed that the three reheated samples could be well distinguished from each other. Moreover, the content of free amino acids and nucleotides in stir-frying reheating samples was higher than that in other reheated samples. In conclusion, different reheating treatments affected the flavor quality of beef samples, and stir-frying process was better to obtain the aroma and taste characteristics of samples. The results of this study could provide useful information about the appropriate reheating method of a dish of prepared beef with tangerine peel for consumers, caterers and industrial production.

This study evaluated the volatile organic compounds (VOCs) and taste properties of Gorgon Euryale seeds processed by five methods (steaming, boiling, microwaving, roasting, and stir-frying) using electronic tongue (E-tongue), electronic nose (E-nose), gas chromatography-mass spectrometry (GC-MS), and gas chromatography-ion mobility spectrometry (GC-IMS). A total of 44 and 40 VOCs were identified by GC-MS and GC-IMS, respectively. Pyrazines (2-ethyl-3,5-dimethylpyrazine, 2,3-diethyl-5-methylpyrazine) and furans (2-pentylfuran, 2-ethylfuran) played a major role in the baked aroma characteristics of roasted and stir-fried Gorgon Euryale seeds. Six and seven marker compounds were identified by Orthogonal Partial Least Square Discriminant Analysis (OPLS-DA) models for GC-MS and GC-IMS based on 12 VOCs with odor activity value>1 and 18 VOCs with relative odor activity value>0.1, respectively. OPLS-DA and principal component analysis score plots of the E-tongue and E-nose demonstrated that samples could be effectively distinguished in terms of flavor. This research provides a comprehensive basis for evaluating the impact of processing methods on the changes in flavor of Gorgon Euryale seeds. PRACTICAL APPLICATION: This work demonstrates that the use of E-tongue, E-nose, HS-SPME-GC-MS, and GC-IMS has the capability to thoroughly analyze the flavor profile of Gorgon Euryale seeds at both macro and micro levels. This approach effectively distinguishes Gorgon Euryale products subjected to different processing treatments and provides a reliable reference for evaluating and identifying the flavor quality of Gorgon Euryale seeds.

Citrus reticulata 'Chachi' peel (CRCP), which is named "Guangchenpi" in China, is a geographical indication product with unique flavor properties. CRCP has been used for centuries as a traditional genuine herb because of its excellent therapeutic effects. In addition, owing to its unique odor and high nutrition, it is widely used in various food preparations. Volatile organic compounds (VOCs) are regarded as an important quality marker for CRCP and are highly susceptible to effects in the drying process due to their thermal instability. In the current study, the main VOCs in CRCP were processed using different drying methods, including sun-drying, hot air drying, and vacuum-freeze drying. The VOCs were identified by the electronic nose (E-nose), gas chromatography-ion mobility spectrometry (GC-IMS), and headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS). The results showed that the CRCP dried by vacuum-freeze exhibited the highest VOCs contents and retained the richest compounds compared to those dried by other methods, which indicated that vacuum-freeze drying is the most suitable for CRCP production. Furthermore, the chemometrics analysis revealed that the primary differential metabolites of the samples generated using different drying methods were terpenes and esters. Overall, our study would help better understand the VOCs present in CRCP with different drying methods. The outcomes of the current study would guide the drying and processing of CRCP, which is beneficial for large-scale storage and industrial production of CRCP.

Multi-step screening of suitable Saccharomyces cerevisiae strain for lemon wine brewing

Comparative analysis of the differences in volatile organic components of three lavender essential oils in Ili region using sensory evaluation, GC-IMS and GC-MS techniques

Hotpot is a distinctive dish of East Asian cuisine, especially in China. Herein, headspace‐gas chromatography‐mass spectrometry, headspace‐gas chromatography‐ion mobility spectrometry, and sensory evaluation are applied to compare the volatile organic compounds (VOCs) of four types of hotpot seasoning oils (HSOs) and establish their characteristic fingerprints. A total of 203 VOCs are detected by gas chromatography‐mass spectrometry (GC‐MS). Among them, linalool, anethole, and estragole contribute to the overall aroma of all four HSOs (relative odor activity value ≥ 0.1). Gas chromatography‐ion mobility spectrometry (GC‐IMS) results reveal that 77 VOCs are identified, comprising 19 terpenoids, 18 aldehydes, 14 alcohols, 13 esters, 6 ketones, 3 acids, 2 furans, 1 pyrazine, and 1 sulfide. Meanwhile, principal component analysis demonstrates that GC‐IMS is an important tool for the rapid classification of hotpot seasonings. Finally, the sensory evaluation team concludes that the horse fat hotpot seasoning has promising development prospects. This study validates the applicability of GC‐IMS and GC‐MS for distinguishing VOCs in hotpots, and the findings provide a theoretical basis for flavor differentiation in HSOs.Practical Applications: Horse oil is significantly lower in cholesterol than butter, and thus possesses potential benefits for human health. This study provides a basis to produce horse oil hotpots and a reference for identifying the VOCs in HSOs.

Removal of fishy flavor in kelp (Laminaria japonica) by natural antioxidant soaking combined with microbial fermentation

Beiwudu Hulatang, a traditional Chinese culinary delicacy, is valued for its complex flavor profile; however, its characteristic aroma compounds and the determinants of sensory quality remain insufficiently studied. This study evaluated the flavor characteristics of four commercial samples and one laboratory-made sample of Beiwudu Hulatang using gas chromatography-ion mobility spectrometry (GC-IMS), electronic nose (E-nose), electronic tongue (E-tongue), and sensory evaluation. The results of E-tongue analysis indicated that bitterness and saltiness were the dominant taste attributes. E-nose analysis demonstrated strong responses to sulfur-containing compounds, alcohols, and alkanes, indicating their significant contribution to the overall aroma. A total of 60 volatile compounds were identified by GC-IMS, with ethers, alcohols, and terpenes being the most abundant chemical groups. Among these, 13 key aroma compounds were screened as discriminative markers (OAV > 1, VIP > 1) by integrating the odor activity value (OAV) and orthogonal partial least squares-discriminant analysis (OPLS-DA). The Pearson correlation analysis further revealed that sensory attributes, particularly aroma and overall acceptability, were positively correlated with propanal, heptaldehyde, and 1,8-cineol, and negatively correlated with linalool and limonene. Overall, this study provides a systematic characterization of the flavor profile of Beiwudu Hulatang and establishes a scientific basis for its quality standardization and flavor-oriented product development.

Characterization of the effect of different cooking methods on volatile compounds in fish cakes using a combination of GC–MS and GC-IMS

Aroma characteristics of traditional Huangjiu produced around Winter Solstice revealed by sensory evaluation, gas chromatography–mass spectrometry and gas chromatography–ion mobility spectrometry