Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 694
Filtrar
1.
Food Res Int ; 190: 113905, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38945555

RESUMO

Bee bread is a product of honeybees, which collect and ferment pollen, that contains highly nutritious and easily digestible active substances. However, its nutritional composition varies significantly with fermentation strains and seasonal changes. To unveil the patterns of microbial community and nutritional component changes in bee bread across seasons, we employed high-throughput techniques to assess the diversity of bacteria and fungi in bee bread. The results indicated that the compositions of bacteria and fungi in bee bread undergo significant seasonal variation, with noticeable changes in the microbial diversity of bee bread from different bee species. Subsequently, metabolomic analysis revealed high activity of glycerophospholipid metabolism in bee bread. Furthermore, our analysis identifaied noteworthy differences in nutritional components, including pH values, sugar content, and free amino acid levels, in bee bread across different seasons.


Assuntos
Bactérias , Microbiota , Valor Nutritivo , Estações do Ano , Abelhas/microbiologia , Animais , Bactérias/classificação , Fermentação , Aminoácidos/análise , Fungos/classificação , Pólen/química , Pão/análise , Pão/microbiologia , Concentração de Íons de Hidrogênio , Metabolômica
2.
Food Res Int ; 190: 114584, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38945604

RESUMO

Levilactobacillus brevis is crucial in food fermentation, particularly in sourdough production. However, the cultivation of L. brevis faces a challenge with accumulation of lactic acid, a major inhibitor. We aimed to increase the acid tolerance of L. brevis, an industrial strain for sourdough fermentation. We used the adaptive laboratory evolution (ALE) to obtain lactic acid tolerant strains. The evolved strain's fermentation and metabolite profiles, alongside sensory evaluation, were compared with the parental strain by using various analytical techniques. The ALE approach increased lactic acid tolerance in the evolved strain showing an increased growth rate by 1.1 and 1.9 times higher than the parental strain at pH 4.1 and 6.5, respectively. Comprehensive analyses demonstrated its potential application in sourdough fermentation, promising reduced downstream costs. The evolved strain, free from genetically modified organisms concerns, has great potential for industrial use by exhibiting enhanced growth in acidic conditions without affecting consumers' bread preferences.


Assuntos
Pão , Fermentação , Microbiologia de Alimentos , Ácido Láctico , Levilactobacillus brevis , Pão/microbiologia , Levilactobacillus brevis/metabolismo , Levilactobacillus brevis/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Ácido Láctico/metabolismo , Paladar , Humanos
3.
Int J Food Microbiol ; 421: 110805, 2024 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-38917489

RESUMO

Due to a large adaptability to different cultivation conditions and limited input compared to other cereals, sorghum is considered an emerging crop. Its antioxidant properties, high fiber content and low glycemic index also make it a valuable addition to a healthy diet, nevertheless, the presence of antinutritional factors and the lack of gluten, hamper its use as food ingredient. This study investigated the impact of sourdough fermentation on sorghum nutritional quality. Lactic acid bacteria dominating sorghum flour and sourdough were identified by culture-dependent analysis revealing Lactiplantibacillus plantarum as the dominant species found in the mature sourdough, whereas Weissella cibaria and Weissella paramesenteroides were the species isolated the most after the first refreshment. Among yeasts, Saccharomyces cerevisiae was the most prevalent. Lactic acid bacteria pro-technological and functional performances as starter were evaluated in sorghum type-II sourdoughs through an integrated characterization combining chromatographic and NMR spectroscopic techniques. The metabolic profile of the strains mainly grouped together W. cibaria strains and W. paramesenteroides AI7 which distinguished for the intense proteolysis but also for the presence of compounds particularly interesting from a physiological perspective (allantoin, glutathione, γ-aminobutyric acid and 2-hydroxy-3-methylbutyric acid), whose concentration increased during fermentation in a species or strain specific matter.


Assuntos
Pão , Fermentação , Farinha , Metaboloma , Sorghum , Sorghum/microbiologia , Pão/microbiologia , Farinha/microbiologia , Farinha/análise , Microbiota , Microbiologia de Alimentos , Saccharomyces cerevisiae/metabolismo , Lactobacillales/metabolismo , Lactobacillales/classificação , Weissella/metabolismo
4.
Food Res Int ; 189: 114482, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38876611

RESUMO

The potential biopreservative role of a Type III sourdough (tIII-SD), produced by starter cultures of Fructilactobacillus sanfranciscensis and Lactiplantibacillus plantarum ATCC 8014, was assessed for its antifungal activity in baking applications. Fermentation was carried out using different substrates to enhance the production of antifungal metabolites for 24 and 48 h. The tIII-SD samples were analyzed in relation to pH, total titratable acidity (TTA) and the production of organic acids. The water/salt-soluble extract of the tIII-SD was evaluated in relation to the inhibition potential against key fungi that contaminate bakery products including Penicillium roqueforti, Penicillium chrysogenum and Aspergillus niger. Finally, breads with 10 % of the tIII-SD were prepared and the fungi contamination was evaluated throughout the shelf life period. The lowest pH value in sourdough was obtained from 48-hour fermentation by L. plantarum. The saline extracts exhibited varying degrees of inhibition in the in vitro test; however, the greatest enhancement of this effect was obtained when whole wheat grain flour was used. The tIII-SD crafted from a blend of wheat and flaxseed flours and fermented with F. sanfranciscensis for 48 h (BSWF48h-FS), demonstrated superior performance compared to other formulations. This variant exhibited a total shelf life of 10 days, suggesting that the utilization of tIII-SD could serve as a viable alternative for natural antifungal agents, proving beneficial for the bakery industry.


Assuntos
Antifúngicos , Pão , Fermentação , Microbiologia de Alimentos , Pão/microbiologia , Pão/análise , Antifúngicos/farmacologia , Aspergillus niger/efeitos dos fármacos , Penicillium/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Farinha/análise , Conservação de Alimentos/métodos , Triticum/química , Triticum/microbiologia , Penicillium chrysogenum , Lactobacillus plantarum/metabolismo
5.
Sci Rep ; 14(1): 14112, 2024 06 19.
Artigo em Inglês | MEDLINE | ID: mdl-38898132

RESUMO

Hybrid development is one of the most promising strategies for boosting crop yields. Parental lines used to create hybrids must have good per se performance and disease resistance for developing superior hybrids. Indian wheat line HD3209 was developed by introducing the rust resistance genes Lr19/Sr25 into the background of popular wheat variety HD2932. The wheat line HD3209 carrying Lr19/Sr25 has been successfully and rapidly converted to the CMS line A-HD3209, with 96.01% background genome recovery, based on selection for agro-morphological traits, rust resistance, pollen sterility, and foreground and background analyses utilizing SSR markers. The converted CMS line A-HD3209 was completely sterile and nearly identical to the recurrent parent HD3209. Based on high per se performance and rust resistance, the study concludes that the derived CMS line A-HD3209 is promising and can be employed successfully in hybrid development.


Assuntos
Resistência à Doença , Genótipo , Doenças das Plantas , Triticum , Triticum/genética , Triticum/microbiologia , Resistência à Doença/genética , Doenças das Plantas/microbiologia , Doenças das Plantas/genética , Basidiomycota/genética , Melhoramento Vegetal/métodos , Genes de Plantas , Hibridização Genética , Pão/microbiologia
6.
Int J Biol Macromol ; 272(Pt 1): 132906, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38851991

RESUMO

Sourdough bread enriched with soluble fiber (by in-situ exopolysaccharides production) and insoluble fiber (by gazpacho by-products addition) showed prebiotic effects an in vitro dynamic colonic fermentation performance with obese volunteer's microbiota. Bifidobacterium population was maintained whereas Lactobacillus increased throughout the colonic sections. Conversely, Enterobacteriaceae and Clostridium groups clearly decreased. Specific bacteria associated with beneficial effects increased in the ascending colon (Lactobacillus fermentum, Lactobacillus paracasei, Bifidobacterium longum and Bifidobacterium adolescentis) whereas Eubacterium eligens, Alistipes senegalensis, Prevotella copri and Eubacterium desmolans increased in the transversal and descending colon. Additionally, Blautia faecis and Ruminococcus albus increased in the transversal colon, and Bifidobacterium longum, Roseburia faecis and Victivallis vadensis in the descending colon. Bifidobacterium and Lactobacillus fermented the in-situ exopolysaccharides and released pectins from gazpacho by-products, as well as cellulosic degraded bacteria. This increased the short and medium chain fatty acids. Acetic acid, as well as butyric acid, increased throughout the colonic tract, which showed greater increases only in the transversal and descending colonic segments. Conversely, propionic acid was slightly affected by the colonic fermentation. These results show that sourdough bread is a useful food matrix for the enrichment of vegetable by-products (or other fibers) in order to formulate products with microbiota modulatory capacities.


Assuntos
Pão , Disbiose , Fermentação , Pão/microbiologia , Humanos , Disbiose/microbiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Fibras na Dieta/metabolismo , Polissacarídeos Bacterianos/farmacologia , Colo/microbiologia , Colo/metabolismo , Bifidobacterium/metabolismo , Masculino , Lactobacillus/metabolismo
7.
Int J Biol Macromol ; 272(Pt 1): 132729, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38821307

RESUMO

This study investigated the effects of foxtail millet sourdough fermentation time (0, 8, 16, and 24 h) on the protein structural properties, thermomechanical, fermentation, dynamic rheological, starch granules crystalline regions molecular mobility, and starch microstructural characteristics. The fermentation led to a significant increase in the concentration of free amino acids from protein hydrolysis. Fourier transform infrared spectroscopy (FTIR) revealed changes in protein secondary structure and the presence of functional groups of different bioactive compounds. The result of thermomechanical properties showed a significant increase in the stability (0.70-0.79 min) and anti-retrogradation ability (2.29-3.14 Nm) of lactic acid bacteria (LAB) sourdough compared to the control dough, showing a wider processing applicability with radar profiler index. In contrast, sourdoughs with lower tan δ values had higher elasticity and strength. Scanning electron microscopy showed that the surface of the starch appeared from smooth to uneven with patchy shapes and cavities, which declined the crystallinity from 34.00 % to 21.57 %, 23.64 %, 25.09 %, and 26.34 % respectively. Fermentation changed the To, Tp, Tc, and ΔH of the starch. The results of the study will have great potential for application in the whole grain sourdough industry.


Assuntos
Fermentação , Amido , Amido/química , Amido/metabolismo , Setaria (Planta)/química , Setaria (Planta)/metabolismo , Grão Comestível/química , Grão Comestível/microbiologia , Pão/microbiologia , Proteínas de Plantas/química , Proteínas de Plantas/metabolismo , Farinha/microbiologia , Reologia
8.
Int J Food Microbiol ; 418: 110730, 2024 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-38714095

RESUMO

Aerobic spore-forming (ASF) bacteria have been reported to cause ropiness in bread. Sticky and stringy degradation, discoloration, and an odor reminiscent of rotting fruit are typical characteristics of ropy bread spoilage. In addition to economic losses, ropy bread spoilage may lead to health risks, as virulent strains of ASF bacteria are not uncommon. However, the lack of systematic approaches to quantify physicochemical spoilage characteristics makes it extremely difficult to assess rope formation in bread. To address this problem, the aim of this study was to identify, characterize and objectively assess the spoilage potential of ASF bacteria associated with ropy bread. Hence, a set of 82 ASF bacteria, including isolates from raw materials and bakery environments as well as strains from international culture collections, were identified by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI-TOF-MS) and their species identity confirmed by 16S rRNA and gyrA or panC gene sequencing. A standardized approach supported by objective colorimetric measurements was developed to assess the rope-inducing potential (RIP) of a strain by inoculating autoclaved bread slices with bacterial spores. In addition, the presence of potential virulence factors such as swarming motility or hemolysis was investigated. This study adds B. velezensis, B. inaquosorum and B. spizizenii to the species potentially implicated of causing ropy bread spoilage. Most importantly, this study introduces a standardized classification protocol for assessing the RIP of a bacterial strain. Colorimetric measurements are used to objectively quantify the degree of breadcrumb discoloration. Furthermore, our results indicate that strains capable of inducing rope spoilage in bread often exhibit swarming motility and virulence factors such as hemolysis, raising important food quality considerations.


Assuntos
Pão , Microbiologia de Alimentos , Pão/microbiologia , Esporos Bacterianos/crescimento & desenvolvimento , Bactérias Aeróbias/isolamento & purificação , Bactérias Aeróbias/classificação , Bactérias Aeróbias/genética , Bactérias Aeróbias/crescimento & desenvolvimento , RNA Ribossômico 16S/genética , Fatores de Virulência/genética , Contaminação de Alimentos/análise , Espectrometria de Massas por Ionização e Dessorção a Laser Assistida por Matriz
10.
Int J Food Microbiol ; 417: 110705, 2024 Jun 02.
Artigo em Inglês | MEDLINE | ID: mdl-38640815

RESUMO

The effect of a casein hydrolysate (CH) on the fermentation and quality of a naturally-fermented buckwheat sourdough (NFBS) were investigated, through assessing the fermentation characteristics, carbohydrate and protein degradation, texture, and bacterial composition of NFBS. According to the assaying data, CH might both increase the amount of lactic acid bacteria by 2.62 % and shorten the fermentation period by at least 3 h, subsequently leading to enhanced degradation of carbohydrate and protein, accompanied by a softer texture. More importantly, CH increased the relative abundance of lactobacillus in NFBS, making it the dominant bacterial genus and inhibited the growth of spoilage bacteria. In addition, Spearman correlation analysis indicated that the pH value, lactic and acetic acid contents, carbohydrates, protease activity, and these textural indices like hardness, elasticity, and adhesion had a positive/negative correlation with the bacterial composition of NFBS (Spearman correlation coefficient: -0.93-0.95). CH was thus regarded to be helpful to NFBS processing and production mainly by shortening its fermentation time, improving its fermentation performance, causing a finer texture and microstructure, and changing bacterial composition.


Assuntos
Pão , Caseínas , Fagopyrum , Fermentação , Fagopyrum/química , Pão/microbiologia , Caseínas/metabolismo , Microbiologia de Alimentos , Lactobacillus/metabolismo , Lactobacillus/crescimento & desenvolvimento , Concentração de Íons de Hidrogênio , Bactérias/metabolismo , Bactérias/crescimento & desenvolvimento , Alimentos Fermentados/microbiologia
11.
J Food Prot ; 87(6): 100280, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38642807

RESUMO

A validation study was conducted to investigate the effect of the English muffin baking process to control Salmonella contamination and to study the thermal inactivation kinetic parameters (D- and z-values) of Salmonella in English muffin dough. The unbleached bread flour was inoculated with 3 serovar Salmonella cocktail (Salmonella serovars viz., Newport, Typhimurium, and Senftenberg), and dried back to its preinoculated water activity levels with 7.46 ± 0.12 log CFU/g of Salmonella concentration. The Salmonella inoculated flour was used to prepare English muffin batter and baked at 204.4°C (400°F) for 18 min and allowed to cool at ambient air for 15 min. The English muffins reached 99 ± 0°C (211.96 ± 0.37°F) as their maximum mean internal temperature during baking. The pH and aw of English muffin dough were 5.01 ± 0.01 and 0.947 ± 0.003, respectively. At the end of the 18-min baking period, the Salmonella inoculated English muffins recorded a more than 5 log CFU/g reduction on the injury-recovery media. The D-values of 3 serovar cocktails of Salmonella at 55, 58.5, and 62°C were 42.0 ± 5.68, 15.6 ± 0.73, and 3.0 ± 0.32 min, respectively; and the z-value was 6.2 ± 0.59°C. The water activity (aw) of the English muffin crumb (0.947 ± 0.003 to 0.9557 ± 0.001) remained statistically unchanged during baking, whereas the aw of the muffin crust decreased significantly (0.947 ± 0.003 to 0.918 ± 0.002) by the end of 18 min of baking. This study validates and documents the first scientific evidence that baking English muffins at 204.4°C (400°F) for 18 min acts as an effective kill step by controlling Salmonella population by >5 log CFU/g.


Assuntos
Contagem de Colônia Microbiana , Contaminação de Alimentos , Microbiologia de Alimentos , Salmonella , Contaminação de Alimentos/prevenção & controle , Contaminação de Alimentos/análise , Pão/microbiologia , Humanos , Manipulação de Alimentos/métodos , Culinária , Farinha/microbiologia , Cinética
12.
Annu Rev Food Sci Technol ; 15(1): 265-282, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38271645

RESUMO

Using sourdough in breadmaking can enhance bread's shelf-life and flavor compared to exclusive baker's yeast use and is believed to increase its nutritional quality and healthiness. Previous research established insight into the microbial ecology of sourdough, but the link between leavening agent use, processing, and bread quality remains elusive. However, such knowledge is key for standardization, research on the health benefits, and the definition of sourdough bread. In this systematic scoping review, we analyzed 253 studies and identified large variations in the type and amount of leavening agent, fermentation conditions, and bread quality (specific loaf volume and acidification). The interrelation between these elements and their effect on the extent of fermentation is discussed, together with issues preventing proper comparison of breadmaking procedures. With this review, we want to contribute to the dialogue concerning the definition of sourdough-type bread products and the research into the health benefits attributed to them.


Assuntos
Pão , Fermentação , Triticum , Pão/microbiologia , Manipulação de Alimentos , Humanos , Microbiologia de Alimentos , Paladar , Valor Nutritivo
13.
Int J Food Microbiol ; 413: 110590, 2024 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-38280258

RESUMO

Fungi are the main microorganisms responsible for the spoilage of bakery products, and their control and subsequent reduction of food waste are significant concerns in the agri-food industry. Synthetic preservatives are still the most used compounds to reduce bakery product spoilage. On the other hand, studies have shown that biopreservation can be an attractive approach to overcoming food and feed spoilage and increasing their shelf-life. However, limited studies show the preservation effects on real food matrices. Therefore, this study aimed to investigate the influence of microorganisms such as lactic acid bacteria (LAB) and yeasts on the growth of spoilage filamentous fungi (molds) on bread and panettones. In general, on conventional and multigrain bread, treatments containing Limosilactobacillus fermentum IAL 4541 and Wickerhamomyces anomalus IAL 4533 showed similar results when compared to the negative control (calcium propionate) in delaying the fungal growth of the tested species (Aspergillus chevalieri, Aspergillus montevidensis, and Penicillium roqueforti). Different from bread, treatments with W. anomallus in panettones delayed the A. chevalieri growth up to 30 days, 13 days longer than observed on negative control (without preservatives). This study showed that biopreservation is a promising method that can extend bakery products' shelf-life and be used as an alternative to synthetic preservatives.


Assuntos
Limosilactobacillus fermentum , Eliminação de Resíduos , Saccharomycetales , Alimentos , Fungos , Conservação de Alimentos/métodos , Microbiologia de Alimentos , Pão/microbiologia
14.
Int J Food Microbiol ; 410: 110505, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38043377

RESUMO

Fermentation has recently been rediscovered as an attractive technique to process legumes, as it can improve the nutritional quality and value of the end product. This study investigated the dynamics and stability of the microbial communities in spontaneously fermented sourdoughs made from flours of two cultivars of faba beans and two cultivars of peas. Sourdoughs were established by the backslopping technique, and the microbial development at 22 °C and 30 °C was followed by culture dependent and culture independent methods. The utilization of substrates and formation of metabolites were also determined by high-performance liquid chromatography. A stable pH was reached in all the sourdoughs after 11-15 days of daily backslopping. Lactic acid bacteria and yeast from pH stable sourdoughs were isolated, characterized and identified. The fermentation temperature influenced the development of the microbial community and the substrate utilization during spontaneous fermentation. In the 30 °C fermentations, one species dominated (Lactiplantibacillus plantarum/pentosus), a lower pH was achieved, and the available substrates were more extensively converted. The 22 °C fermentation resulted in a more diverse microbial community (Lactiplantibacillus, Leuconostoc, Pediococcus), a higher pH, and more residual substrates were available after fermentation. Yeasts were only detected in one of the pea sourdoughs fermented at 30 °C, with Saccharomyces cerevisiae being the dominant species. Nearly all sourdoughs were depleted of maltose after 24 h fermentation cycles, and higher levels of lactic and acetic acid were detected in 30 °C fermen-tations. This research adds to our understanding of the autochthonous microbial community present in faba beans and peas as well as their natural capacity to establish themselves and ferment legume flours. These findings enhance the possibilities of utilizing and improving plant based protein sources.


Assuntos
Fabaceae , Microbiota , Vicia faba , Fermentação , Saccharomyces cerevisiae , Pediococcus , Verduras , Farinha/microbiologia , Pão/microbiologia , Microbiologia de Alimentos
15.
Int J Food Microbiol ; 410: 110513, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38043376

RESUMO

Thirty strains of lactic acid bacteria (LAB) and Saccharomyces cerevisiae E8.9 (wild type) were used to formulate fifteen combinations of starters by mixing two or three LAB with the yeast (ratio LAB: yeast, 10: 1). Such combinations were used to prepare rye sourdough and their performance in term of acidification and biochemical characteristics during fermentation at two temperatures (30 and 37 °C) and duration (4 and 8 h) were screened. The best thirteen sourdough formulations were selected and used for rye crispbread making. The analysis of acrylamide concentration demonstrated that 11 out 13 formulations resulted in significant decreases of concentration compared to the baker's yeast (control), with reductions up to 79.6 %. The rye sourdough crispbreads showed also higher amount of volatile organic compounds (VOCs) compared to the baker's yeast control. Two rye sourdough crispbreads, selected to represent the opposite extremes within the thirteen formulations in term of VOC profiles and fermentation performances, demonstrated better sensory and nutritional features, such as phytic acid reduction (up to 47.3 %), and enhanced total free amino acid compared to the control. These evidences suggest the potential of tailored sourdough fermentations as alternative and suitable biotechnological strategy for lowering acrylamide levels in rye crispbread.


Assuntos
Lactobacillales , Saccharomyces cerevisiae , Fermentação , Saccharomyces cerevisiae/metabolismo , Secale/química , Secale/microbiologia , Pão/microbiologia , Acrilamidas/metabolismo , Farinha/microbiologia
16.
Int J Food Microbiol ; 410: 110487, 2024 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-38035403

RESUMO

Sourdough fermentation is attracting growing attention because of its positive effects on properties of leavened baked good. However, the changes in dough features and the mechanisms behind them are not well understood, which limits its widespread use. In this study, we assessed the effects of representative lactic acid bacteria in sourdough monoculture or co-culture with yeasts on dough characteristics. Physicochemical analysis identified increased proteolysis and enhanced nutritional properties of co-culture groups. However, a reduction in organic acids contents of co-culture groups compared to monoculture was detected, and this effect was not limited by the yeast species. The RNA sequencing further demonstrated that the presence of yeast enhanced the protein metabolic activity of lactic acid bacteria, while decreased its organic acid biosynthetic activity. Moreover, the proteomic analysis revealed that endogenous metabolic proteins of flour, such as pyruvate kinase, glucosyltransferase and pyruvate dehydrogenase play a key role in carbohydrate metabolism during fermentation. This study uncovered the influence of typical microorganisms and endogenous enzymes on dough characteristics based on different aspects. Bacteria-mediated consumption of proteins and increased proteolysis in co-culture groups may underlie the improved digestibility and nutritional effects of sourdough fermented products, which provides an important basis for nutrient fortified bread making with multi-strain leavening agent.


Assuntos
Alimentos Fermentados , Lactobacillales , Microbiota , Fermentação , Proteômica , Leveduras/metabolismo , Pão/microbiologia , Farinha/microbiologia , Carboidratos , Alimentos Fermentados/análise , China
17.
J Agric Food Chem ; 71(48): 18973-18985, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37915201

RESUMO

Chinese steamed bread (CSB) made with commercial yeasts and traditional Chinese sourdoughs was analyzed for the flavor and microbial communities. Sensory attributes were assessed using quantitative descriptive analysis (QDA). Results showed that commercial yeast CSB-1 (JMMT1), a yeast-based sample, had stronger milky and sweet attributes, while commercial yeast CSB-2 (JMMT2) had more pronounced yeasty attributes. Among the sourdough-based samples, Shandong traditional sourdough steamed bread (SDMT) exhibited a winelike character with a weak sweet aftertaste, whereas Shanxi traditional sourdough steamed bread (SXMT) had a distinct sour attribute and a less prominent floury taste. SAFE-GC-O-MS analysis identified 40 aroma compounds with FD values ≥2, including 33 key aroma compounds with an OAV of ≥1. Compounds such as 2,3-butanediol, decanal, methyl isobutenyl ketone, gamma-nonanolactone, ethyl caprate, 2-ethylhexyl acetate, vanillin, and indole contributed significantly to the diverse aroma profiles. High-throughput sequencing revealed dominant strains: Bacillus in JMMT1, Lactobacillus in JMMT2, Bacillus in SDMT, and Lactobacillus in SXMT. Over two-thirds of the aroma compounds showed correlations with microorganisms. Notably, Acetobacter exhibited a highly significant correlation with butanoic acid, while Lactobacillus played a significant role in the formation of ester flavors. These findings contribute to the flavor evaluation and microbial community analysis of steamed bread made with different leavening agents, providing valuable insights into their relationship.


Assuntos
Pão , Microbiota , Saccharomyces cerevisiae , Pão/microbiologia , Fermentação , Lactobacillus , Saccharomyces cerevisiae/genética , Bacillus
18.
J Microbiol Biotechnol ; 33(12): 1671-1680, 2023 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-37915231

RESUMO

The gluten protein content in whole-wheat flour is low, which affects the elasticity and viscosity of the dough. Enzymatic modification of the protein may result in a network that mimics gluten, which plays an important role in the processing of whole-wheat foods. In this study, the effects of Halomonas alkaliantartica laccase (LacHa) on the quality parameters of whole-wheat bread were investigated. The optimum dosage of LacHa was 4 U/100 g of whole-wheat flour. At this dosage, whole-wheat bread exhibited the best specific volume and optimum texture parameters. Laccase also extended the storage duration of whole-wheat bread. We analyzed the micro-structure of the dough to determine its gluten-free protein extractable rate and free sulfhydryl group content, and verify that LacHa mediates cross-linking of gluten-free proteins. The results demonstrated that the cross-linking of gluten-free protein by LacHa improves the texture of whole-wheat bread. As a flour improver, LacHa has great developmental and application potential in baked-food production.


Assuntos
Lacase , Triticum , Lacase/metabolismo , Triticum/metabolismo , Pão/microbiologia , Farinha , Glutens/química
19.
World J Microbiol Biotechnol ; 39(12): 331, 2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37798570

RESUMO

The present study aimed at characterizing lactic acid bacteria (LAB) strains isolated from traditional sourdoughs collected in different regions of Morocco. Isolated strains were firstly identified using Gram staining and catalase reaction test. Presumptive LAB strains were then checked for various phenotypical properties including growth at 45 °C, resistance to NaCl, enzyme production, acidification capacity, diacetyl and exopolysaccharide (EPS) production, and antifungal activity. Finally, selected LAB strains were identified using 16S rDNA sequencing. Results showed that 32.1% of the isolates were thermophilic (45 °C) and 83.9% were resistant to NaCl (6.5%). Moreover, 51.7 and 37.5% were able to produce diacetyl and EPS, respectively. Regarding enzyme production, 55.3 and 7.1% of the isolates showed lipolytic and proteolytic activities, respectively. Low pH values (3.37-3.76) were obtained after 24 h of incubation of LAB strains in de Man, Rogosa and Sharpe (MRS) broth. Antifungal activity test against Aspergillus flavus, Aspergillus niger and Penicillium spp. showed an inhibition rate up to 50%. Bacterial DNA sequencing showed that LAB isolates belong to seven species, chiefly Levilactobacillus brevis, Lentilactobacillus parabuchneri, Lactiplantibacillus plantarum, Pediococcus pentosaceus, Enterococcus hirae, Bifidobacterium pseudocatenulatum, and Companilactobacillus paralimentarius. These findings, for the first time in Moroccan sourdoughs, indicate that the isolated LAB strains have good multifunctional properties and could be suitable as good starters for sourdough bread production under controlled conditions.


Assuntos
Lactobacillales , Humanos , Antifúngicos , Diacetil , Cloreto de Sódio , Fermentação , Biodiversidade , Pão/microbiologia , Microbiologia de Alimentos
20.
Int J Food Microbiol ; 407: 110402, 2023 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-37778079

RESUMO

Sourdough starters harbor microbial consortia that benefit the final product's aroma and volume. The complex nature of these spontaneously developed communities raises challenges in predicting the fermentation phenotypes. Herein, we demonstrated for the first time in this field the potential of genome-scale metabolic modeling (GEMs) in the study of sourdough microbial communities. Broad in-silico modeling of microbial growth was applied on communities composed of yeast (Saccharomyces cerevisiae) and different Lactic Acid Bacteria (LAB) species, which mainly predominate in sourdough starters. Simulations of model-represented communities associated specific bacterial compositions with sourdough phenotypes. Based on ranking the phenotypic performances of different combinations, Pediococcus spp. - Lb. sakei group members were predicted to have an optimal effect considering the increase in S. cerevisiae growth abilities and overall CO2 secretion rates. Flux Balance Analysis (FBA) revealed mutual relationships between the Pediococcus spp. - Lb. sakei group members and S. cerevisiae through bidirectional nutrient dependencies, and further underlined that these bacteria compete with the yeast over nutrients to a lesser extent than the rest LAB species. Volatile compounds (VOCs) production was further modeled, identifying species-specific and community-related VOCs production profiles. The in-silico models' predictions were validated by experimentally building synthetic sourdough communities and assessing the fermentation phenotypes. The Pediococcus spp. - Lb. sakei group was indeed associated with increased yeast cell counts and fermentation rates, demonstrating a 25 % increase in the average leavening rates during the first 10 fermentation hours compared to communities with a lower representation of these group members. Overall, these results provide a possible novel strategy towards the de-novo design of sourdough starter communities with tailored-made characterizations, including a shortened leavening period.


Assuntos
Lactobacillales , Fermento Seco , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Fermentação , Lactobacillales/metabolismo , Bactérias , Pediococcus , Pão/microbiologia , Farinha/microbiologia , Microbiologia de Alimentos
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...