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The bacterium Lactobacillus kefiranofaciens OSU-BDGOA1 and yeast Kluyveromyces marxianus bdgo-ym6 were previously isolated from kefir grains and have shown probiotic traits in mono- and coculture. This research evaluates the effect of introducing probiotic kefir microorganisms in monoculture and in coculture alongside yogurt starter cultures on the physicochemical and rheological properties, volatile flavor compounds, survival of the microorganisms during simulated digestion, and sensory attributes of the final fermented products. The incorporation of Lactobacillus kefiranofaciens OSU-BDGOA1 in monoculture showed promising outcomes, resulting in a final product showing more solid-like characteristics and potentially improving the texture of the product. There was also a significant increase in the concentration of desirable volatile flavor compounds in the yogurt with the monoculture, particularly 2,3-butanedione, displaying a positive correlation with buttery flavor in the sensory analysis. The inclusion of L. kefiranofaciens in monoculture also promoted better sensory attributes and was significantly better than the yogurt with the coculture with the yeast showing promising results for the incorporation of this probiotic bacterium into functional fermented dairy products.
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Coffee pulp wines were produced through the mixed fermentation of Saccharomyces cerevisiae, and the flavor and sensory characteristics were comparatively evaluated. A total of 87 volatile components were identified from five coffee pulp wines, of which 68 were present in all samples, accounting for over 99% of the total concentration. The sample fermented contained significantly higher levels of volatile metabolites (56.80 mg/g). Alcohols (22 species) and esters (26 species) were the main flavor components, with the contents accounting for 56.45 ± 3.93% and 31.18 ± 4.24%, respectively, of the total. Furthermore, 14 characteristic components were identified as potential odor-active compounds, contributing to sweet and floral apple brandy flavor. Although the characteristic components are similar, the difference in the content makes the overall sensory evaluation of the samples different. The samples formed by fermentation of four strains, which obtained the highest score (86.46 ± 0.36) in sensory evaluation, were further interpreted and demonstrated through the Mantel test. The results of the component analysis were effectively distinguished by OPLS-DA and PCA, and this validation was supported by sensory evaluation. The research results provided a technical reference for the production of coffee pulp wines.
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Café , Fermentação , Paladar , Compostos Orgânicos Voláteis , Vinho , Vinho/análise , Café/química , Compostos Orgânicos Voláteis/análise , Aromatizantes/análise , Odorantes/análise , Saccharomyces cerevisiae/metabolismo , HumanosRESUMO
Shrimps are a widely cultivated species among crustaceans worldwide due to their nutritional profile and delicacy. Because of their unique flavor, shrimp-based food products are gaining consumer demand, so there is a need to understand the flavor chemistry of shrimp meat. Further, the processing and macromolecules of shrimp meat play a significant role in flavor generation and suggest a focus on their research. However, shrimp processing generates a large amount of solid and liquid waste, creating disposal problems and environmental hazards. To overcome this, utilizing these waste products, a rich source of valuable flavor compounds is necessary. This review comprehensively discusses the nutritional aspects, flavor profile, and role of macromolecules in the flavor generation of shrimp meat. Besides, recent trends in analyzing the aroma profile of shrimp and the benefits of shrimp by-products as a source of flavor compounds have been addressed. The delicious flavor of shrimp meat is due to its volatile and nonvolatile flavor compounds. Proteins play a major role in the textural and flavor adsorption properties of shrimp meat-based products. Green extraction technologies, especially ultrasonication, are recommended for valorizing shrimp by-products as a source of flavor compounds, which have enormous applications in the food and flavor industries.
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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.
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Nariz Eletrônico , Compostos Orgânicos Voláteis , Cromatografia Gasosa-Espectrometria de Massas/métodos , Cloreto de Sódio , Compostos Orgânicos Voláteis/análise , Odorantes/análise , Ésteres/análiseRESUMO
Thirty-seven lactic acid bacteria (LAB) strains were isolated from traditional dry sausages collected from Northeast China, including Latilactobacillus sakei (29 strains), Lactiplantibacillus plantarum (4 strains), Latilactobacillus curvatus (2 strains), Weissella hellenica (1 strain), and Lactococcus lactis (1 strain). Some LAB strains had tolerance to high concentrations of sodium chloride (6%), sodium nitrite (150 mg/L NaNO2), and acid (pH 4.0). They showed good growth and acidification properties and antimicrobial activity. Among them, five LAB strains that exhibited the best technological properties were selected and inoculated in the sausage model to explore their roles in flavor development. The contents of total free amino acids (FAAs) decreased ranging from 109.11 mg/g to 58.06 mg/g. A total of 46 volatile compounds were identified and the contents of volatile compounds increased in the sausage model during fermentation. Partial least squares regression analysis showed that Lb. sakei HRB10, Lb. plantarum MDJ2, W. hellenica HRB6, and Lc. lactis HRB0 promoted the generation of FAAs and volatile compounds in the sausage model. These findings demonstrated that the autochthonous LAB species are promising for the production of sausage with better flavor and fermentation performance.
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Lactobacillales , Latilactobacillus sakei , Produtos da Carne , Fermentação , Microbiologia de Alimentos , Produtos da Carne/microbiologiaRESUMO
Fermented soybean products are gaining attention in the food industry owing to their nutritive value and health benefits. In this study, we performed genomic analysis and physiological characterization of two Debaryomyces spp. yeast isolates obtained from a Korean traditional fermented soy sauce "ganjang". Both Debaryomyces hansenii ganjang isolates KD2 and C11 showed halotolerance to concentrations of up to 15% NaCl and improved growth in the presence of salt. Ploidy and whole-genome sequencing analyses indicated that the KD2 genome is haploid, whereas the C11 genome is heterozygous diploid with two distinctive subgenomes. Interestingly, phylogenetic analysis using intron sequences indicated that the C11 strain was generated via hybridization between D. hansenii and D. tyrocola ancestor strains. The D. hansenii KD2 and D. hansenii-hybrid C11 produced various volatile flavor compounds associated with butter, caramel, cheese, and fruits, and showed high bioconversion activity from ferulic acid to 4-vinylguaiacol, a characteristic flavor compound of soybean products. Both KD2 and C11 exhibited viability in the presence of bile salts and at low pH and showed immunomodulatory activity to induce high levels of the anti-inflammatory cytokine IL-10. The safety of the yeast isolates was confirmed by analyzing virulence and acute oral toxicity. Together, the D. hansenii ganjang isolates possess physiological properties beneficial for improving the flavor and nutritional value of fermented products.
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Queijo , Debaryomyces , Fabaceae , Probióticos , Saccharomycetales , Debaryomyces/genética , Genômica , Odorantes , Filogenia , República da Coreia , Saccharomyces cerevisiae , Saccharomycetales/genética , Glycine maxRESUMO
The volatile flavor profiles and sensory properties of different vegetable soybean varieties popularized and cultivated in China for 20, 10, and 2 years (TW292, X3, and SX6, respectively) were investigated. Nutrient composition analysis revealed that TW292 had a high soluble protein and soluble sugar content but low fat content. The total free amino acid content (15.43 mg/g) and umami free amino acid content (6.08 mg/g) of SX6 were significantly higher (p < 0.05) than those of the other varieties. An electronic tongue effectively differentiated between the umami and sweetness characteristics of the vegetable soybeans. Differences in sensory evaluation results were mainly reflected in texture and taste. A total of 41 volatile compounds were identified through HS-SPME-GC-MS, and the main flavor compounds were 1-octen-3-ol, hexanal, (Z)-2-heptenal, 2-octene, nonanal, (Z)-2-decenal, and 3,5-octadien-2-one. However, the volatile composition of different vegetable soybean varieties exhibited large variability in type and relative contents. Considerable differences in nutritional, organoleptic, and aroma characteristics were found among different varieties. The results of this study will provide a good basis for the assessment and application of the major vegetable soybean varieties grown in China.
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Glycine max/química , Paladar , Verduras/química , VolatilizaçãoRESUMO
BACKGROUND: Sturgeon is one of the most precious fish resources worldwide. Low temperature vacuum heating (LTVH) has been confirmed as a good way of maintaining food quality. However, there is a lack of in-depth studies assessing the impact of LTVH on lipid oxidation and flavor formation. RESULTS: The present study compared the effect of LTVH and traditional cooking on lipid oxidation and flavor of sturgeon fillets. In total, 13 fatty acids were detected, of which polyunsaturated fatty acids content was the highest (P < 0.05). LTVH prevented the formation of conjugated diene and thiobarbituric acid reactive substances (P < 0.05), as manifested by an increased signal intensity of free radicals of electron spin resonance. The characteristic peaks intensity of lipid by Raman at 970 cm-1 , 1080 cm-1 and 1655 cm-1 were reduced, whereas peaks at 1068 cm-1 and 1125 cm-1 displayed the opposite trend. Confocal fluorescence microscopy showed that the lipids particles were reduced and distributed more evenly with an increase in heating temperature. Principal component analysis of electronic nose cannot effectively separate all groups; however, gas chromatography-ion migration spectrometry showed that the volatile flavor compounds were relatively stable during LTVH. Correlation analysis of all the above lipid oxidation indices and characteristic flavor substances showed that each treatment group was located in different quadrants and demonstrated great differentiation. CONCLUSION: Overall, the results of the present study support the view that LTVH is a healthier way of cooking. © 2022 Society of Chemical Industry.
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Ácidos Graxos , Calefação , Animais , Cromatografia Gasosa-Espectrometria de Massas/métodos , Temperatura , VácuoRESUMO
BACKGROUND: This study was carried out in order to investigate the role of post-harvest methods and roasting degree on the sensory profile of Turkish coffees and to compare the results between two sensory panels: Turkey and Brazil. Bourbon variety of Arabica coffee beans processed by three different post-harvest methods (natural, pulped natural and fully washed) and roasted at three different roasting degrees (light, medium and dark). RESULTS: Ground coffee in powder size was heated with cold water and prepared in a Turkish coffee machine. Twenty assessors - ten Turkish and ten Brazilian - were selected and trained to assess 20 flavor attributes of nine Turkish coffee samples. Sensory evaluation results showed that the effects of roasting method on flavor development were perceived more dominantly than effects of post-harvest methods. For the first time, this study highlighted the sensory analysis of Turkish coffees assessed by Turkish and Brazilian assessors. CONCLUSION: Turkish coffee flavor profiles were significantly influenced by roasting method and no significant effects of post-harvest method were observed. Sensorial properties of Turkish coffee were affected by several factors, such as geographical origin and techniques used for preparation of coffee beans, cultural tradition, lifestyle, social behavior and habit. © 2021 Society of Chemical Industry.
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Coffea/química , Culinária/métodos , Sementes/química , Paladar , Brasil , Coffea/metabolismo , Café/química , Café/metabolismo , Manipulação de Alimentos/métodos , Temperatura Alta , Humanos , Sementes/metabolismo , TurquiaRESUMO
BACKGROUND: Chinese horsebean-chili-paste (CHCP) is a traditional fermented condiment in China, known as 'the soul of Sichuan cuisine'. The horsebean-to-meju phase in its preparation is important for CHCP production and contributes significantly to its taste and odor. In this study, a comprehensive flavor compound profiling analysis of the naturally brewed horsebean meju (NBHM) and the temperature-controlled brewed horsebean meju (TCBHM) was performed with two-dimensional gas chromatography time-of-flight mass spectrometry (GC × GC-TOFMS), and the analysis of physicochemical characteristics and free amino acids. Their aroma-active components and characteristic flavor compounds were evaluated. The flavor compounds responsible for differentiating NBHM and TCBHM were also determined based on the Fisher ratio and principal component analysis. RESULTS: The pH and the reducing sugar and amino-acid nitrogen content of NBHM were 5.38, 64.43, and 5.76 g kg-1 , respectively, whereas those of TCBHM were 5.13, 29.20, and 7.43 g kg-1 . A total of 356 volatiles were identified from 2571 compounds, and 257 volatile compounds were identified in NBHM compared to 322 volatiles in TCBHM. These two horsebean mejus (HMs) exhibited a similar proportion profile for 30 aroma-active compounds. Benzoic acid ethyl ester, 4-ethyl-2-methoxy-phenol and argnine were determined to be characteristic flavor components for NBHM, while 1-(2-furanyl)-ethanone, 2,6-dimethyl-pyrazine, threonine, valine and tyrosine were specific to TCBHM. CONCLUSION: Temperature-controlled brewed horsebean meju possessed better physicochemical and flavor characteristics than NBHM. The temperature-controlled brewing technique in CHCP production can be used as a promising alternative to the traditional natural brewing method. © 2020 Society of Chemical Industry.
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Manipulação de Alimentos/métodos , Vicia faba/química , China , Condimentos/análise , Fermentação , Alimentos Fermentados/análise , Aromatizantes/química , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Odorantes/análise , Sementes/química , Paladar , TemperaturaRESUMO
: Norvir® (ritonavir) is a Biopharmaceutical Classification System Class IV compound with poor solubility in water (~5 µg/mL) and limited oral bioavailability. Early stage development efforts were focused on an oral solution (OS) which provided reasonable bioavailability but exhibited taste-masking challenges and required the use of solvents with potential pediatric toxicity. Norvir® oral powder, 100 mg (NOP) was developed to replace OS. The objective of this study is to provide an overview of the development of NOP and palatability assessment strategy. Palatability of NOP was assessed using the flavor profile method: (1) As an aqueous suspension dose/response and (2) evaluation with foods. The dose/response sensory analysis indicated that NOP has strong intensity bitterness and burnt aromatics (3 on the 0â»3 flavor profile scale) at the clinical dose (100 mg/10 mL) and the recognition threshold was determined to be 0.3 mg/10 mL. To improve palatability, 100 mg/10 mL NOP aqueous suspension was evaluated with foods. Consuming foods high in fat and/or sugar content after NOP administration successfully reduced bitterness to a 1.5 intensity. In summary, NOP provides dose flexibility, enhanced stability, eliminated solvents, and maintains consistent bioavailability, with reduced bitterness and improved palatability via administration with common food products.
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Ritonavir/efeitos adversos , Paladar/efeitos dos fármacos , Administração Oral , Humanos , Ritonavir/administração & dosagem , Paladar/fisiologiaRESUMO
Bottle aging is the final stage before wines are drunk, and is considered as a maturation time when many chemical changes occur. To get a better understanding of the evolution of wines' flavor profile, the flavor compounds (phenolic and volatile compounds), dissolved oxygen (DO), and flavor characters (OAVs and chromatic parameters) of rosé and dry white wines bottled with different closures were determined after 18 months' bottle aging. The results showed the main phenolic change trends of rosé wines were decreasing while the trends of white wines were increasing, which could be the reason for their unique DO changing behaviors. Volatile compounds could be clustered into fluctuating, increasing, and decreasing groups using k-means algorithm. Most volatile compounds, especially some long-chain aliphatic acid esters (octanoates and decanoates), exhibited a lower decrease rate in rosé wines sealed with natural corks and white wines with screw caps. After 18 months of bottle aging, wines treated with natural corks and their alternatives could be distinguished into two groups based on flavor compounds via PLS-DA. As for flavor characters, the total intensity of aroma declined obviously compared with their initial counterparts. Rosé wines exhibit visual difference in color, whereas such a phenomenon was not observed in white wines.
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Aromatizantes/análise , Manipulação de Alimentos/métodos , Embalagem de Alimentos/métodos , Oxigênio/análise , Fenóis/análise , Compostos Orgânicos Voláteis/análise , Vinho/análise , Manipulação de Alimentos/instrumentação , Embalagem de Alimentos/instrumentação , Humanos , Odorantes/análise , PaladarRESUMO
Colonizing Bacillus in vanilla (Vanilla planifolia Andrews) beans is involved in glucovanillin hydrolysis and vanillin formation during conventional curing. The flavor profiles of vanilla beans under Bacillus-assisted curing were analyzed through gas chromatography-mass spectrometry, electronic nose, and quantitative sensory analysis. The flavor profiles were analytically compared among the vanilla beans under Bacillus-assisted curing, conventional curing, and non-microorganism-assisted curing. Vanilla beans added with Bacillus vanillea XY18 and Bacillus subtilis XY20 contained higher vanillin (3.58%±0.05% and 3.48%±0.10%, respectively) than vanilla beans that underwent non-microorganism-assisted curing and conventional curing (3.09%±0.14% and 3.21%±0.15%, respectively). Forty-two volatiles were identified from endogenous vanilla metabolism. Five other compounds were identified from exogenous Bacillus metabolism. Electronic nose data confirmed that vanilla flavors produced through the different curing processes were easily distinguished. Quantitative sensory analysis confirmed that Bacillus-assisted curing increased vanillin production without generating any unpleasant sensory attribute. Partial least squares regression further provided a correlation model of different measurements. Overall, we comparatively analyzed the flavor profiles of vanilla beans under Bacillus-assisted curing, indirectly demonstrated the mechanism of vanilla flavor formation by microbes.
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Benzaldeídos/análise , Aromatizantes/análise , Sementes/química , Vanilla/química , Compostos Orgânicos Voláteis/análise , Bacillus/metabolismo , Bacillus subtilis/metabolismo , Nariz Eletrônico , Tecnologia de Alimentos/métodos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Hidrólise , Olfato/fisiologiaRESUMO
Taste and odor (T/O) in drinking water often cause consumer complaints and are thus regulated in many countries. However, people in different regions may exhibit different sensitivities toward T/O. This study proposed a method to determine the regional drinking water odorant regulation goals (ORGs) based on the odor sensitivity distribution of the local population. The distribution of odor sensitivity to 2-methylisoborneol (2-MIB) by the local population in Beijing, China was revealed by using a normal distribution function/model to describe the odor complaint response to a 2-MIB episode in 2005, and a 2-MIB concentration of 12.9 ng/L and FPA (flavor profile analysis) intensity of 2.5 was found to be the critical point to cause odor complaints. Thus the Beijing ORG for 2-MIB was determined to be 12.9 ng/L. Based on the assumption that the local FPA panel can represent the local population in terms of sensitivity to odor, and that the critical FPA intensity causing odor complaints was 2.5, this study tried to determine the ORGs for seven other cities of China by performing FPA tests using an FPA panel from the corresponding city. ORG values between 12.9 and 31.6 ng/L were determined, showing that a unified ORG may not be suitable for drinking water odor regulations. This study presents a novel approach for setting drinking water odor regulations.
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Canfanos/química , Água Potável/química , Odorantes , Limite de DetecçãoRESUMO
Complete removal of the characteristic septic/swampy odor from Huangpu River source water could only be achieved under an ozone dose as high as 4.0 mg/L in an ozone-biological activated carbon (O3-BAC) process, which would lead to the production of high concentrations of carcinogenic bromate due to the high bromide content. This study investigated the possibility of simultaneous control of bromate and the septic/swampy odor by adding H2O2 prior to the O3-BAC process for the treatment of Huangpu River water. H2O2 addition could reduce the bromate concentration effectively at an H2O2/O3 (g/g) ratio of 0.5 or higher. At the same time, the septic/swampy odor removal was enhanced by the addition of H2O2, although optimization of the H2O2/O3 ratio was required for each ozone dose. At an ozone dose of 2.0 mg/L, the odor was removed completely at an H2O2/O3 ratio of 0.5. The results indicated that H2O2 application at a suitable dose could enhance the removal of the septic/swampy odor while suppressing the formation of bromate during ozonation of Huangpu River source water.
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Bromatos/química , Peróxido de Hidrogênio/química , Odorantes/prevenção & controle , Ozônio/química , Purificação da Água , Projetos Piloto , Abastecimento de ÁguaRESUMO
Paocai is a traditional Chinese fermented vegetable product popular in Asian countries. Recently, functional starters were used to control the fermentation process and improve the quality of paocai. In this study, three autochthonous lactic acid bacteria including Lactiplantibacillus plantarum LB6, Lactiplantibacillus pentosus LB3, and Weissella cibaria W51 were selected as starters and the effect of the starters on the fermentation of paocai was investigated. The results suggested that the inoculated fermentation led to a lower nitrite peak and more pronounced changes in pH and total titratable acid in the early stage of fermentation, compared with natural fermentation. Analysis of the flavor compounds indicated that the total content of volatile organic compounds of paocai through natural fermentation was significantly lower than that in inoculated fermentation. As for free amino acids, in the early stage of fermentation, the types and contents of free amino acids in the inoculated fermentation paocai were higher than those in the blank group. In the later stage of fermentation, the contents of amino acids representing umami and sweet tastes were also higher than those in the blank group. The bacterial community analysis showed that Lactobacillus and Lactococcus were the dominant bacteria in both inoculated fermentation and natural fermentation. Then, the correlations among physicochemical properties, microbial community and flavor compounds were revealed, and it was found that the dominant bacteria such as Lactococcus, Leuconostoc, Lactobacillus and Weissella displayed a considerable impact on the physical and chemical properties and flavor of paocai. In addition, the metabolic pathways involved in flavor formation and the abundance of related enzymes were elucidated. The abundance of enzymes involved in generating prephenic acid, 2-methylbutanoic acid, L-lactic acid, D-lactic acid, butanoic acid, etc., and in the pathway of producing flavor substances (His, Met, ethyl hexanoate, etc.) was up-regulated in the inoculated fermentation. Results presented in this study may provide a reference for the development of paocai starters and further guidance for the flavor improvement of Sichuan paocai.
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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.
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Lipídeos , Carne , Paladar , Compostos Orgânicos Voláteis , Animais , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Compostos Orgânicos Voláteis/análise , Suínos/metabolismo , Lipídeos/química , Lipídeos/análise , Carne/análise , Aromatizantes/química , Aromatizantes/metabolismo , Odorantes/análise , Metabolômica , MultiômicaRESUMO
Fermented soy foods can effectively improve the unpleasant odor of soybean and reduce its anti-nutritional factors while forming aromatic and bioactive compounds. However, a differential analysis of characteristic flavor and function among different fermented soy foods has yet to be conducted. In this study, a systematic comparison of different fermented soy foods was performed using E-nose, HS-SMPE-GC×GC-MS, bioactivity validation, and correlation analysis. The results showed that soy sauce and natto flavor profiles significantly differed from other products. Esters and alcohols were the main volatile substances in furu, broad bean paste, douchi, doujiang, and soy sauce, while pyrazine substances were mainly present in natto. Phenylacetaldehyde contributed to the sweet aroma of furu, while 1-octene-3-ol played a crucial role in the flavor formation of broad bean paste. 2,3-Butanediol and ethyl phenylacetate contributed fruity and honey-like aromas to douchi, doujiang, and soy sauce, respectively, while benzaldehyde played a vital role in the flavor synthesis of douchi. All six fermented soy foods demonstrated favorable antioxidative and antibacterial activities, although their efficacy varied significantly. This study lays the foundation for elucidating the mechanisms of flavor and functionality formation in fermented soy foods, which will help in the targeted development and optimization of these products.
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The traditional process of producing Zhenjiang aromatic vinegar faces challenges such as high water usage, wastewater generation, raw material losses, and limitations in mechanization and workshop conditions. This study introduces and evaluates a novel dry gelatinization process, focusing on fermentation efficiency and the vinegar flavor profile. The new process shows a 39.1% increase in alcohol conversion efficiency and a 14% higher yield than the traditional process. Vinegar produced through the dry gelatinization process has a stronger umami taste and a higher lactic acid concentration. Both processes detected 33 volatile substances, with the dry gelatinization process showing a notably higher concentration of 2-methylbutanal, which imparts a distinct fruity and chocolate aroma. These findings suggest that the dry gelatinization process outperforms the traditional process in several aspects.
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To improve the flavor profile and sensory quality of baijiu, the utilization of bioaugmented fermentation inoculated with functional microbiota normally serves as an effective method for directional regulation during the baijiu fermentation process. In this study, a systematic analysis of the succession patterns and volatile flavor compound profiles of microbial communities was carried out by high-throughput sequencing and solid-phase microextraction gas chromatography-mass spectrometry, respectively. The results demonstrated that the Saccharomyces cerevisiae YS222-related bioaugmentation clearly altered the microbial composition, particularly the assembly of bacteria, and promoted the quantity of the most volatile flavoring compounds, including alcohols, esters, and pyrazines. In addition, the correlation analysis showed that Saccharomyces and Lactobacillus in the augmented group were the main biomarkers associated with the dynamics of microbial community and greatly contributed to the brewing of sauce-flavor baijiu, which congruent with the outcomes of the enrichment analysis of integrated metabolic pathway. Thus, this work is beneficial for promoting the quality of baijiu and will serve as a useful reference for clarifying the possible mechanism of augmented fermentation on flavor development.