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To investigate the changes in the quality of yak meat at different dry aging times (7, 14, 21, 28 and 35 d), in this study, sensory evaluation, texture analysis, and GC-IMS were employed to investigate the changes in texture and flavor of yak meat during different dry aging periods. Additionally, PLS-DA was utilized to identify the characteristic flavor compounds. The results showed that the dry aged 35 days sample exhibited the highest comprehensive score, with intact soft tissue structure and a favorable overall acceptability of aroma. The dry aging time had significant effects on the hardness, chewability, and adhesivity of yak meat (P

To investigate the effects of Angel yeast, Meyerozyma guilliermondii, Saccharomyces cerevisiae, Zygosaccharomyces rouxii and Candida parapsilosis fermentation on volatile flavour compounds in bean paste, the volatile flavour substances of fermented bean soup paste were analyzed by gas chromatography-ion mobility spectrometry (GC-IMS) technique using unfermented bean soup paste as a control group. The relative odour activity value (ROAV) method was used to determine the key flavour components. Principal component analysis (PCA) and partial least squares-discrimination analysis (PLS-DA) were used to comprehensively evaluate the aroma of fermented bean soup paste. A total of 50 volatile compounds were identified, which were primarily esters and alcohols in six fermented bean sauces. These compounds contribute to the distinct mellow, fruity, and malty flavour profiles characteristic of these sauces. The types and concentrations of volatile compounds in different fermented bean sauces exhibited statistically significant differences (P

A kind of Agriophyllum squarrosum bread (SMMB) was developed with Agriophyllum squarrosum flour and wheat flour as main raw materials. In this study, the formula of SMMB was optimized by single factor tests and response surface test. Then the texture, color and flavor of SMMB under optimized condition were compared with traditional bread (BMB) by using texture analyzer, colorimeter and gas chromatography-ionmobility spectrometry (GC-IMS). The results showed that when the proportion of Agriophyllum squarrosum flour in the mixed powder was 19.1%, and based on the total amount of mixed powder, adding of 2.5% yeast, 14.5% sugar, 10% butter, 1% edible salt, 0.5% ameliorant as well as 50% water, the SMMB was golden in color, full in shape, exquisite and uniform in internal organization, and had a unique flavor of Agriophyllum squarrosum. The SMMB also had the highest sensory score of 86.96 under the optimized condition. Compared with BMB, the color of SMMB was obviously different with decreased lightness, but increased redness and yellowness. The hardness, cohesion and elasticity were also increased in SMMB. The main flavor substances of the two types of bread were similar, but the contents of alcohols, aldehydes and ketones in SMMB were relatively higher, while the contents of esters and heterocyclic substances were lower than that of BMB. The different relative contents of flavor substances endowed SMMB with higher mellow, citrus, grass and malty flavor, while the flavor of ester, nutty and toasty was lower. This project would provide a theoretical basis for the application of Agriophyllum squarrosum in bread.

Cooking methods could have a great influence on the flavour of food, to investigate the effect of cooking methods on the aroma of pork, this study used electronic nose combined with gas chromatography-ion mobility spectrometry (GC-IMS) for multivariate statistical analyses of the volatile compounds in pork under different cooking methods. GC-IMS was used to characterise 100 volatile compounds (including monomers and dimers) of pork under different cooking methods. Finally, a stable model was established using orthogonal partial least squares discriminant analysis. Results showed that, the cooking method is crucial for the formation of pork flavour compounds. Pork cooked by oven roasting and air fryer methods contained characteristic volatile compounds such as ethyl (E)-2-hexenoate, 1-octen-3-ol, (Z)-4-decenal, 3-nonen-2-one, (E)-2-hexen-1-ol, propyl butyrate, furazanone, and dipentenyl-M, as compared to the two cooking methods of steaming and boiling. The air fryer method pork contained higher levels of (E)-ethyl 2-hexenoate, 1-octen-3-ol, (Z)-4-decenal, and 3-nonen-2-one than the oven-roasted pork. Valeraldehyde and ethyl acetate were labelled as characteristic volatile substance compounds for both steamed and boiled cooking styles, and the results from the electronic nose sensor showed that the RPCA model was effective in identifying volatile substances in pork for each cooking style. The results of the study revealed the effects of different cooking methods on the volatile components of pork and found that the aromas of air fryer preparation and oven roasting were more similar, providing some reference for the cooking and processing of pork.

The intelligent senses (Electronic nose and tongue), were combined with headspace gas chromatography-ion mobility spectrometry (HS-GC-IMS) and free amino acid were used in combination to determine the aroma and taste components during the processing of Chinese traditional dish Steamed beef with rice flour (SBD). The findings revealed that E-nose and E-tongue, could clearly distinguish and identify the aroma and taste of SBD. A total of 66 volatile substances and 19 free amino acids were identified by HS-GC-IMS and amino acid analyzer, respectively. The highest contribution to aroma in the production of SBD was alcohols, esters and aldehydes. Further analysis of relative odor activity showed that 3-Methylbutanol-D, 3-Methylbutanol-M and 3-Methylthio propanal is the marinating stage (T2) main aroma components. Ethyl 3-methylbutanoate-M and Ethyl 3-methylbutanoate-D were the main aroma components in the seasoning stage (T3). Additionally, the calculation of the taste activity value showed that Glutamic contributed significantly to the umami of SBD. Alanine was a representative taste component in the marinating stage (T2), while Proline, Aspartic, Lysine, Glutamic, Valine, Arginine, and Histidine were characteristic amino acids of the seasoning stage (T3). Consequently, this study offers valuable insights into the industrial-scale production and flavor regulation of SBD products.

In order to investigate the differences of volatile compounds in sprouted garlic, an electronic nose and trap headspace-gas chromatography-mass spectrometry (HS-Trap-GC-MS) combined with orthogonal partial least squares discriminant analysis (OPLS-DA), aroma activity value, differential heat map, and correlation analysis were employed to analyze the differences in volatile compounds of garlic sprouts at 0, 24, 48, 72 and 96 hours. A predictive model with a prediction accuracy of 96.00% was established by combining the electronic nose with OPLS-DA. GC-MS analysis revealed that sulfur compounds were the major common volatile compounds in garlic sprouts at different sprouting stages. The relative content of sulfur compounds showed a decreasing trend with the prolongation of sprouting time, while the variety exhibited an increasing trend. Allyl disulfide was the compound that experienced the most significant decrease in content during the sprouting process. Allyl tetrasulfide and allyl mercaptan were identified as common key compounds in the samples. Differential heat map analysis demonstrated that in addition to differences in the content of common substances, the absence of propyl sulfide, hexanal, di-tert-butyl dicarbonate, propenol, 6-methyl-2-heptyne, 5-methylthiadiazole, 2-ethy-1,3-dithiane, 2-prop-2-ynylsulfonylpropane, 2,5-dimethylthiophene, 2,5-dimethylfuran, 1-hexen-3-ol, and 1,3-dithiane further amplified the differences in odor between non-sprouted and sprouted garlic. The types of main common volatile compounds in sprouted garlic showed an increasing trend with the extension of sprouting time. There was a significant correlation between the major volatile compounds of garlic and most sensors of the electronic nose. The odor intensity of garlic gradually decreased with the prolongation of sprouting time.

The traditionally produced pea paste (PP) suffers from suboptimal flavor and inferior quality. Based on the study of single-strain fermentation, we further selected S. cerevisiae, Z. rouxii, and L. paracasei for PP production by dual-strain fermentation (SL, ZL). By combining intelligent sensory technology, gas chromatography–mass spectrometry (GC-MS), and ultra-high-performance liquid chromatography (UPLC) technology, the aroma and taste characteristics of SL- and ZL-fermented PP were compared. The electronic nose and tongue revealed the differences in the aroma and taste characteristics between the two fermentation methods for fermenting PP. In total, 74 volatile compounds (VOCs) in PP were identified through GC-MS analysis. In contrast, the number of VOCs and the concentrations of alcohols and acids compounds in SL were higher than in ZL. Among the 15 VOCs that were common to both and had significant differences, the concentrations of ethanol, 1-pentanol, and ethyl acetate were higher in SL. For taste characteristics, SL demonstrated significantly higher levels of sweet and bitter amino acids, as well as tartaric acid, compared with ZL. These results elucidate the flavor differences of dual-strain fermented PP, providing a theoretical basis for selecting suitable strains for fermenting PP.

The volatile substances among Malus toringoides (Rehd.) Hughes black tea，green tea and Kang brick tea were detected by electronic nose (E-nose), trap head space-gas chromatography-mass spectrometry (HS Trap GC-MS) and the differences of the volatile substances were analyzed by orthogonal partial least squares discriminant analysis (OPLS-DA), relative odor activity value (ROAV) and differential thermography in order to explore the odor differences of Malus toringoides (Rehd.) Hughes teas with three different processes. Result showed that E-nose could effectively distinguish three kinds of Malus toringoides (Rehd.) Hughes teas, and the prediction ability of the model established by E-nose combined with OPLS-DA was 95.70%. GC-MS analysis showed that aldehydes, esters and hydrocarbons were the main volatile substances, while alcohols were the main common volatile substances of black tea and green tea. The differences in the contents of aldehydes, esters, hydrocarbons and alcohols account for the variations in the aroma of Malus toringoides (Rehd.) Hughes teas produced by different processes. ROAV value combined with aroma type analysis showed that the volatile components of fruit aroma had a relatively large contribution to the formation of the odor of Malus toringoides (Rehd.). Isovaleraldehyde might be the key aroma substance to Malus toringoides (Rehd.) Hughes teas. Differential thermogram analysis showed that trimethoxyester, isovaleraldehyde and 2-ethylfuran were the main common volatile substances in Malus toringoides (Rehd.) Hughes teas.

To understand the effects of particle size on the extraction of volatile huajiao (HJ) Zanthoxylum oils, Hanyuan pepper powder of 20, 30, 40, 60, and 80 mesh sizes was fried at 130 ℃ for 20 minutes with rapeseed oil as the extract oil. E-nose, gas chromatography-ion mobility spectrometry (GC-IMS), gas chromatography-mass spectrometer (GC-MS), odor activity value (OAV), and quantitative descriptive analysis (QDA) were applied to analyze the volatile Zanthoxylum oil components extracted from different sizes of pepper particles. Cluster analysis and Pearson correlation were performed to explore the differences in aroma profiles between samples. The E-nose and CA results indicated that the HJ-1 (20 mesh) sample was clearly different from other samples in terms of aroma, the aroma characteristics of HJ-4 (60 mesh) and HJ-5 (80 mesh) samples were similar, and the aroma characteristics of HJ-2 (30 mesh) and HJ-3 (40 mesh) samples were similar to each other. A total of 118 aromatic components were detected by GC-IMS, comprising 20 unidentified components and 98 identified components. The identified compounds included 13 aldehydes, 11 ketones, 12 alcohols, 22 esters, 16 heterocycles, seven acid, two phenolic compounds, and eight miscellaneous components. Moreover, the OAV values of 14 key aromatic components were greater than 1, including linalool, 2-furanmethanol, 2-phenylethanol, linalyl acetate, methyl phenyl acetate, γ-terpinene, phellandrene, and β-pinene. The key aromatic components of the HJ-4 sample contributed the most to the aroma of Zanthoxylum oil. QDA analysis revealed that the HJ-4 samples had very strong woody, lemon, nutty and fatty flavors. The Pearson correlation coefficient showed that the sensory property of lemon, woody, nutty and fatty flavors and concentrations of most key aromatic were strongly and positively correlated. From comprehensive analysis, the HJ-4 sample prepared from 60 mesh pepper powder was determined to have the best aroma sensory quality. In conclusion, GC-IMS and OAV values were able to identify the effect of different sizes of pepper particles during the extraction of volatile components of Zanthoxylum oil. This information could be used to provide a theoretical and practical reference for the production of Zanthoxylum oil.

Three cooking methods of atmospheric steaming, high-pressure steaming and extrusion were used to make koji and fermented into quinoa sauce. The conventional physical and chemical indexes, volatile flavor substances and sensory quality of quinoa paste with different cooking methods were explored. Results showed that the extrusion group had the highest moisture content, total acid, amino acid nitrogen and reducing sugar, while the lowest pH and NaCl content in three groups. A total of 84 volatile substances were identified in quinoa sauce with three different cooking methods and the esters, aldehydes and acids were the main components of quinoa sauce. There were 73 volatile substances were detected in atmospheric steaming group and the furfural, acetic acid, phenylacetaldehyde and 9,12-octadecadienoic acid ethyl ester had higher relative content. In high-pressure steaming group, 60 volatile substances were detected and the relatively higher content of substances were furfural, acetic acid and 9,12-octadecadienoic acid ethyl ester. 39 Volatile substances were detected in extrusion group and the higher relative content components including furfural, acetic acid, 9,12-octadecadienoic acid ethyl ester, palmitic acid, ethyl palmitate and 2-methoxy-4-vinylphenol. Sensory evaluation of quinoa sauce with different cooking methods were carried out and the extrusion group had a moderate salty and sweet taste, full umami, unique flavor and higher popularity among the public. Therefore, extrusion was the optimum technique for making quinoa sauce among the three cooking methods. This study provides a theoretical basis for the processing of quinoa sauce.

This study aimed to investigate the volatile flavor compounds and tastes of six kinds of sauced pork from the southwest and eastern coastal areas of China using gas chromatography–ion mobility spectroscopy (GC-IMS) combined with an electronic nose (E-nose) and electronic tongue (E-tongue). The results showed that the combined use of the E-nose and E-tongue could effectively identify different kinds of sauced pork. A total of 52 volatile flavor compounds were identified, with aldehydes being the main flavor compounds in sauced pork. The relative odor activity value (ROAV) showed that seven key volatile compounds, including 2-methylbutanal, 2-ethyl-3, 5-dimethylpyrazine, 3-octanone, ethyl 3-methylbutanoate, dimethyl disulfide, 2,3-butanedione, and heptane, contributed the most to the flavor of sauced pork (ROAV ≥1). Multivariate data analysis showed that 13 volatile compounds with the variable importance in projection (VIP) values > 1 could be used as flavor markers to distinguish six kinds of sauced pork. Pearson correlation analysis revealed a significant link between the E-nose sensor and alcohols, aldehydes, terpenes, esters, and hetero-cycle compounds. The results of the current study provide insights into the volatile flavor compounds and tastes of sauced pork. Additionally, intelligent sensory technologies can be a promising tool for discriminating different types of sauced pork.

Salt is a key ingredient that can both enhance the taste and extend the shelf life of fermented vegetables. However, it is important to note that excessive salt levels can have adverse effects on consumer health. This study aimed to investigate the impact of various salt additions (2%, 4%, 6%, 8%, and 10% wt/wt) on the flavor profile of fermented ciba pepper, a traditional Chinese fermented chili sauce, using gas chromatography–ion mobility spectrometry (GC-IMS) in combination with an electronic nose (E-nose). Fermented ciba pepper samples were prepared with different salt additions: 2% (LJA), 4% (LJB), 6% (LJC), 8% (LJD), and 10% (LJE) (wt/wt). The physicochemical and sensory properties of the fermented ciba pepper samples were evaluated. Sensory evaluation indicated that LJC and LJD received higher scores compared to the other groups. The total acid and amino acid nitrogen contents displayed contrasting trends with the salt additions (p < 0.05). The E-nose analysis successfully differentiated the flavor profiles of the ciba pepper samples fermented with varying salt additions. Additionally, the GC-IMS analysis identified a total of 72 volatile compounds, including 14 alcohols, 21 esters, nine aldehydes, four acids, eight ketones, three terpenes, and eight other substances. Notably, the ciba pepper samples with lower salt additions exhibited higher levels of alcohols, aldehydes, and esters. In conclusion, the addition of salt during the fermentation process significantly influenced the formation of flavor compounds in ciba pepper. This study provides valuable insights into ciba pepper fermentation with different salt additions and offers prospects for the development of low-salt fermented ciba pepper products.

The objective of this study was to compare and analyze the quality of four kinds of traditional vinegar from Sichuan Province. Through chemical analysis methods such as automatic amino acid analyzer, high-phase liquid chromatography (HPLC) and solid-phase microextraction gas-phase-mass-spectrometry (SPME-GC-MS) technologies were used to determine and analyze the types and contents of amino acids, organic acids, and volatile organic compounds (VOCs). Finally, in addition to sensory analysis, intelligent sensory such as electronic nose and electronic tongue combined with principal component analysis (PCA) and cluster analysis (CA) were used for characterization. The results showed that：The pH and total acid ranges of the Sichuan vinegar samples were from 3.08 to 3.29, and 16.40% to 18.07%, respectively. The color parameter a* and b* values were tested to be significantly different (P

Using Meyerozyma guilliermondii YB4, which was isolated and screened from southern Sichuan pickles in the laboratory, as the experimental group, we investigated the changes in growth, total ester content, and volatile flavor substances of M. guilliermondii YB4 under different NaCl concentrations. The growth of M. guilliermondii YB4 was found to be inhibited by NaCl, and the degree of inhibition increased at higher NaCl concentrations. Additionally, the total ester content of the control group (CK) was significantly lower compared to the other groups (p < 0.05). The application of NaCl also resulted in distinct changes in the volatile profile of YB4, as evidenced by E-nose results. Gas chromatography-mass spectrometry (GC-MS) and gas chromatography-ion mobility spectrometry (GC-IMS) were employed to analyze the volatile compounds. A total of 148 and 86 volatiles were detected and identified using GC-MS and GC-IMS, respectively. Differential volatiles among the various NaCl concentrations in YB4 were determined by a variable importance in projection (VIP) analysis in partial least squares-discriminant analysis (PLS-DA). These differentially expressed volatiles were further confirmed by their relative odor activity value (ROAV) and odor description. Ten key contributing volatiles were identified, including ethanol, 1-pentanol, nonanal, octanal, isoamyl acetate, palmitic acid ethyl ester, acrolein, ethyl isobutanoate, prop-1-ene-3,3’-thiobis, and 2-acetylpyrazine. This study provides insights into the specificities and contributions of volatiles in YB4 under different NaCl concentrations. These findings offer valuable information for the development of aroma-producing yeast agents and the subsequent enhancement in the flavor of southern Sichuan pickles.

This study examined the flavor profiles of fermented Ciba chili, comparing samples with Sichuan pepper (HJ) to those without Sichuan pepper (CK), using three analytical techniques: E-tongue, E-nose, and gas chromatography–ion mobility spectrometry (GC-IMS). The results obtained from the E-tongue and E-nose exhibited a clear difference in taste and flavor between CK and HJ. In detail, CK mainly exhibited a sour flavor profile, whereas HJ displayed an intricate and rich flavor. The HS-GC-IMS results identified a total of 60 compounds in the samples, with terpenes, alcohols, and esters being the primary volatile flavor compounds. Additionally, Zanthoxylum was found to significantly enhance the concentration of these compounds in fermented Ciba chili. Through robust principal component analysis (rPCA), 17 distinct flavor compounds were selected. Correlation analysis revealed that most terpenes exhibited positive correlations with LY2/LG, LY2/gCT1, LY2/Gct, LY2/G, LY2/Gh, and terpenes were found in higher concentrations in HJ. This study contributes a theoretical basis and provides data support for optimizing the fermentation process and elucidating the underlying mechanism of characteristic aroma formation in Ciba chili after fermentation.

Traditional Chinese strong-aroma baijiu (CSAB) fermentation technology has been used for thousands of years. Microbial communities that are enriched in continuous and uninterrupted fermentation pits (FPs) are important for fermentation. However, changes in the metabolic functional genes in microbial communities of FPs are still under-characterized. High-throughput sequencing technology was applied to comprehensively analyze the diversity, function, and dynamics of the metabolic genes among FPs of different ages, positions, and geographical regions. Approximately 1,375,660 microbial genes derived from 259 Gb metagenomic sequences of FPs were assembled and characterized to understand the impact of FP microorganisms on the quality of CSAB and to assess their genetic potential. The core functional gene catalog of FPs, consisting of 3379 ubiquitously known gene clusters, was established using Venn analysis. The functional profile confirmed that the flavor compounds in CSAB mainly originate from the metabolism of carbohydrates and amino acids. Approximately 17 key gene clusters that determine the yield and quality of CSAB were identified. The potential mechanism was associated with the biosynthesis of host compounds in CSAB, which relies on the abundance of species, such as Lactobacillus, Clostridium, Saccharomycetales, and the abundance of functional genes, such as CoA dehydrogenase, CoA transferase, and NAD dehydrogenase. Furthermore, the detailed metabolic pathways for the production of main flavor compounds of CSAB were revealed. This study provides a theoretical reference for a deeper understanding of substance metabolism during CSAB brewing and may help guide the future exploration of novel gene resources for biotechnological applications.

This study aimed to use atomic force microscopy to compare effects of ultrasound bath, injecting calcium chloride solution and sodium chloride solution on the ultrastructure of muscle fibers and choose the preferred meat tenderizing method. The muscles fibers were tenderized and then scanned by atomic force microscopy. When meat was treated by ultrasound bath (50 W, 100 W, 250 W), CaCl2 injection (400 mM, 500 mM) and NaCl injection (100, 200, 300, 400, 500 mM), the sarcomere length was longer as compared with the control (P

[Objective] To optimize the extraction technology of lentinan from Lentinus edodes (berk.) sing by response surface method. [Methods] With the fruiting body of L. edodes as the research materials, the extraction time, extraction temperature and solid-liquid ratio were optimized during the extraction of lentinan based on single factor test. Regression equation with the extraction rate of lentinan as the target function was obtained by Design-expert software. [Results] Based regression analysis, the optimal technology was 3.8 h extraction time, 92 °C extraction temperature and 1:43 solid-liquid ratio. Under this optimal condition, the mean value of the extraction rate of lentinan was 7.865% in verification test. [Conclusions] The research result was close to the predicted value (7.893%), showing that this regression model had good fitting degree. [ABSTRACT FROM AUTHOR]