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1.
J Sci Food Agric ; 102(1): 73-84, 2022 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-34029397

RESUMO

BACKGROUND: Mushroom possesses desirable aroma, taste, texture, health-promoting and disease-preventing dietary components, making it an ideal ingredient, especially for animal-based food substitution. Nevertheless, no study has replaced egg whites partially with mushrooms and investigated their sensory quality. This study aimed to investigate flavor impartment of mushroom on egg whites and the sensory quality of roasting and steaming egg whites replaced by white and crimini mushrooms at 0%, 10%, 20% and 30%, respectively, using a panel trained with aroma chemical references for 31 sensory attributes with 0-10 line scales. RESULTS: Roasted and steamed egg whites possessed major sensory attributes of sulfury and egg-like aroma and flavor (intensities > 3). After mushroom topping was added, the dominant sensory attributes shifted to mushroom-based flavor characteristics, including mushroom-like, earthy, dark meat, roasted, hay, soybean, potato, woody, umami, bitter, astringent and firmness texture. Mushroom variety showed significant (P ≤ 0.05) impacts on egg white sensory quality, with crimini introducing more intense flavor. The higher the mushroom proportion with egg whites, the more intense was the flavor associated with mushroom. Mushroom could enhance egg-like flavor in multiple dimensions, including aroma, taste and texture, according to partial least square regression. CONCLUSION: White and crimini mushrooms enriched roasted and steamed egg white sensory quality with introduction of characteristic sensory attributes from mushrooms. Mushroom variety and proportion with egg whites displayed significant impacts on egg white sensory properties. The study contributed to understanding the impact of mushrooms on egg white sensory profile and served as a guide in incorporating mushroom in product development. © 2021 Society of Chemical Industry.


Assuntos
Agaricales/química , Clara de Ovo/química , Paladar , Agaricales/metabolismo , Animais , Galinhas , Culinária , Aromatizantes/química , Aromatizantes/metabolismo , Humanos , Odorantes/análise , Olfato
2.
Braz J Biol ; 83: e250550, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34730714

RESUMO

Vanillin is the major component which is responsible for flavor and aroma of vanilla extract and is produced by 3 ways: natural extraction from vanilla plant, chemical synthesis and from microbial transformation. Current research was aimed to study bacterial production of vanillin from native natural sources including sewage and soil from industrial areas. The main objective was vanillin bio-production by isolating bacteria from these native sources. Also to adapt methodologies to improve vanillin production by optimized fermentation media and growth conditions. 47 soil and 13 sewage samples were collected from different industrial regions of Lahore, Gujranwala, Faisalabad and Kasur. 67.7% bacterial isolates produced vanillin and 32.3% were non-producers. From these 279 producers, 4 bacterial isolates selected as significant producers were; A3, A4, A7 and A10. These isolates were identified by ribotyping as A3 Pseudomonas fluorescence (KF408302), A4 Enterococcus faecium (KT356807), A7 Alcaligenes faecalis (MW422815) and A10 Bacillus subtilis (KT962919). Vanillin producers were further tested for improved production of vanillin and were grown in different fermentation media under optimized growth conditions for enhanced production of vanillin. The fermentation media (FM) were; clove oil based, rice bran waste (residues oil) based, wheat bran based and modified isoeugenol based. In FM5, FM21, FM22, FM23, FM24, FM30, FM31, FM32, FM34, FM35, FM36, and FM37, the selected 4 bacterial strains produced significant amounts of vanillin. A10 B. subtilis produced maximum amount of vanillin. This strain produced 17.3 g/L vanillin in FM36. Cost of this fermentation medium 36 was 131.5 rupees/L. This fermentation medium was modified isoeugenol based medium with 1% of isoeugenol and 2.5 g/L soybean meal. ech gene was amplified in A3 P. fluorescence using ech specific primers. As vanillin use as flavor has increased tremendously, the bioproduction of vanillin must be focused.


Assuntos
Benzaldeídos , Aromatizantes , Alcaligenes faecalis/metabolismo , Bacillus subtilis/metabolismo , Benzaldeídos/metabolismo , Meios de Cultura , Enterococcus faecium/metabolismo , Fermentação , Aromatizantes/metabolismo , Microbiologia Industrial , Pseudomonas fluorescens/metabolismo
3.
Molecules ; 26(20)2021 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-34684821

RESUMO

Currently, there is a growing demand for flavorings, especially of natural origin. It is worth paying attention to the biotechnological processes of flavor production, characterized by simplicity, high efficiency and relatively low cost. In this study, we analyzed the ability of the Galac tomyces geotrichum mold to transform by-products of the dairy industry: sour whey and buttermilk to complex flavour mixtures with pleasant, honey-rose aroma. Furthermore, the aroma complexity of the fermentation product has been carefully identified applying a sensomic approach involving the use of gas chromatography-olfactometry (GC-O), gas chromatography-mass spectrometry (GC-MS) and stable isotope dilution assay (SIDA) to identify and quantify aroma compounds. Based on the calculation of odor activity value (OAV), 13 key aroma compounds were present in both tested variants. The highest OAVs were found for phenylacetaldehyde (honey-like) in the buttermilk variant (912) and 2-phenylethanol (rose-like) in the sour whey variant (524). High values of this indicator were also recorded for phenylacetaldehyde (319) and 3-methyl-1-butanol with a fruity aroma (149) in the sour whey culture. The other compounds identified are 3-methylbutanal (malty), 2,3-butanedione (cheesy), isovaleric acid (cheesy), 3-(methylthio)-propanal (boiled potato), butanoic acid (vinegar), (E)-2-nonenal (fatty), ethyl furaneol (burnt sugar), dimethyl trisulfide (cabbage), and acetic acid (vinegar).


Assuntos
Leitelho/análise , Leitelho/microbiologia , Microbiologia de Alimentos , Geotrichum/metabolismo , Odorantes/análise , Soro do Leite/química , Soro do Leite/microbiologia , Acetaldeído/análogos & derivados , Acetaldeído/análise , Biotecnologia , Biotransformação , Fermentação , Aromatizantes/metabolismo , Tecnologia de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Olfatometria , Álcool Feniletílico/análise , Paladar , Compostos Orgânicos Voláteis/análise
4.
Molecules ; 26(15)2021 Jul 28.
Artigo em Inglês | MEDLINE | ID: mdl-34361722

RESUMO

Off-flavors produced by undesirable microbial spoilage are a major concern in wineries, as they affect wine quality. This situation is worse in warm areas affected by global warming because of the resulting higher pHs in wines. Natural biotechnologies can aid in effectively controlling these processes, while reducing the use of chemical preservatives such as SO2. Bioacidification reduces the development of spoilage yeasts and bacteria, but also increases the amount of molecular SO2, which allows for lower total levels. The use of non-Saccharomyces yeasts, such as Lachancea thermotolerans, results in effective acidification through the production of lactic acid from sugars. Furthermore, high lactic acid contents (>4 g/L) inhibit lactic acid bacteria and have some effect on Brettanomyces. Additionally, the use of yeasts with hydroxycinnamate decarboxylase (HCDC) activity can be useful to promote the fermentative formation of stable vinylphenolic pyranoanthocyanins, reducing the amount of ethylphenol precursors. This biotechnology increases the amount of stable pigments and simultaneously prevents the formation of high contents of ethylphenols, even when the wine is contaminated by Brettanomyces.


Assuntos
Brettanomyces/metabolismo , Aromatizantes/metabolismo , Tecnologia de Alimentos/métodos , Odorantes/análise , Saccharomycetales/metabolismo , Vinho/análise , Antocianinas/metabolismo , Carboxiliases/metabolismo , Fermentação , Proteínas Fúngicas/metabolismo , Humanos , Concentração de Íons de Hidrogênio , Ácido Láctico/metabolismo , Dióxido de Enxofre/farmacologia , Vitis/metabolismo , Vitis/microbiologia , Vinho/microbiologia
5.
Food Microbiol ; 100: 103838, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34416971

RESUMO

Hybridisation is an important evolutionary mechanism to bring about novel phenotypes and may produce new hybrids with advantageous combinations of traits of industrial importance. Within the Saccharomyces genus, Saccharomyces jurei is a newly discovered species and its biotechnological potential has not yet been fully explored. This yeast was found to be able to grow well in unhopped wort and at low temperatures, qualities necessary in good candidates for fermented bevarages. Here, we analysed its fermentation and aroma profile and created novel non-GMO hybrids between S. jurei and S. cerevisiae ale yeasts to develop new starter strains with interesting flavours for the craft brewing and beverage industry in general. Pilot beer fermentations with specific hybrids showed a good fermentation performance, similar to the ale parent strain, while eliminating the hyper-attenuation characteristic and a more complex flavour profile. This study exploits the genetic diversity of yeasts and shows how inter-specific hybridisation and clone selection can be effectively used in brewing to create new products and to eliminate or increase specific traits.


Assuntos
Cerveja/análise , Saccharomyces/genética , Saccharomyces/metabolismo , Cerveja/microbiologia , Fermentação , Aromatizantes/análise , Aromatizantes/metabolismo , Microbiologia de Alimentos , Humanos , Hibridização Genética , Odorantes/análise , Saccharomyces/crescimento & desenvolvimento , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Saccharomyces cerevisiae/metabolismo , Paladar
6.
Food Chem ; 361: 130133, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34082390

RESUMO

The study aimed to improve the quality of dry-processed coffee grown at low altitudes through yeast inoculation, using three species (Saccharomyces cerevisiae CCMA 0543, Torulaspora delbrueckii CCMA 0684, and Candida parapsilosis CCMA 0544) singly and with co-inoculation for fermentation. Important chemical compounds and groups were analyzed by liquid and gas chromatography and Fourier-transform infrared spectroscopy (FTIR). The inoculated coffees with yeast populations around 106 cell/g obtained the highest scores, and the co-inoculation with C. parapsilosis CCMA 0544 and T. delbrueckii CCMA 0684 had the highest score in the sensory analysis (85). Different descriptors were observed in each treatment, and body, flavor, balance, and aftertaste are strongly related to C. parapsilosis CCMA 0544. The fermentation process improved the quality of low-altitude coffees, and the combination of non-Saccharomyces yeasts (C. parapsilosis CCMA 0544 and T. delbrueckii CCMA 0684) was the most indicated as starter cultures.


Assuntos
Candida parapsilosis/metabolismo , Coffea/metabolismo , Café/metabolismo , Saccharomyces cerevisiae/metabolismo , Torulaspora/metabolismo , Altitude , Candida parapsilosis/química , Coffea/química , Café/química , Fermentação , Aromatizantes/química , Aromatizantes/metabolismo , Paladar
7.
Int J Food Microbiol ; 351: 109262, 2021 Aug 02.
Artigo em Inglês | MEDLINE | ID: mdl-34090033

RESUMO

Chinese horse bean-chili-paste (CHCP), a fermented condiment in China, is traditionally manufactured through naturally spontaneous semi-solid fermentation procedures without intentionally inoculated microorganisms. The aim of this study was to investigate the effect on microbiota and quality variations during CHCP fermentation by inoculation of selected autochthonous microorganisms Bacillus amyloliquefaciens and Candida versatilis. The results showed that relative abundance of Bacillus in the samples inoculated with B. amyloliquefaciens were increased from about 0.6% to almost 25%, and the batches bio-augmented with C. versatilis exhibited clearly 0.7 Lg copies/g higher biomass than that of the other samples. By bio-augmentation, six enzyme activities, namely acid protease, leucine aminopeptidase, α-amylase, cellulose, ß-glucosidase and esterase, were considerably enhanced. As a result, inoculation of these two strains exhibited significant effect on the volatile profiles of CHCP. B. amyloliquefaciens herein was found to contribute mainly to the accumulation of acids, sulfur-containing compounds and pyrazines, whereas C. versatilis was considerably associated with the formation of alcohols, esters and phenols. This study proved that combination of B. amyloliquefaciens and C. versatilis could obtain more extensive aroma profiles, especially for the enrichment of miso-like and fruity flavors, which could provide a guideline for the tailored control of CHCP fermentation process.


Assuntos
Bacillus amyloliquefaciens/metabolismo , Aromatizantes/metabolismo , Microbiota , Saccharomycetales/metabolismo , Vicia faba/microbiologia , China , Condimentos/análise , Condimentos/microbiologia , Fermentação , Aromatizantes/análise , Odorantes/análise , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo
8.
Appl Environ Microbiol ; 87(17): e0088521, 2021 08 11.
Artigo em Inglês | MEDLINE | ID: mdl-34160281

RESUMO

The mud cellar creates a unique microenvironment for the fermentation of strong-flavor baijiu (SFB). Recent research and long-term practice have highlighted the key roles of microbes inhabiting pit mud in the formation of SFB's characteristic flavor. A positive correlation between the quality of SFB and cellar age was extracted from practice; however, the evolutionary patterns of pit mud microbiome and driving factors remain unclear. Here, based on the variation regularity analysis of microbial community structure and metabolites of samples from cellars of different ages (∼30/100/300 years), we further investigated the effects of lactate and acetate (main microbial metabolites in fermented grains) on modulating the pit mud microbiome. Esters (50.3% to 64.5%) dominated the volatile compounds identified in pit mud, and contents of the four typical acids (lactate, hexanoate, acetate, and butyrate) increased with cellar age. Bacteria (9.5 to 10.4 log10 [lg] copies/g) and archaea (8.3 to 9.1 lg copies/g) mainly constituted pit mud microbiota, respectively dominated by Clostridia (39.7% to 81.2%) and Methanomicrobia (32.8% to 92.9%). An upward trend with cellar age characterized the relative and absolute abundance of the most predominant bacterial and archaeal genera, Caproiciproducens and Methanosarcina. Correlation analysis revealed significantly (P < 0.05) positive relationships between the two genera and major metabolites. Anaerobic fermentation with acetate and lactate as carbon sources enhanced the enrichment of Clostridia, and furthermore, the relative abundance of Caproiciproducens (40.9%) significantly increased after 15-day fed-batch fermentation with lactate compared with the initial pit mud (0.22%). This work presents a directional evolutionary pattern of pit mud microbial consortia and provides an alternative way to accelerate the enrichment of functional microbes. IMPORTANCE The solid-state anaerobic fermentation in a mud cellar is the most typical feature of strong-flavor baijiu (SFB). Metabolites produced by microbes inhabiting pit mud are crucial to create the unique flavor of SFB. Accordingly, craftspeople have always highlighted the importance of the pit mud microbiome and concluded by centuries of practice that the production rate of high-quality baijiu increases with cellar age. To deepen the understanding of the pit mud microbiome, we determined the microbial community and metabolites of different-aged pit mud, inferred the main functional groups, and explored the forces driving the microbial community evolution through metagenomic, metabolomic, and multivariate statistical analyses. The results showed that the microbial consortia of pit mud presented a regular and directional evolutionary pattern under the impact of continuous batch-to-batch brewing activities. This work provides insight into the key roles of the pit mud microbiome in SFB production and supports the production optimization of high-quality pit mud.


Assuntos
Archaea/isolamento & purificação , Bactérias/isolamento & purificação , Argila/microbiologia , Aromatizantes/metabolismo , Microbiota , Vinho/análise , Archaea/classificação , Archaea/genética , Archaea/metabolismo , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , China , Fermentação , Aromatizantes/análise , Armazenamento de Alimentos/instrumentação , Vinho/microbiologia
9.
Food Microbiol ; 99: 103764, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34119122

RESUMO

This study investigated the fungal community succession and volatile compound dynamics of Harbin dry sausage during a twelve-day fermentation using high-throughput internal transcribed spacer amplicon sequencing and headspace solid-phase microextraction gas chromatography-mass spectrometry. Aspergillus pseudoglaucus was found to be the primary species in the sausages during fermentation, whereas Lasiodiplodia theobromae, Alternaria alternata, Aspergillus caesiellus, and Trichosporon asahii were also prevalent. Additionally, a total of 72 volatile compounds were identified in the dry sausages, of which 24 key compounds (odor activity value > 1) dominated flavor development, including 3 aldehydes, 1 ketone, 4 alcohols, 9 esters, 4 alkenes, and 3 other compounds. Furthermore, correlation analysis suggested that most of the core fungi were positively correlated with the key volatile compounds, particularly A. pseudoglaucus, Aspergillus gracilis, Trichosporon caseorum, Debaryomyces hansenii, and T. asahii. Our findings provide novel insights into the fungal ecology and flavor development of Harbin dry sausages.


Assuntos
Fungos/isolamento & purificação , Micobioma , Compostos Orgânicos Voláteis/química , Animais , Fermentação , Aromatizantes/química , Aromatizantes/metabolismo , Microbiologia de Alimentos , Fungos/classificação , Fungos/genética , Fungos/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Produtos da Carne/microbiologia , Suínos , Compostos Orgânicos Voláteis/metabolismo
10.
World J Microbiol Biotechnol ; 37(7): 125, 2021 Jun 26.
Artigo em Inglês | MEDLINE | ID: mdl-34173085

RESUMO

Ethyl-acetate is important for the flavor and aroma of the alcoholic beverages, therefore, there have been extensive efforts toward increasing its production by engineering yeast strains. In this study, we reported a new approach to breed non-genetic modified producing yeast strain with higher ethyl-acetate production for beer brewing. First, we demonstrated the positive effect of higher acetic acid concentration on inducing the expression of acetyl-CoA synthetase (ACS). Then, we applied adaptive laboratory evolution method to evolve strain with higher expression level of ACS. As a result, we obtained several evolved strains with increased ACS expression level as well as ethyl-acetate production. In 3 L scale fermentation, the optimal strain EA60 synthesized more ethyl-acetate than M14 at the same time point. At the end of fermentation, the ethyl-acetate production in EA60 was 21.4% higher than M14, while the other flavor components except for acetic acid were changed in a moderate degree, indicating this strain had a bright prospect in industrial application. Moreover, this study also indicated that ACS1 played a more important role in increasing the acetic acid tolerance of yeast, while ACS2 contributed to the synthesis of cytosol acetyl-CoA, thereby facilitating the production of ethyl-acetate during fermentation.


Assuntos
Acetatos/metabolismo , Ácido Acético/metabolismo , Bebidas Alcoólicas/microbiologia , Coenzima A Ligases/metabolismo , Saccharomyces/metabolismo , Adaptação Biológica , Cerveja/microbiologia , Evolução Molecular Direcionada/métodos , Fermentação , Aromatizantes/metabolismo , Microbiologia Industrial/métodos , Laboratórios , Engenharia Metabólica , RNA Fúngico , Reação em Cadeia da Polimerase em Tempo Real , Saccharomyces/genética
11.
Respir Res ; 22(1): 151, 2021 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-34006276

RESUMO

The electronic cigarette (e-cigarette), for many considered as a safe alternative to conventional cigarettes, has revolutionised the tobacco industry in the last decades. In e-cigarettes, tobacco combustion is replaced by e-liquid heating, leading some manufacturers to propose that e-cigarettes have less harmful respiratory effects than tobacco consumption. Other innovative features such as the adjustment of nicotine content and the choice of pleasant flavours have won over many users. Nevertheless, the safety of e-cigarette consumption and its potential as a smoking cessation method remain controversial due to limited evidence. Moreover, it has been reported that the heating process itself can lead to the formation of new decomposition compounds of questionable toxicity. Numerous in vivo and in vitro studies have been performed to better understand the impact of these new inhalable compounds on human health. Results of toxicological analyses suggest that e-cigarettes can be safer than conventional cigarettes, although harmful effects from short-term e-cigarette use have been described. Worryingly, the potential long-term effects of e-cigarette consumption have been scarcely investigated. In this review, we take stock of the main findings in this field and their consequences for human health including coronavirus disease 2019 (COVID-19).


Assuntos
COVID-19/epidemiologia , Sistemas Eletrônicos de Liberação de Nicotina , Aromatizantes/efeitos adversos , Nível de Saúde , Vaping/efeitos adversos , Vaping/epidemiologia , COVID-19/metabolismo , Aromatizantes/metabolismo , Humanos , Vaping/metabolismo
12.
Food Chem Toxicol ; 153: 112290, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34023459

RESUMO

One of the most widely used flavour enhancers in the food industry is monosodium glutamate (MSG). MSG consumption has been on an upward trend, worrying in terms of potential toxic effects. This review is focused on the long-term toxicity of MSG and the experimental evidence that supports it. The article's primary purpose was to survey recently published data regarding the consumption of MSG within safe limits. The administered doses in animal models are very varied and have given rise to controversy. Also, the paper comprises pathways to lower MSG toxicity and highlight other underexploited biological effects, as anti-cancer potential. The administration of MSG, combined with various compounds, has been shown benefit against toxic effects. Several recent studies have identified a possible mechanism that recommends MSG and some derivatives as potential anti-cancer agents. New anti-cancer compounds based on the glutamic acid structure must be studied and further exploited. International regulations require harmonization of safe doses of MSG based on current scientific studies. Replacing MSG with other umami flavour enhancers may be a safer alternative for human health in the future. The biological consequences of MSG consumption or therapeutical administration have not been fully deciphered yet.


Assuntos
Antineoplásicos/toxicidade , Aromatizantes/toxicidade , Neurotransmissores/toxicidade , Glutamato de Sódio/toxicidade , Animais , Antineoplásicos/metabolismo , Antineoplásicos/uso terapêutico , Antioxidantes/farmacologia , Aromatizantes/metabolismo , Glutamatos/uso terapêutico , Glutamina/metabolismo , Humanos , Neurotransmissores/fisiologia , Estresse Oxidativo/efeitos dos fármacos , Glutamato de Sódio/metabolismo
13.
Microb Cell Fact ; 20(1): 109, 2021 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-34049541

RESUMO

BACKGROUND: Plant-based milk alternatives are more popular than ever, and chickpea-based milks are among the most commercially relevant products. Unfortunately, limited nutritional value because of low levels of the essential amino acid L-lysine, low digestibility and unpleasant taste are challenges that must be addressed to improve product quality and meet consumer expectations. RESULTS: Using in-silico screening and food safety classifications, 31 strains were selected as potential L-lysine producers from approximately 2,500 potential candidates. Beneficially, 30% of the isolates significantly accumulated amino acids (up to 1.4 mM) during chickpea milk fermentation, increasing the natural level by up to 43%. The best-performing strains, B. amyloliquefaciens NCC 156 and L. paracasei subsp. paracasei NCC 2511, were tested further. De novo lysine biosynthesis was demonstrated in both strains by 13C metabolic pathway analysis. Spiking small amounts of citrate into the fermentation significantly activated L-lysine biosynthesis in NCC 156 and stimulated growth. Both microbes revealed additional benefits in eliminating indigestible sugars such as stachyose and raffinose and converting off-flavour aldehydes into the corresponding alcohols and acids with fruity and sweet notes. CONCLUSIONS: B. amyloliquefaciens NCC 156 and L. paracasei subsp. paracasei NCC 2511 emerged as multi-benefit microbes for chickpea milk fermentation with strong potential for industrial processing of the plant material. Given the high number of L-lysine-producing isolates identified in silico, this concept appears promising to support strain selection for food fermentation.


Assuntos
Vias Biossintéticas , Aromatizantes/metabolismo , Lactobacillales/genética , Lactobacillales/metabolismo , Lisina/biossíntese , Substitutos do Leite/metabolismo , Açúcares/metabolismo , Cicer/metabolismo , Fermentação , Microbiologia de Alimentos , Genoma Bacteriano , Lactobacillales/isolamento & purificação , Paladar
14.
J Sci Food Agric ; 101(15): 6300-6310, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33969489

RESUMO

BACKGROUND: Strong-flavor baijiu is a traditional distilled alcoholic beverage with a long history in China. The fermented grains play a pivotal role in the production of baijiu. The purpose of this study was to evaluate and compare the microbiota and flavor substances present in fermented zaopei (ZP) from pits of different ages. High-throughput sequencing, headspace solid-phase microextraction gas chromatography-mass spectrometry, principal component analysis, community composition analysis, and redundancy analysis were used to analyze and evaluate the impact of environmental factors on microbial communities and flavor substances. RESULTS: Six genera of bacteria (e.g., Caproiciproducens, Syntrophaceticus, Sedimentibacter, Hydrogenispora, Pelotomaculum and Bacillus) and seven genera of fungi (Cladosporium, Debaryomyces, Dipodascus, Auxarthron, Cephalotrichum, unclassified Stachybotryaceae, unclassified Microascaceae and Cephalotrichum) notably affected the production of hexanoic acid (an important flavor compound). Moisture and alcohol content also had considerable effects on the production of the flavor compounds such as ethyl lactate, hexanoic acid, and ethyl hexanoate. The profiles of volatile compounds present in ZP were different between the aged and new pits; these profiles were mainly reflected in the concentration and types of alcohols, aldehydes, esters, and aromatic compounds. CONCLUSIONS: This paper provides a comprehensive overview of the physicochemical parameters, flavor substances, and microbial population distribution of ZP. Characterization of various ZP samples help to elucidate the fermentation mechanisms and offer a theoretical reference to control and enhance the quality of Baijiu. © 2021 Society of Chemical Industry.


Assuntos
Bebidas Alcoólicas/microbiologia , Bactérias/isolamento & purificação , Aromatizantes/química , Fungos/isolamento & purificação , Fungos/metabolismo , Microbiota , Bebidas Alcoólicas/análise , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , Fermentação , Aromatizantes/metabolismo , Fungos/classificação , Fungos/genética , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Paladar
15.
J Sci Food Agric ; 101(15): 6525-6532, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34002396

RESUMO

BACKGROUND: Chinese te-flavor baijiu (CTF), the most famous Chinese baijiu in Jiangxi province, China, is made from a unique daqu. Its characteristic style is closely related to the daqu used for fermentation. However, current studies on the effects of different production seasons on microbial communities, physicochemical indices, and volatile compounds in CTF daqu are very rare. RESULTS: The relationships of microbial communities, physicochemical indices, and volatile compounds in CTF daqu produced in summer (July and August) and autumn (September and October) were studied. The results of Illumina MiSeq sequencing indicated that there was greater bacterial diversity in the CTF daqu-7 (produced in July) and CTF daqu-8 (produced in August) and greater fungal diversity in the CTF daqu-9 (produced in September) and CTF daqu-10 (produced in October). The physicochemical indices of CTF daqu produced in different seasons were significantly different. It was determined that CTF daqu-9 had the highest esterification and liquefaction abilities. A total of 44 volatile compounds, including alcohols, esters, aldehydes, and ketones were identified in CTF daqu produced during different seasons. Among them, CTF daqu-9 had the greatest alcohol content. CONCLUSION: September (early autumn) is the best production period for CTF daqu. The results of the study provide a theoretical basis for the standardized and uniform production of Chinese baijiu. © 2021 Society of Chemical Industry.


Assuntos
Bactérias/isolamento & purificação , Aromatizantes/química , Fungos/isolamento & purificação , Microbiota , Compostos Orgânicos Voláteis/química , Vinho/microbiologia , Bactérias/classificação , Bactérias/genética , Bactérias/metabolismo , China , Fermentação , Aromatizantes/metabolismo , Fungos/classificação , Fungos/genética , Fungos/metabolismo , Humanos , Estações do Ano , Paladar , Compostos Orgânicos Voláteis/metabolismo , Vinho/análise
16.
Food Microbiol ; 98: 103786, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33875214

RESUMO

This work aimed to evaluate Coffea canephora's microbiological, chemical, and sensory characteristics at 300 and 600 m elevation plantations processed by the natural method inoculated with yeasts. The coffee was spread on suspended terraces and sprayed with approximately 107 cfu/mL of Meyerozyma caribbica CCMA 1738 or Pichia kluyveri CCMA 1743, separately. Cherries containing bark and parchment were collected during fermentation for microbial groups counting, qPCR, quantification of organic acids, and sugars (HPLC). Volatile compounds (GC-MS) and sensory analyses, cupping test with expert coffee tasters and triangular test with consumers, were performed on roasted coffee beans. The inoculated yeasts persisted during the entire fermentation process. M. caribbica reduced the filamentous fungal population by 63% and 90% in the 300- and 600-m coffees, respectively. The 300-m coffee fruits showed higher concentrations of organic acids in all fermentation times when compared to the 600-m reaching out to 8 times more. Twenty-four volatile compounds were identified in the roasted coffee beans, with the predominance of pyrazines. The 600-m coffee inoculated with M. caribbica showed an increase of more than one point in the score given by certified tasters. Consumers noticed the M. caribbica inoculation in the 300- and 600-m-elevation coffees. M. caribbica is a promising starter culture for Conilon coffee with the potential to increase the beverage quality.


Assuntos
Coffea/microbiologia , Aromatizantes/química , Leveduras/metabolismo , Cromatografia Líquida de Alta Pressão , Coffea/química , Coffea/metabolismo , Café/química , Fermentação , Aromatizantes/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Sementes/química , Sementes/metabolismo , Sementes/microbiologia , Paladar , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo , Leveduras/classificação , Leveduras/genética
17.
Food Microbiol ; 98: 103644, 2021 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-33875226

RESUMO

The potential of yeasts isolated from traditional chichas as starter cultures, either for controlled production of the native beverage or for industrial beer production, has been investigated. Three S. cerevisiae strains and one T. delbrueckii strain isolated from four different Ecuadorian chichas were compared to ale and lager beer strains with respect to fermentation performance, sugar utilisation, phenolic off-flavour production, flocculation and growth at low temperature. Fermentations were performed in 15 °P all-malt wort and in a model chicha substrate at 12 °C and 20 °C. Tall-tube fermentations (1.5 L) were also performed with both substrates to assess yeast performance and beer quality. Among the strains tested, only one Ecuadorian S. cerevisiae strain was able to ferment the wort sugars maltose and maltotriose. Fermentations with all Ecuadorian strains were poor in wort at 12 °C relative to 20 °C, but were similar in model chicha substrate at both temperatures. The aromatic profile was different between species and strains. These results indicate the potential of yeasts derived from traditional Andean fermented beverages for commercial applications. One of the chicha strains demonstrated traits typical of domesticated brewery strains and could be suitable for ale fermentation, while the other strains may have potential for low-alcohol beer or chicha production.


Assuntos
Bebidas Alcoólicas/microbiologia , Saccharomyces cerevisiae/metabolismo , Trissacarídeos/metabolismo , Zea mays/microbiologia , Cerveja/microbiologia , Equador , Fermentação , Aromatizantes/química , Aromatizantes/metabolismo , Microbiologia de Alimentos , Maltose/metabolismo , Saccharomyces cerevisiae/classificação , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/crescimento & desenvolvimento , Leveduras/classificação , Leveduras/genética , Leveduras/metabolismo , Zea mays/metabolismo
18.
Food Microbiol ; 97: 103753, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33653526

RESUMO

Saccharomyces cerevisiae has long been part of human activities related to the production of food and wine. The industrial demand for fermented beverages with well-defined and stable characteristics boosted the isolation and selection of strains conferring a distinctive aroma profile to the final product. To uncover variants characterizing oenological strains, the sequencing of 65 new S. cerevisiae isolates, and the comparison with other 503 publicly available genomes were performed. A hybrid approach based on short Illumina and long Oxford Nanopore reads allowed the in-depth investigation of eleven genomes and the identification of putative laterally transferred regions and structural variants. A comparative analysis between clusters of strains belonging to different datasets allowed the identification of novel relevant genetic features including single nucleotide polymorphisms, insertions and structural variants. Detection of oenological single nucleotide variants shed light on the existence of different levels of modulation for the mevalonate pathway relevant for the biosynthesis of aromatic compounds.


Assuntos
Genoma Fúngico , Saccharomyces cerevisiae/genética , Fermentação , Aromatizantes/química , Aromatizantes/metabolismo , Sequenciamento de Nucleotídeos em Larga Escala/instrumentação , Polimorfismo de Nucleotídeo Único , Saccharomyces cerevisiae/classificação , Saccharomyces cerevisiae/metabolismo
19.
World J Microbiol Biotechnol ; 37(5): 75, 2021 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-33779846

RESUMO

In recent years, there had been growing demand for distinctive high quality beer. Fermentation management has a fundamental role in beer quality and the levels of aroma compounds. Use of non-conventional yeast has been proposed to enhance beer flavor. In this study, the bioflavor of traditional sorghum beer from Côte d'Ivoire was investigated. The flavor profile of two beers fermented with wild yeasts and with pure culture of Saccharomyces cerevisiae respectively were studied. The main flavor components of the beer fermented by pure culture of Saccharomyces cerevisiae were different from those of the beer fermented with wild yeasts. The total level of esters and higher alcohols were (173.51 and 128.85 mg/L) respectively in the beer fermented with wild yeasts. These levels were significantly higher than those in the beer fermented with pure culture of Saccharomyces cerevisiae which were 13.08 and 78.26 mg/L for higher alcohols and esters respectively. On the other hand, the beer fermented with pure culture of Saccharomyces cerevisiae had an acid content higher than beer fermented with wild yeasts, i.e. 9.3 mg/L and 7.53 mg/L respectively.


Assuntos
Cerveja/análise , Saccharomyces cerevisiae/metabolismo , Compostos Orgânicos Voláteis/análise , Compostos Orgânicos Voláteis/metabolismo , Leveduras/metabolismo , Ácidos/análise , Ácidos/metabolismo , Álcoois/análise , Álcoois/metabolismo , Cerveja/microbiologia , Costa do Marfim , Ésteres/análise , Ésteres/metabolismo , Fermentação , Aromatizantes/análise , Aromatizantes/química , Aromatizantes/metabolismo , Sorghum/metabolismo , Sorghum/microbiologia , Paladar , Compostos Orgânicos Voláteis/química
20.
J Sci Food Agric ; 101(13): 5618-5626, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33709431

RESUMO

BACKGROUND: Metabolite formation is a physiological stress response during the growth and development of shiitake mushrooms (Lentinula edodes). The characteristic flavor metabolites are important quality components in shiitake mushrooms. To investigate the formation mechanisms of characteristic flavor metabolites, transcriptome analyses were performed on shiitake mushrooms harvested at different growth stages. RESULTS: In total, 30 genes related to the synthesis of characteristic volatiles of mushrooms were identified via screening. Through KEGG (Kyoto Encyclopedia of Genes and Genomes) enrichment analysis of the selected genes and correlation analyses of gene expressions, the main volatile synthesis pathways were determined as histidine metabolism, glutathione metabolism and biosynthesis of unsaturated fatty acids. Gene cluster and correlation analyses were performed to clarify the combined effects of different genes in the enzymatic reactions. Further, a correlation network of candidate genes was built based on the gene expression levels. CONCLUSION: The activities of flavor synthases and the content of characteristic flavor metabolites were analyzed; the enzyme activity changes and metabolic product distribution sites were clarified. A synthesis and regulation network was constructed for the candidate genes and characteristic volatiles, and information was obtained for 16 hub genes. Moreover, it was essential to identify and characterize the key genes and synthases involved in the synthesis of the characteristic volatiles of mushrooms. This information provides us with a better understanding of the biosynthesis and regulation of the volatiles, which will lay the foundation for improving the quality of shiitake mushrooms. © 2021 Society of Chemical Industry.


Assuntos
Aromatizantes/metabolismo , Proteínas Fúngicas/genética , Cogumelos Shiitake/genética , Vias Biossintéticas , Aromatizantes/química , Proteínas Fúngicas/metabolismo , Redes Reguladoras de Genes , Odorantes/análise , Cogumelos Shiitake/química , Cogumelos Shiitake/metabolismo , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo
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