The possible inhibition mechanism of low salt dry-curing on volatile flavor deterioration in refrigerated grass carp (Ctenopharyngodon idella) blocks: Metabolomics and microorganisms.

Complex microbial communities have an important impact on the flavor of low salt dry-curing (LSD)-pretreated grass carp blocks. Here, the flavors, metabolites, and bacterial diversity of LSD-pretreated fish during cold storage were analyzed using flavor analysis, metabolomics, and high-throughput sequencing to investigate their correlations in detail. LSD promoted the volatile flavor deterioration of grass carp blocks under 6 days of refrigeration but inhibited it under 15 days of refrigeration. Furthermore, 924 metabolites were identified in the refrigerated grass carp blocks, and LSD inhibited the growth of Psychrophilic dominant spoilage microorganisms (Proteobacteria) and promoted microbial abundance (Actinobacteriota, Firmicutes, Bacteroidota, and Cyanobacteria). Correlation analysis revealed that the degradation of phosphatidylcholine connected with the monomonas genus in LSD-pretreated fish blocks played a vital role in inhibiting the key volatile flavor (esters, aldehydes, and alcohols) deterioration. This information is useful for elucidating the inhibition mechanism of LSD on flavor deterioration in refrigerated fish blocks.

Effect of cooking methods on flavor profiles of Xuanwei Ham: Analytical insights into aromatic composition and sensory attributes.

To examine flavor variations in Xuanwei ham due to different cooking methods, we selected one-year cured Xuanwei ham and applied four techniques: dry frying (DF), baking (BA), steaming (ST), and boiling (BO). Organoleptic evaluation revealed ST received the highest overall sensory score. High-performance liquid chromatography (HPLC) revealed that the total nucleotide content was significantly different (P < 0.05), lactic acid predominated the measured organic acids. Solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS) and chromatography-electronic nose (GC-E-Nose) data indicated that ST resulting in significantly higher total volatile compounds than the other methods (P < 0.05). SPME-GC-MS detected 55 volatile compounds, and 12 characteristic flavor substances were identified using orthogonal partial least squares discriminant analysis (OPLS-DA) (VIP > 1). This study aimed to support comprehensive research on the flavor characteristics of cooked Xuanwei ham and guide the selection of appropriate processing methods.

The dynamic changes and correlations between biochemical properties, flavor and microbial community during fermentation of asparagus by-products.

Asparagus by-products are the promising resource that urgently need to be re-valorized. This study investigated the dynamic changes in physicochemical properties, organic acids, free amino acids, volatile flavor compounds, microbial succession, and their correlations during 7-day spontaneous fermentation of asparagus by-products. Dominant organic acids (lactic acid and acetic acid) and free amino acids (Ser, Glu, and Ala) increased with fermentation time, with lactic acid reaching 7.73 ± 0.05 mg/mL and Ser increasing 56-fold after 7 days. A total of 58 volatile flavor compounds were identified using headspace solid-phase microextraction-gas chromatography-mass spectrometry (HS-SPEM/GC-MS), with esters, alcohols and acids as the main volatile flavor compounds. Fourteen volatile flavor compounds had odor activity value >1. High-throughput sequencing showed Firmicutes and Proteobacteria as the main bacterial phyla, dominated by lactic acid bacteria (Levilactobacillus, Lactiplantibacillus, Weissella). Correlation analysis revealed that five bacterial genera (Levilactobacillus, Lactiplantibacillus, Enterobacter, Pediococcus and Acetobacter) were highly correlated with organic acids, free amino acids, and volatile flavor compounds, indicating their pivotal role in forming the characteristic flavor of fermented asparagus by-products (FAPS). This study provides new insights into the flavor and microbial profile of FAPS, offering a strategy for value-added processing and industrial production.

Effect of High-Pressure Processing Treatment on the Physicochemical Properties and Volatile Flavor of Mercenaria mercenaria Meat.

High-pressure processing (HPP) technology can significantly improve the texture and flavor of Mercenaria mercenaria. This study aimed to investigate the effect of HPP treatment with varying levels of pressure (100, 200, 300, 400, 500, and 600 MPa) and a holding time of 8 min at 20 °C on the physicochemical properties and volatile flavors of M. mercenaria. The significant changes in hardness, resilience, and water holding capacity occurred with increasing pressure (p < 0.05), resulting in improved meat quality. Scanning electron microscopy (SEM) was utilized to observe the decomposition of muscle fibers in M. mercenaria due to varying pressures, which explains the differences in texture of M. mercenaria. Different pressure treatments also had an influence on the volatile flavor of M. mercenaria, and the quantities of low-molecular-weight aldehydes (hexanal, heptanal, and nonanal) with a fishy taste decreased dramatically following 400 and 500 MPa HPP treatments. Furthermore, the level of 2-Methylbutyraldehyde, which is related to sweetness, increased significantly following 400 MPa HPP treatment. The study found that 400 MPa HPP treatment resulted in minor nutrient losses and enhanced sensory quality. The results of this study provide a theoretical basis for the application of HPP treatment to M. mercenaria.

Insights into the molecular mechanisms of lipid metabolism of air-dried goose on the formation of flavor substances by co-inoculation of lactic acid bacteria and staphylococcus based on GC-MS and lipidomics.

Microorganisms and lipids always interact in a complex way in the meat matrix, which affects the flavor of meat products. This study aimed to examine the impact of complex fermentation with distinct microorganisms on fat oxidation, lipid profile, and the biochemical pathways involved in flavor substance formation. GC-MS analysis revealed that 12 key volatile substances including hexanal, heptanal, benzeneacetaldehyde, decanal, 1-nonanol, 1-hexanol, 1-octen-3-ol were responsible for the flavor variations in geese. Lipidomics analysis of three groups identified 440 lipid molecules, with triglycerides and glycerophospholipids being the most abundant categories. Spearman correlation analysis showed that 4 key volatile substances exhibited positive correlations with lysophosphatidylethanolamines, lysophosphatidycholines, phosphatidylcholines, phosphatidylethanolamines. The data presented herein facilitate an understanding of the lipid dynamics during fermentation and provide insights into the potential for controlling the flavor quality of fermented air-dried meat products.

Roles of cigar microbes in flavor formation during roasted-rice leachate fermentation.

Roasted-rice leachate fermentation, a distinctive local tobacco fermentation method in Sichuan, imparts a mellow flavor and glossy texture to tobacco leaves, along with a roasted rice aroma. In order to find out the impact of roasted-rice leachate on cigar tobacco leaves, the physicochemical properties, volatile flavor profile, and microbial community were investigated. The content of protein significantly decreased after fermentation. The volatile flavor compounds increased following roasted-rice leachate fermentation, including aldehydes, alcohols, acids, and esters. High-throughput sequencing identified Staphylococcus, Pseudomonas, Pantoea, Oceanobacillus, Delftia, Corynebacterium, Sphingomonas, Aspergillus, Weissella, and Debaryomyces as the primary genera. Network and correlation analysis showed Debaryomyces played a crucial role in roasted-rice leachate fermentation, due to its numerous connections with other microbes and positive relationships with linoelaidic acid, aromandendrene, and benzaldehyde. This study is useful for gaining insight into the relationship between flavor compounds and microorganisms and provides references regarding the effect of extra nutrients on traditional fermentation products. KEY POINTS: • Volatile flavor compounds increased following roasted-rice leachate fermentation • Staphylococcus was the primary genera in fermented cigar • Debaryomyces may improve the quality of tobacco leaves.

Effects of Different Roasting Methods on the Quality of Roasted Large Yellow Croaker (Larimichthys crocea).

This study investigated the effects of different roasting methods (45% light wave and 55% microwave roasting, 70% light wave and 30% microwave roasting, 100% light wave roasting, far-infrared roasting, and oven roasting) on the quality of roasted large yellow croaker. The quality was evaluated using sensory evaluation, texture characteristics, color differences, moisture content, and volatile flavor substances. In this context, different roasting methods can affect the color, taste, and flavor of large yellow croaker fish, significantly improving the overall acceptance of roasted fish. The results showed that after 45% light wave and 55% microwave roasting, the elasticity of fish meat was maintained, the hardness of fish meat was reduced, the moisture content and distribution were changed, and the taste was the best. Far-infrared roasting and 45% light wave and 55% microwave roasting had a significant effect on the color of large yellow croaker samples and improved the sensory evaluation score. Forty-six volatile compounds were detected using gas chromatography-mass spectrometry. After roasting, the oxidation and Maillard reactions of lipids and proteins were increased, with the 45% light wave and 55% microwave roasting giving the highest variety of volatile flavor substance products.

Effects of Pre-Dehydration Treatments on Physicochemical Properties, Non-Volatile Flavor Characteristics, and Microbial Communities during Paocai Fermentation.

The paocai industry faces challenges related to the production of large volumes of high-salinity and acidic brine by-products. Maintaining paocai quality while reducing brine production is crucial. This study utilized high-throughput sequencing technology to analyze microbial changes throughout the fermentation process, along with the non-volatile flavor compounds and physicochemical properties, to assess the impact of hot-air and salt-pressing pre-dehydration treatments on paocai quality. The findings indicate that pre-dehydration of raw material slowed the fermentation process but enhanced the concentration of non-volatile flavor substances, including free amino acids and organic acids. Hot-air pre-dehydration effectively reduced initial salinity to levels comparable to those in high-salinity fermentation of fresh vegetables. Furthermore, pre-dehydration altered microbial community structures and simplified inter-microbial relationships during fermentation. However, the key microorganisms such as Lactobacillus, Weissella, Enterobacter, Wallemia, Aspergillus, and Kazachstania remained consistent across all groups. Additionally, this study found that biomarkers influenced non-volatile flavor formation differently depending on the treatment, but these substances had minimal impact on the biomarkers and showed no clear correlation with high-abundance microorganisms. Overall, fermenting pre-dehydrated raw materials presents an environmentally friendly alternative to traditional paocai production.

Study of volatile flavor derived from lipids degeneration in yak Milk based on Semiquantitative Lipidomics.

Milk lipids greatly affect the volatile flavor of milk, and the relationship between lipids and volatile flavor in yak milk was explored in this study. The volatile flavor compounds (VFCs), lipids profile, fatty acids in yak ordinary milk and colostrum were detected with HP/SPME-GC-MS, the semiquantitative lipidomics based on LC-MS/MS, GC-MS, respectively. The VFCs differences in yak milk were closely related to 1-((1 s,3ar,4r,7 s,7as)-4-hydroxy-7-isopropyl-4-methyloctahloctahydro-1h-inden-1-Yl)-ethanone,2,6,6-trimethyl-2,4-cycloheptadien-1-one, pentanal, 2-phenylethyl propionate, octanoic acid methyl ester, diphosphoric acid diisooctyl ester, (Z)-3,4,4-trimethyl-5-oxo-2-hexenoic acid and acetic acid. The volatile flavor in yak milk was well correlated with milk lipids, and TG(4:0_12:3_18:1), TG(6:0_8:0_18:1), TG(4:0_12:3_18:1), TG(12:0_18:2_18:3) and TG(16:0e_18:1_22:5) were the crucial lipid molecules affecting volatile flavor. The degeneration of above lipids by hydrolysis produced some fatty acids and alcohol, then these compounds were further derived into other VFCs especially above crucial 8 molecules. This study provided a theoretical basis for improving the volatile flavor by controlling lipids in yak milk.

The Potential Correlation between Bacterial Diversity and the Characteristic Volatile Flavor Compounds of Sichuan Sauce-Flavored Sausage.

The distinctive taste of Sichuan sauce-flavored sausage comes from an intricate microbial metabolism. The correlation between microbial composition and distinct flavor components has not been researched. The study used headspace solid-phase microextraction action with gas chromatography mass spectrometry to find flavor components and high-throughput sequencing of 16S rRNA to look at the diversity and succession of microbial communities. The correlation network model forecasted the connection between essential bacteria and the development of flavors. The study revealed that the primary flavor compounds in Sichuan sauce-flavored sausages were alcohols, aldehydes, and esters. The closely related microbes were Leuconostoc, Pseudomonas, Psychrobacter, Flavobacterium, and Algoriella. The microbes aided in the production of various flavor compounds, such as 1-octen-3-ol, benzeneacetaldehyde, hexanal, (R,R)-2,3-butanediol, and ethyl caprylate. This work has enhanced our comprehension of the diverse functions that bacteria serve in flavor development during the fermentation of Sichuan sauce-flavored sausage.

A Comparative Study of Microbial Communities, Biogenic Amines, and Volatile Profiles in the Brewing Process of Rice Wines with Hongqu and Xiaoqu as Fermentation Starters.

Rice wine is primarily crafted from grains through saccharification and liquification with the help of Qu. Qu plays an important role in the formation of the flavor quality of rice wine. Hongqu and Xiaoqu represent two prevalent varieties of Qu that are typically utilized in the brewing process of rice wine and play a crucial role in its production. In this study, GC, GC-MS, HPLC, and metagenomic sequencing techniques were used to contrast the microbial flora, biogenic amines, and aroma characteristics developed during the fermentation of rice wines, with Hongqu and Xiaoqu being used as initiating agents for the brewing process. The results show that the content of higher alcohols (including n-propanol, isobutanol, 3-methyl-1-butanol, and phenethyl alcohol) in rice wine brewed with Xiaoqu (XQW) was significantly higher than that in rice wine brewed with Hongqu (HQW). Contrarily, the concentration of biogenic amines in HQW surpassed that of XQW by a notable margin, but tyramine was significantly enriched in XQW and not detected in HQW. In addition, a multivariate statistical analysis revealed distinct disparities in the constitution of volatile components between HQW and XQW. Hexanoic acid, ethyl acetate, isoamyl acetate, ethyl caproate, ethyl decanoate, 2-methoxy-4-vinylphenol, etc., were identified as the characteristic aroma-active compounds in HQW and XQW. A microbiome analysis based on metagenomic sequencing showed that HQW and XQW had different dominant microorganisms in the brewing process. Burkholderia, Klebsiella, Leuconostoc, Monascus, and Aspergillus were identified as the primary microbial genera in the HQW fermentation period, while Pediococcus, Enterobacter, Rhizopus, Ascoidea, and Wickerhamomyces were the main microbial genera in the XQW brewing process. A bioinformatics analysis revealed that the concentrations of microbial genes involved in biogenic amines and esters biosynthesis were significantly higher in HQW than those in XQW, while the content of genes relevant to glycolysis, higher alcohol biosynthesis, and fatty acid metabolism was significantly higher in XQW than in HQW, which are the possible reasons for the difference in flavor quality between the two kinds of rice wine from the perspective of microbial functional genes.

Effects of Wickerhamomyces anomalus Co-Fermented with Saccharomyces cerevisiae on Volatile Flavor Profiles during Steamed Bread Making Using Electronic Nose and HS-SPME-GC-MS.

Steamed bread is a traditional staple food in China, and it has gradually become loved by people all over the world because of its healthy production methods. With the improvement in people's living standards, the light flavor of steamed bread fermented by single yeast cannot meet people's needs. Multi-strain co-fermentation is a feasible way to improve the flavor of steamed bread. Here, the dynamic change profiles of volatile substances in steamed bread co-fermented by Saccharomyces cerevisiae SQJ20 and Wickerhamomyces anomalus GZJ2 were analyzed using the electronic nose (E-nose) and headspace solid-phase microextraction combined with gas chromatography-mass spectrometry (HS-SPME-GC-MS). The five detectors of the E-nose rapidly detected the changes in volatile substances in different dough or steamed bread with the highest response value in co-fermented dough. A total of 236 volatile substances were detected in all the samples using HS-SPME-GC-MS, and alcohols were the most variable component, especially Phenylethyl alcohol. Significantly, more alcohols and esters were upregulated in co-fermented dough, and the addition of W. anomalus GZJ2 improved the key volatile aroma compounds of steamed bread using the relative odor activity value method (ROAV), especially the aldehydes and alcohols. Moreover, these key volatile aroma compounds can be quickly distinguished using the W2S detector of the E-nose, which can be used for the rapid detection of aroma components in steamed bread.

Study on the Changes and Correlation of Microorganisms and Flavor in Different Processing Stages of Mianning Ham.

(1) Background: Mianning ham is a dry-cured ham from Southwest China, known for its distinct regional characteristics and delicious taste. It is particularly favored by consumers due to its safety, as no artificial nitrites are added during processing. The microbial changes during its different processing stages significantly influence the final product's flavor. This study aims to investigate the changes in microbial communities and flavor compounds across the nine stages of Mianning ham production, from raw material preparation to salting, drying, fermentation, and maturation, using 16S and ITS sequencing, as well as solid-phase microextraction-gas chromatography-mass spectrometry (SPME-GC-MS). The goal is to explore the correlation between these changes and provide a basis for process improvement from the initial raw material preparation. (2) Results: The microbiota of Mianning ham across different processing stages mainly consisted of Proteobacteria, Firmicutes, and Ascomycota. A total of 324 volatile compounds were identified, of which 27 were key contributors to the ham's flavor. Aldehydes contributed the most to flavor, with octanal, trans-2-nonenal, and trans, trans-2,4-decadienal being the most significant contributors at various stages. Mature Mianning ham, fermented for 1-3 years, exhibited fresh grass and earthy aromas, buttery and fatty flavors, and a distinctive roasted potato note. Correlation analysis revealed that Cobetia was the primary bacterial contributor to the main flavor compounds, especially prominent in the second year of fermentation. Among fungi, Yamadazyma and Aspergillus positively influenced several key aldehyde flavor compounds throughout the processing stages, significantly contributing to the flavor profile of Mianning ham. (3) Conclusions: Correlation analysis showed that the Mianning ham that matured for two years had the richest and most characteristic flavor. The positive and consistent impact of fungi on the ham's flavor suggests that they may warrant further research and application in Mianning ham production. This provides a theoretical basis for improving the flavor quality and enhancing the market competitiveness of Mianning ham. One of the key features of Mianning ham is its substantial accumulation of hydrocarbons, which surpasses that of hams from other regions in China. A notable characteristic of Mianning ham processing is the absence of artificially added nitrites as antioxidants and color fixatives. Whether this absence is a contributing factor to the significant accumulation of hydrocarbons warrants further investigation.

Comparative Analysis of Commercially Available Flavor Oil Sausages and Smoked Sausages.

This study utilized gas chromatography-ion mobility spectrometry (GC-IMS) to analyze the volatile flavor compounds present in various commercially available sausages. Additionally, it conducted a comparative assessment of the distinctions among different samples by integrating sensory evaluation with textural and physicochemical parameters. The results of the GC-IMS analysis showed that a total of 65 volatile compounds were detected in the four samples, including 12 hydrocarbons, 11 alcohols, 10 ketones, 9 aldehydes, 12 esters, and 1 acids. Fingerprinting combined with principal component analysis (PCA) showed that the volatiles of different brands of sausages were significantly different (p < 0.05). The volatiles of S1 and S4 were more similar and significantly different from the other two samples (p < 0.05). Among them, there were 14 key volatile substances in the four samples, of which 3-hydroxy-2-butanone and diallyl sulfide were common to all four sausages. Combined textural and sensory evaluations revealed that smoked sausages exhibited superior characteristics in resilience, cohesiveness, springiness, gumminess, and chewiness. Additionally, smoked sausages were found to be more attractive in color, moderately spicy, and salty, while having a lower fat content. In conclusion, smoked sausages are preferred by consumers over flavored oil sausages.

Analysis of flavor substances changes during fermentation of Chinese spicy cabbage based on GC-IMS and PCA.

This study employed a combination of principal component analysis (PCA) and gas chromatography-ion mobility spectrometry (GC-IMS) to examine the distinctive taste mixtures produced by Chinese spicy cabbage (CSC) fermented at varying temperatures. As the fermentation progressed, the pH gradually decreased and stabilized after the 11 days of fermentation, and the total content of organic acids and short-chain fatty acids increased. A total of 49 volatile mixtures were detected during CSC fermentation and storage for 21 days. These included 7 aldehydes, 6 alcohols, 7 esters, 6 ketones, 5 pyrazines, 4 sulfides, 4 phenols, 2 ethers, 2 olefins, and 1 acid. With time, the content of most volatile flavor substances decreased. PCA of the signal intensities of the volatile chemicals in the samples showed significant differences in the flavor of CSC fermented at different temperatures; consequently, the samples fermented at different temperatures were effectively separated in relatively independent regions of CSC. Therefore, low-temperature fermentation and storage at 4 °C were more suitable for CSC. Based on the identified volatile chemicals, HS-GC-IMS and PCA could effectively construct the flavour fingerprints of CSC samples. This study provided a theoretical basis for improving the fermentation quality of CSC.

Effects of the photovoltaic fishery culture model on muscle nutritional quality and volatile flavor compounds of Litopenaeus vannamei.

This study used Litopenaeus vannamei to compare the muscle nutritional quality and volatile flavor compounds of animals raised in the photovoltaic fishery culture model (PM) and the common pond breeding model (CM). Amino acids, fatty acids, and volatile flavor substances were identified and analyzed using an automatic amino acid analyzer and headspace solid phase microextraction(HS-SPME) combined with GC/MS. There were no significant differences between the two culture models in terms of general nutrients, mineral contents, and amino acid compositions in the muscles of L. vannamei. In the PM group, the proportion of flavor amino acids in total amino acids was higher. Based on the amino acid score (AAS) and chemical score (CS), it was found that methionine and cystine were the first limiting amino acids in the muscle samples. The essential amino acid index (EAAI) value was approximately 77 for both models, indicating high-quality proteins. The muscles contained nine types of fatty acids, with the PM group showing significantly higher levels of both monounsaturated and total fatty acids. A total of 23 volatile flavor compounds were identified in both models. The contents of 1-nonanal, n-tridecane, and alpha-terpineol were higher when cultured in the PM. Conversely, the contents of hexanal, 2-ethylhexanol, and dipentene were lower in the PM group. The photovoltaic fishery culture model has the potential to enhance income through photovoltaic power generation. In addition, this study found that the fatty acid composition of L. vannamei was improved in the PM, without compromising muscle composition or flavor. These results provide a theoretical basis for evaluating the meat quality of L. vannamei under different culture models and offer data to support and guide the promotion of the PM.

Revealing the mechanism of flavor improvement of fermented goat milk based on lipid changes.

The mechanism of goat milk (GM) flavor improvement based on lipid changes requires understanding. According to sensory evaluation results, the texture, taste, appearance, aroma, and overall acceptability score of Guishan fermented goat milk (GMF) were higher than those of GM. In total, 779 lipid molecules and 121 volatile compounds were formed from the metabolite-lipid level in the GM and GMF, as determined through lipidomics and gas chromatography-mass spectrometry. The key volatile flavor compounds in the GMF were (E,E)-2,4-decadienal, ethyl acetate, acetoin, 2,3-pentanedione, acetic acid, and 2,3-butanedione. Of them, 60 lipids significantly contributed to the flavor profiles of the GMF, based on the correlation analysis. The triacylglycerides (TAGs) 12:0_14:0_16:0 and 13:0_13:0_18:2 contributed to aroma retention, while TAG and phosphatidylethanolamine were identified as key substrates for flavor compound formation during fermentation. Lipids associated with glycerophospholipid and linoleic acid metabolism pathways significantly affected volatile compound formation in the GMF. This study provides an in-depth understanding of the lipids and flavors of the GMF, and this information will be useful for the development of specific GMF products.

Ultrasound-induced modifications of beef flavor characteristics during postmortem aging.

To investigate the effect of ultrasound treatment on the flavor profile of beef during postmortem aging, a comprehensive analysis of beef flavor was conducted at 0, 7, and 12 d of aging using sensory evaluation and electronic nose. Furthermore, the key volatile flavor compounds were identified using gas chromatography-mass spectrometry (GC-MS), and the odor activity value (OAV) was further evaluated. In addition, the primary pathway involved in flavor formation during beef aging after ultrasound treatment was explored. The results indicated that ultrasound enhanced the flavor profile of beef during postmortem aging by modifying the OAV of hexanal, heptanal, octanal, nonanal, decanal, (Z)-2-nonenal, dodecanal, pentanal, 1-octen-3-ol, octanoic acid, and 2-pentylfuran. Lipid oxidation was a crucial pathway through which ultrasound promoted the generation of volatile flavor compounds in beef, confirmed by the improved oxidation level of fatty acids, particularly monounsaturated ones. The study indicates that ultrasound technology can be regarded as an effective method for enhancing the beef flavor profile during postmortem aging.

Comprehensive characterization of the differences in metabolites, lipids, and volatile flavor compounds between Ningxiang and Berkshire pigs using multi-omics techniques.

This study was conducted to comprehensively characterize, metabolites, lipids, and volatile flavor compounds of NingXiang (NX) pigs, Berkshire (BKS) pigs, and their crossbred (Berkshire × Ningxiang, BN) pigs using multi-omics technique. The results showed that NX had high intramuscular fat (IMF) content and meat redness. The metabolite and lipid compositions were varied greatly among three pig breeds. The NX pigs exhibited distinctive sweet, fruity, and floral aroma while BN pigs have inherited this flavor profile. 2-pentylfuran, pentanal, 2-(E)-octenal, and acetic acid were the key volatile flavor compounds (VOC) of NX and BKS pork. The VOCs were influenced by the composition and content of metabolites and lipids. The NX pigs have excellent meat quality traits, unique flavor profiles, and high degree of genetic stability regarding flavor. The study deepens our understanding of the flavor of Chinese indigenous pigs, providing theoretical basis to understand the meat flavor regulation under different feeding conditions.

Comparative Analysis of Texture Characteristics, Sensory Properties, and Volatile Components in Four Types of Marinated Tofu.

In this study, three different brands of commercially available marinated tofu were analyzed and compared with homemade products to explore the effect of key flavor substances on their sensory quality, sensory properties, texture characteristics, and volatile components. The texture characteristics and flavor substances of the three brands of commercially available marinated tofu were significantly different from those of homemade products. A total of 64 volatile components were identified by headspace-gas chromatography-ion mobility spectrometry (HS-GC-IMS), mainly including 11 hydrocarbons, 11 alcohols, 10 ketones, 15 aldehydes, 4 esters, 1 acid, and 12 other volatile substances. Among these, nine key flavor compounds (ROAV > 1, VIP > 1) were identified using the relative odor activity value (ROAV) combined with a partial least squares discriminant analysis (PLS-DA) and variable importance in projection, including α-Pinene, ß-Myrcene, α-Phellandrene, 1-Penten-3-one, Butanal, 3-Methyl butanal, acetic acid ethyl ester, 1,8-Cineol, and 2-Pentyl furan. The correlation heatmap showed that sensory evaluation was positively correlated with hardness, gumminess, chewiness, and springiness while negatively correlated with 2-Pentyl furan, α-Pinene, resilience, α-Phellandrene, 1-Penten-3-one, acetic acid ethyl ester, and 1,8-Cineol. Overall, this study provides a theoretical reference for developing new instant marinated tofu snacks.