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1.
An Acad Bras Cienc ; 96(suppl 1): e20240083, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39258700

RESUMO

Fermentation using starter cultures has been considered an alternative and economically viable technology for the production of specialty coffees. This type of technology promotes several benefits, such as increased sensory quality, control over the fermentation process, predictability of the final product and added value. Coffee (Coffea arabica L.) samples for this study were collected in Presidente Olegário - MG (2018/19 crop year) in the Cerrado region of Minas Gerais. The effects of natural fermentation and inoculation of the yeast Torulaspora delbrueckii and duration of fermentation (0, 24, 48, 72 and 96 hours) on the sensory and chemical quality (analysis of bioactive, volatile, and organic compounds and fatty acids) of coffee were evaluated. The objective of this study was to determine the effect of fermentation time and starter culture inoculation on the chemical composition of fermented coffees. Fermentation time significantly influenced the sensory description of the coffee beverage, with notes of honey, brown sugar and almond predominating up to 48 hours, for coffees fermented for 72 and 96 hours the notes described were and fruity, winey notes. The chemical composition was primarily influenced by fermentation time.


Assuntos
Coffea , Café , Fermentação , Café/química , Café/microbiologia , Fatores de Tempo , Coffea/química , Coffea/microbiologia , Paladar , Torulaspora/metabolismo
2.
FEMS Yeast Res ; 232023 01 04.
Artigo em Inglês | MEDLINE | ID: mdl-36958847

RESUMO

Yeasts are important microorganisms used in different fermentation processes. The cocoa beans must go through a correct fermentation process to obtain good-quality chocolate, which involves the action of yeasts and bacteria, and yeasts play a crucial role since they act in the first days of fermentation. In coffee, several studies have shown that the microbiota in the fruits is also a relevant factor. The fermentation process (regardless of the processing type) improves the beverage's quality. In this sense, studies using starter cultures in these two raw materials are important for better control of the process, and optimization of fermentation time, in addition to the improvement and diversification of volatile and non-volatile compounds produced by yeasts. Thus, this review discusses the importance and role of yeasts during fermentation, their metabolism, the produced compounds, and how yeast and the different chemical reactions help increase the quality of chocolate and coffee.


Assuntos
Cacau , Chocolate , Fermentação , Café/metabolismo , Café/microbiologia , Leveduras/metabolismo , Cacau/química , Cacau/metabolismo , Cacau/microbiologia , Saccharomyces cerevisiae/metabolismo
3.
J Appl Microbiol ; 134(1)2023 Jan 23.
Artigo em Inglês | MEDLINE | ID: mdl-36626744

RESUMO

AIM: This work evaluated the microbial diversity and physicochemical characteristics of fresh and fermented fruits from Brazilian untreated green table olives of the Ascolano and Grappolo cultivars. METHODS AND RESULTS: Twenty species of mesophilic bacteria, seven lactic acid bacteria, and fourteen yeast were identified. Some species prevailed over others, such as the bacteria Levilactobacillus brevis, Lacticaseibacillus paracasei subsp. paracasei, Pantoea agglomerans, Staphylococcus warneri, Bacillus simplex, B. thuringiensis, and the yeasts Candida parapsilosis, Ca. orthopsilosis, and Cryptococcus flavescen. In the olive fruit and olive brine, the sugars: sucrose, glucose, mannitol, and fructose, and the acids: acetic, citric, lactic, malic, and succinic were identified. Thirty-seven volatile compounds belonging to different chemical classes of acids, alcohols, aldehydes, esters, hydrocarbons, phenols, ketones, and ether were identified in the fruits and brine olives. CONCLUSION: The polyphasic methodology using matrix assisted laser desorption/ionization-time of flight and 16S rRNA sequencing was efficiently performed to identify microorganisms; chemical analysis helped to understand the fermentation process of olives.


Assuntos
Olea , Olea/microbiologia , Brasil , RNA Ribossômico 16S/genética , Leveduras/genética , Bactérias/genética , Saccharomyces cerevisiae/genética , Fermentação , Microbiologia de Alimentos
4.
Food Microbiol ; 110: 104161, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36462817

RESUMO

This work aimed to evaluate the impact of inoculation single and co-cultivation of LAB and yeasts during the wet process of Coffea canephora using the self-induced anaerobic fermentation method. Saccharomyces cerevisiae, Totulaspora delbrueckii delbrueckii, Leuconostoc mesenteroides, and Lactiplantibacillus plantarum were monitored during fermentation. L. mesenteroides was detected in high concentrations in the coffee fruits (8.54 log10 cells/mL) and remained until the end of fermentation. Lactic and acetic acids were the main acids produced during fermentation. After 36 h of fermentation, 75.39% of malic acid was consumed in the L. mesenteroides + S. cerevisiae (MC) fermentations. In roasted coffee, the caffeine concentration reached 3.29 higher than the green beans in MC fermentation. Specific volatile compounds were detected in inoculated fermentation and may contribute to the beverage quality. Coffee inoculated with Leuconostoc mesenteroides was classified as fine (80.0-89.0), while the other fermentations were classified as premium (70.0-79.0). L. mesenteroides inoculation showed the best sensory score, and the beverage was characterized by caramel, fruity, and spices notes. L. mesenteroides inoculated alone or in co-culture with S. cerevisiae are promising starter cultures to improve Conilon coffee quality and obtain beverages with differentiated sensory profiles.


Assuntos
Coffea , Lactobacillales , Leuconostoc mesenteroides , Café , Fermentação , Saccharomyces cerevisiae , Anaerobiose
5.
J Basic Microbiol ; 63(6): 658-667, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36734187

RESUMO

Fungi, yeasts and bacteria produce volatile compounds during their metabolism. In this study, the volatile compounds produced by yeast strains (Saccharomyces cerevisiae and Rhodotorula mucilaginosa) and fungal strains (Aspergillus carbonarius and Aspergillus ochraceus) during competitive interactions were investigated by solid-phase microextraction coupled with gas chromatography-mass spectrometry. Fifty-six volatile compounds were identified representing alcohols, aldehydes, esters, ketones, aromatic compounds, acids, furans, phenols, and nitrogen compounds, being the largest amount in the class of esters and alcohols. Eight compounds were identified only in interactive culture conditions such as 2-amino-1-propanol, isopropylamine, dimethylamine, pentyl propanoate, ethyl-2-aminopropanoate, acetone, oxalic acid, and ß-elemene and five of these were produced in cocultures including A. carbonarius. These will be developed for future biotechnological applications such as in the pharmaceutical and biological industry to produce drugs. Antimicrobial and antifungal activities; Solvent and herbicide; flavoring ingredient; solvent, plastic synthesis, nail polish remover and thinner, pesticide and herbicide; important in the complexation of minerals in the soil; and plant-environment interactions, defending predators, pathogens, and competitors.


Assuntos
Herbicidas , Compostos Orgânicos Voláteis , Leveduras/metabolismo , Álcoois/análise , Álcoois/química , Álcoois/metabolismo , Saccharomyces cerevisiae/metabolismo , Solventes , Ésteres/análise , Herbicidas/metabolismo , Compostos Orgânicos Voláteis/química
6.
World J Microbiol Biotechnol ; 39(4): 91, 2023 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-36752862

RESUMO

Microorganisms isolated from contaminated areas play an important role in bioremediation processes. They promote heavy metal removal from the environment by adsorbing ions onto the cell wall surface, accumulating them inside the cells, or reducing, complexing, or precipitating these substances in the environment. Microorganism-based bioremediation processes can be highly efficient, low-cost and have low environmental impact. Thus, the present study aimed to select Pb2+-resistant bacteria and evaluate the growth rate, biological activity, and the presence of genes associated with metal resistance. Serratia marcescens CCMA 1010, that was previously isolated from coffee processing wastewater, was selected since was able to growth in Pb2+ concentrations of up to 4.0 mM. The growth rate and generation time did not differ from those of the control (without Pb2+), although biological activity decreased in the first hour of exposure to these ions and stabilized after this period. The presence of the zntR, zntA and pbrA genes was analysed, and only zntR was detected. The zntR gene encodes a protein responsible for regulating the production of ZntA, a transmembrane protein that facilitates Pb2+ extrusion out of the cell. S. marcescens CCMA 1010 demonstrated a potential for use as bioindicator that has potential to be used in bioremediation processes due to its resistance to high concentrations of Pb2+, ability to grow until 24 h of exposure, and possession of a gene that indicates the existence of mechanisms associated with resistance to lead (Pb2+).


Assuntos
Metais Pesados , Purificação da Água , Cádmio/metabolismo , Serratia marcescens/genética , Serratia marcescens/metabolismo , Chumbo/metabolismo , Metais Pesados/metabolismo , Íons/metabolismo , Biodegradação Ambiental
7.
Food Microbiol ; 103: 103962, 2022 May.
Artigo em Inglês | MEDLINE | ID: mdl-35082079

RESUMO

Microbial communities associated with coffee fermentation have been widely investigated. However, few reports about self-induced anaerobiosis fermentation (SIAF) on microbial diversity and the chemical and sensory profile of coffees grown under different environmental conditions have been studied. This study evaluated the microbial, chemical, and sensorial profile of the natural and pulped coffee fermented with and without induced anaerobiosis. The microbial diversity was determined by plating and next-generation sequencing, the chemical profile through 1H NMR and chemometrics analysis, and sensory analysis was conducted by Temporal Dominance of Sensations (TDS). Three hundred and eighty microorganisms were isolated; 149 mesophilic bacteria, 147 lactic acid bacteria, and 84 yeasts. Hanseniaspora uvarum, Lactiplantibacillus plantarum, Leuconostoc mesenteroides, and Weissella cibaria were identified in Monte Carmelo, Três Pontas, Carmo de Minas, and Lajinha in Minas Gerais, Brazil. New generation sequencing (NGS) analysis identified a high yeast species diversity (74). Some metabolites such as chlorogenic acid, sucrose, lactic acid, and trigonelline were identified in fermented coffees with the joint analysis of NMR and the loadings of PC1. Monte Carmelo coffees processed by the pulped method stood out sensorially showed a higher dominance rate for woody, herbaceous and fruity attributes. The SIAF positively impacts microbial behavior, resulting in coffees with a more intensified fruity attribute.


Assuntos
Café , Microbiota , Anaerobiose , Quimiometria , Fermentação
8.
J Sci Food Agric ; 102(14): 6687-6695, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35620803

RESUMO

BACKGROUND: After the harvest, green coffee beans are dried on the farm using several methods: the wet process, natural process, pulped natural process, or mechanical demucilaging. This study evaluated how the choice of a specific processing method influenced the volatile organic compounds of the coffee beans, before and after roasting, and the sensory characteristics of the beverage. Coffea arabica beans of two varieties (cv. Mundo Novo and cv. Catuai Vermelho) were subjected to these four processing methods on a single farm in the Cerrado area of Brazil. RESULTS: Analysis by gas chromatography-mass spectrometry headspace solid-phase microextraction identified 40 volatile organic compounds in green coffee beans and 37 in roasted beans. The main difference between post-harvest treatments was that naturally processed green beans of both varieties contained a different profile of alcohols, acids, and lactones. In medium-roasted beans, those differences were not observed. The coffee beverages had similar taste attributes but distinct flavor profiles. Some of the treatments resulted in specialty-grade coffee, whereas others did not. CONCLUSION: The choice of a specific post-harvest processing method influences the volatile compounds found in green beans, the final beverage's flavor profile, and the cupping score, which can have a significant impact on the profitability of coffee farms' operations. © 2022 Society of Chemical Industry.


Assuntos
Coffea , Compostos Orgânicos Voláteis , Coffea/química , Manipulação de Alimentos/métodos , Lactonas/análise , Sementes/química , Compostos Orgânicos Voláteis/química
9.
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
10.
Biodegradation ; 32(5): 551-562, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34046776

RESUMO

In this work, strains of Bacillus subtilis were inoculated in consortium with Rhodotorula mucilaginosa into spent soy oil as aiming to biological treatment and low-cost reuse. The microorganisms were previously isolated and selected for the lipolytic capacity of the alperujo residue generated during the processing of olive oil. For fermentation, bioassays containing Rhodotorula mucilaginosa isolated from alperujo and Candida rugosa CCMA 00371, both co-inoculated with Bacillus subtilis CCMA 0085 in medium containing (% w/v) 0.075 glucose and 0.375 (NH4)3 PO4 in 75 mL of water and 75 mL of spent soy oil. Despite the low biomass productivity, it has favorable characteristics to be used in animal feed supplementation. Spent soy oil was used as a carbon source proven by Bartha respirometer. The strains of R. mucilaginosa UFLA RAS 144 and B. subtilis CCMA 0085 are promising inoculants for oil degradation and can be applied in a waste treatment system.


Assuntos
Consórcios Microbianos , Óleo de Soja , Biodegradação Ambiental , Hidrólise , Rhodotorula , Saccharomycetales , Tecnologia
11.
J Therm Biol ; 97: 102897, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33863450

RESUMO

The objective of this study was to evaluate the effect of heat stress on meta-taxonomic and metabolic profiles of prokaryotes in beef cattle rumen. Six pure-breed Nellore heifers with ruminal cannulas were used in the study. Six treatments were tested in a 6 × 6 Latin Square with six periods of 21days. The treatments were evaluated in a 2 × 2 + 2 factorial arrangement, consisting of 4 combinations: two temperatures conditions (thermoneutral, TN: 24 °C; and heat stress, HS: 34 °C) and two dietary energy concentration [low-energy (37% non-fibrous carbohydrates - NFC, 12 Mcal of metabolizable energy per kg of dry matter) or high-energy concentration (50.5% NFC, 18.49 Mcal of metabolizable energy per kg of dry matter)] plus two additional treatments with animals maintained in TN conditions but with your intake restricted (TN-RI) to the same of the heifers in HS with the two dietary energy concentration. The meta-genome was sequenced by MiSeq Sequencing System platform, and the DNA sequences were analysed using Geneious 10.2.3 software. The metabolic profile was evaluated by liquid and gas chromatography. Animals under HS presented lower (P = 0.04) prokaryote richness than animals under TN conditions. The genera Flavonifractor (1.4%), Treponema (0.6%) and Ruminococcus (0.9%) showed the lowest (P < 0.04) and Carnobacterium (7.7%) the highest (P = 0.02) relative abundance when the animals were submitted to HS, in relation to animals in TN. A total of 49 different metabolites were identified in the ruminal samples. The concentration of isobutyric acid (4.32 mM) was highest in bovine rumen under HS conditions. Heat stress influenced the microbiota and concentration of some organic acids in beef cattle rumen. There was a reduction in the richness of rumen in cattle under heat stress, but the diversity of prokaryotes was not affected.


Assuntos
Ácidos Carboxílicos/metabolismo , Microbiota , Rúmen/metabolismo , Rúmen/microbiologia , Animais , Bactérias/genética , Bactérias/isolamento & purificação , Bovinos , Doenças dos Bovinos/microbiologia , Feminino , Transtornos de Estresse por Calor/microbiologia , Transtornos de Estresse por Calor/veterinária , Resposta ao Choque Térmico , Umidade , Methanobrevibacter/genética , Methanobrevibacter/isolamento & purificação , RNA Ribossômico 16S/genética , Temperatura
12.
J Environ Manage ; 278(Pt 2): 111541, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33129032

RESUMO

The coffee processing wastewater (CPWW) requires treatment before being disposed of in the environment or reused due to its high organic and inorganic composition and a low pH. The indigenous microbiota from CPWW is highly diverse and could be selected as inoculums in treatment waste plants. Considering the physico-chemical characteristics of wastewater coffee, we elaborate on steps to select the microbial consortium that showed positive impact via decreasing the pollutant parameters of this effluent. The effectiveness was confirmed using wastewater from different origins with different chemical characteristics. A bacterial consortium composed by Serratia marcescens CCMA 1010 and CCMA 1012, Corynebacterium flavescens CCMA 1006, and Acetobacter indonesiensis CCMA 1002 was selected as the inoculums-based phenotypic assays. The mixed inoculum showed a highly active population (11.18 log CFU mL-1), promoting an 85% decrease in biochemical oxygen demand and a 60% decrease in chemical oxygen demand. There was also an 80% reduction in phosphorus and nitrogen. The final pH changed from 6.0 to 7.5. Additionally, the eco-toxicity using Daphnia similis was reduced by more than 59%. The microbial inoculum was efficient in the biological treatment in CPWWs, demonstrating the efficiency and robustness of the selected strains, independent of the physico-chemical characteristics of wastewater.


Assuntos
Águas Residuárias , Poluentes Químicos da Água , Acetobacter , Animais , Análise da Demanda Biológica de Oxigênio , Café , Corynebacterium , Eliminação de Resíduos Líquidos
13.
J Sci Food Agric ; 101(10): 4409-4419, 2021 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-33421137

RESUMO

BACKGROUND: Fermented cocoa beans (Theobroma cacao L.) are a pivotal raw material for chocolate production. A cocktail yeast applied in the cocoa fermentation process can promote the formation of pleasant metabolites. Saccharomyces, Pichia and Hanseniaspora have been widely used in fermentation to improve the final product organoleptic profile, highlighting that fermentation is a critical point for chocolate flavour precursor production. This study aims to evaluate the impact of Pichia kluyveri and Saccharomyces cerevisiae strains as starter cultures on the fermentation for two cocoa hybrids, FA13 and CEPEC2002. RESULTS: During fermentation processes, volatile organic compounds (VOCs) and protein profiles were assessed. Chocolates produced were also assessed regarding the presence of VOCs. Eighty VOCs were identified using gas chromatography coupled to mass spectrometry analysis. Mass spectrometry provided the protein profile evolution during fermentation and showed that the profiles changed with inoculation type (spontaneous versus inoculated fermentation). Chocolate obtained from FA13 inoculated with S. cerevisiae strain contained a greater amount of organics acids, being categorised as sourer than chocolate produced by spontaneous fermentation of FA13. CEPEC2002 inoculated with S. cerevisiae strain in co-culture with P. kluyveri strain generated less sour and sweeter chocolate than spontaneous fermentation only. CONCLUSIONS: Chocolates from inoculated assays with starter cultures were more accepted by evaluators, highlighting that P. kluyveri and S. cerevisiae influence the composition of VOCs. Besides, protein profiles also changed throughout fermentation. Further investigation should be conducted to clarify protein degradation dynamics during inoculated fermentations to define which of the microbial cultures positively affect the chocolate sensory characteristics. © 2021 Society of Chemical Industry.


Assuntos
Cacau/microbiologia , Pichia/metabolismo , Saccharomyces cerevisiae/metabolismo , Cacau/química , Cacau/metabolismo , Chocolate/análise , Chocolate/microbiologia , Fermentação , Aromatizantes/química , Aromatizantes/metabolismo , Microbiologia de Alimentos , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Sementes/química , Sementes/metabolismo , Sementes/microbiologia , Paladar , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo
14.
J Sci Food Agric ; 101(6): 2570-2575, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33058186

RESUMO

BACKGROUND: The terrain slope and field altitude where the plant is cultivated influence the composition of coffee cherries. The aim of this study was to analyze the effects of different levels of altitude and terrain slope on the Coffea canephora cherries, as well as on the quality of the final beverage. C. canephora harvested in fields with 300 and 600 m altitude and with southeast- and northwest-facing slopes was evaluated. RESULTS: Lower pH values were observed for cherries cultivated at higher altitudes. The highest percentage of soluble solids (525.00 g kg-1 ) was found on northwest-facing slopes at 300 m. The highest values of phenolic compounds were observed at 600 m. Significant differences were found in the moisture of coffee cherries grown in different terrain slope and in the fiber content at different altitudes. The results do not enable us to conclude how the altitude and terrain slope influence the mineral content of cherries. Acidity, proteins, lipids, and carbohydrates were not influenced by altitude or terrain slope. The scores of cup quality were significantly affected by the altitude but not by the terrain slope. Coffees from cherries harvested in fields with 600 m altitude obtained the higher scores. CONCLUSION: Results show that altitude and terrain slope influence some compounds of coffee fruits, whereas others remain unaffected. The findings are important because, during coffee fruits processing, these compounds are used to produce others that will have an influence on the bean and coffee beverage quality. © 2020 Society of Chemical Industry.


Assuntos
Coffea/crescimento & desenvolvimento , Café/metabolismo , Sementes/química , Altitude , Coffea/química , Café/química , Humanos , Sementes/crescimento & desenvolvimento , Paladar
15.
World J Microbiol Biotechnol ; 37(3): 51, 2021 Feb 17.
Artigo em Inglês | MEDLINE | ID: mdl-33594606

RESUMO

This study aimed to assess the microbial diversity in Coffea canephora grown in four different environments of Espirito Santo state, Brazil. Coffee cherries of two different altitudes (300 and 600 m) and two terrain aspects (Southeast-facing and Northwest-facing slopes) were processed by the dry method. Samples were collected during the drying/fermentation process. Microorganisms were counted, isolated, and identified by MALDI-TOF, followed by sequencing of the ribosomal region. Sugars and organic acids were quantified by HPLC and volatile compounds of the roasted coffees were evaluated by GC-MS. Bacteria population presented a significant number of isolates as well as higher counts during the drying/fermentation process with respect to the population of yeasts. The principal genera of microorganisms found were Bacillus, Pichia, Candida, and Meyerozyma. Meyerozyma guilliermondii was the most frequent yeast in all environments. On the other hand, Pichia kluyveri was found only in coffee cherries from the 600 m altitude. The highest concentration of acetic and succinic acids observed was 6.06 mg/g and 0.84 mg/g, respectively. Sucrose concentrations ranged from 0.68 to 5.30 mg/g, fructose from 1.30 to 4.60 mg/g, and glucose from 0.24 to 1.25 mg/g. Thirty-six volatile compounds, belonging to the groups of pyrazines, alcohols, aldehydes, ketones, and furans were identified in roasted coffee, with differences between altitude and terrain aspects. Information about microbial diversity is crucial to better understand the coffee quality and distinct characteristics of coffee produced in different environments.


Assuntos
Coffea/química , Coffea/microbiologia , Dessecação/métodos , Manipulação de Alimentos/métodos , Álcoois , Bactérias/classificação , Brasil , Café/química , Café/microbiologia , Fermentação , Fungos/classificação , Cromatografia Gasosa-Espectrometria de Massas
16.
Microb Pathog ; 140: 103969, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31918000

RESUMO

The consumption of probiotics has increased due to the reported health benefits, mainly in preventing or treating gastrointestinal pathology. This study investigated the antimicrobial capacity of yeasts, Saccharomyces cerevisiae and Pichia kluyveri, previously isolated from fermented foods (indigenous beverage, kefir and cocoa) against the adhesion of foodborne pathogens to Caco-2 cells. Co-aggregation of yeasts with pathogens and were evaluated by quantitative analysis and using scanning electron and laser confocal microscopies. All yeasts strains were able to co-aggregate with the tested pathogens, however, this activity was strain-dependent. The inhibition tests showed that the adhesion of Escherichia coli EPEC, Listeria monocytogenes and Salmonella Enteritidis to Caco-2 was reduced by all the yeasts studied. Most of the evaluated yeasts showed inhibition rates equal to or greater than the commercial probiotic Saccharomyces boulardii. The yeasts were able to reduce up to 50% of the bacterial infection, as observed for CCMA0615 towards EPEC in exclusion assay; CCMA0731, CCMA0732 and CCMA0615 towards L. monocytogenes in exclusion and competition assays; and CCMA0731 in exclusion and CCMA0731, CCMA0732, CCMA0615 in competition assay towards S. Enteritidis. No antimicrobial compounds were produced by the yeasts, showing that competition for nutrients and/or receptors in the intestinal mucosa was the mechanism to bacterial inhibition.


Assuntos
Antibiose , Alimentos Fermentados/microbiologia , Pichia/fisiologia , Saccharomyces cerevisiae/fisiologia , Aderência Bacteriana , Brasil , Células CACO-2 , Escherichia coli/fisiologia , Microbiologia de Alimentos , Humanos , Listeria monocytogenes/fisiologia , Pichia/genética , Pichia/isolamento & purificação , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/isolamento & purificação , Salmonella enteritidis/fisiologia
17.
World J Microbiol Biotechnol ; 36(12): 186, 2020 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-33219454

RESUMO

The use of starter cultures during food fermentation aims to standardize the process and to obtain a higher quality product. The objectives were to study mesophilic bacteria (MB) and lactic acid bacteria (LAB) isolated from wet coffee processing and evaluate their performance in a pulped coffee medium. Eighty-six bacteria isolates (59 MB and 27 LAB) were assessed for pectinolytic activity, metabolite production, and pH value decrease in coffee-based culture (CPM). Seven bacteria strains (3 MB and 4 LAB) were selected and used as starter cultures in the wet fermentation of pulped coffee. The MB and LAB populations varied from 4.48 to 8.43 log CFU g-1 for MB and 3.54 to 8.72 log CFU g-1 for LAB during fermentation. Organic acid concentration (ranged from 0.01 to 0.53 for succinic acid; 0.71 to 8.14 for lactic acid and 0.06 to 0.29 for acetic acid), and volatile compounds (44 compounds were detected in green beans and 98 in roasted beans) were evaluated during fermentation. The most abundant compounds found in roasted beans belong to furans [15], ketones and esters [14], pyridines [13], and pyrazines [12]). Leuconostoc mesenteroides CCMA 1105 and Lactobacillus plantarum CCMA 1065 presented volatile compounds important for coffee aroma. Isovaleric acid; 2,3-butanediol; phenethyl alcohol; ß-linalool; ethyl linoleate; and ethyl 2-hydroxypropanoate could improve cupping qualities.


Assuntos
Bactérias/crescimento & desenvolvimento , Bactérias/metabolismo , Café/metabolismo , Café/microbiologia , Microbiologia de Alimentos , Fermentação , Manipulação de Alimentos/métodos , Odorantes/análise , Paladar
18.
J Sci Food Agric ; 99(13): 5638-5645, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31124153

RESUMO

BACKGROUND: The aim of this study was to evaluate the performance of yeasts Saccharomyces cerevisiae CCMA 0200 and Torulaspora delbrueckii CCMA 0684 in Mundo Novo and Catuaí varieties processed by the wet method and the impact on sensory quality and compounds profile. The microbiota was evaluated by surface plating, and the compounds were evaluated by high-performance liquid chromatography and gas chromatography-mass spectrometry. Sensorial analysis was performed using the cupping test (Specialty Coffee Association). RESULTS: T. delbrueckii CCMA 0684 was better adapted to the process and remained for up to 72 h of drying. Eighteen volatile compounds were detected in green coffee and 75 in roasted coffee. 2-Furanmethanol propanoate and 2-ethyl-3,5-dimethylpyrazine were identified only in the inoculated treatments, and these are important contributors to the coffee aroma. All treatments received scores greater than 80 in the sensory analysis. CONCLUSION: T. delbrueckii CCMA 0684 presented better results in relation to the sensorial analysis and is preferable for the varieties and processing method studied. The use of starter cultures is a viable method with which to obtain high-quality coffees with a distinct flavor and thus add to value to the product. © 2019 Society of Chemical Industry.


Assuntos
Coffea/química , Saccharomyces cerevisiae/metabolismo , Cromatografia Líquida de Alta Pressão , Coffea/microbiologia , Café/química , Fermentação , Aromatizantes/química , Aromatizantes/metabolismo , Cromatografia Gasosa-Espectrometria de Massas , Humanos , Microbiota , Odorantes/análise , Controle de Qualidade , Paladar , Compostos Orgânicos Voláteis/química , Compostos Orgânicos Voláteis/metabolismo
19.
J Sci Food Agric ; 99(5): 2267-2274, 2019 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-30328118

RESUMO

BACKGROUND: To reduce postharvest losses, substandard fruit and agricultural surpluses can productively be used as raw material for vinegar production. The present study aimed to prepare vinegars from surpluses of physalis (Physalis pubescens L.) and red pitahaya (Hylocereus monacanthus) and then evaluate their sensorial characteristics, antimicrobial activities, total phenolic content (TPC) and total antioxidant capacity by the 2,2-diphenyl-1-picrylhydrazyl (DPPH) and 2,2'-azino-bis(3-ethylbenzo thiazoline-6-sulfonic acid) methods. RESULTS: Two vinegars were produced by submerged fermentation using physalis and red pitahaya fruits surpluses. Physalis and red pitahaya vinegars had 47 and 45 g L-1 acetic acid, respectively, and both vinegars contained approximately 1 g L-1 ethanol. Both vinegars displayed antimicrobial activity against Escherichia coli, Listeria monocytogenes, Staphylococcus aureus and Salmonella enteritidis. The TPC of physalis and red pitahaya vinegar was 0.5638 and 0.3656 g L-1 g gallic acid L-1 for physalis and red pitahaya, respectively. A similar antioxidant activity was detected in both the wines and vinegars. The sensorial analysis revealed that the consumers 'like moderately' each vinegar, and citric aroma was noted in the physalis vinegar. CONCLUSION: In the present study, vinegars with sensorial characteristics approved by consumers were developed using fruit surpluses, adding value through a new product making use of a simple methodology that is both inexpensive and demonstrates a good yield. © 2018 Society of Chemical Industry.


Assuntos
Ácido Acético/metabolismo , Bebidas Alcoólicas/análise , Antibacterianos/química , Antioxidantes/química , Cactaceae/química , Physalis/química , Ácido Acético/análise , Antibacterianos/metabolismo , Antibacterianos/farmacologia , Antioxidantes/metabolismo , Antioxidantes/farmacologia , Cactaceae/metabolismo , Cactaceae/microbiologia , Fermentação , Humanos , Fenóis/química , Fenóis/metabolismo , Fenóis/farmacologia , Physalis/metabolismo , Physalis/microbiologia , Paladar
20.
Environ Monit Assess ; 191(5): 284, 2019 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-30997565

RESUMO

This work evaluated the efficiency of bacterial bio-augmentation to the biological treatment of coffee processing wastewater (CPWW) in a pilot wastewater treatment plant (WTP). Biochemical oxygen demand (BOD) and chemical oxygen demand (COD) values were the basis for the treatment efficiency. Serratia marcescens CCMA 1010 and CCMA 1013, Corynebacterium flavescens CCMA 1006 and Acetobacter indonesiensis CCMA 1002 were previously selected. The microbial cocktail was inoculated and persisted in CPWW during all treatments. The richness of wild species was a little altered over time and up to nine species were found in each sampled season. The microbiota composition presented variation of a total of 13 species, despite the inoculation of the microbial inoculum. The biodegradability index of effluent, close to 0.5, was favourable to biological treatment. The pollution parameters of CPWW were decreased in function of the variation of community composition and microbial activity. The greatest reduction of BOD (~ 33%) and COD (~ 25%) was observed between 72 h and 8 days of the biological treatment. The CPWW toxicity in Allium cepa seeds was lower by up to 60%, and the germination index (GI) exceeded 100% in the treated CPWW. The results of the CPWW biological treatment by bio-augmentation from native micro-organisms in the pilot-scale WTP indicated the greatest efficiency relating to the spontaneous biological treatment of CPWW. After this treatment, the discharge of effluent in the environment would not have toxic effects on the plants.


Assuntos
Biodegradação Ambiental , Café , Monitoramento Ambiental/métodos , Águas Residuárias/química , Bactérias/metabolismo , Análise da Demanda Biológica de Oxigênio , Projetos Piloto , Eliminação de Resíduos Líquidos/métodos
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