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1.
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
2.
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
3.
Food Res Int ; 159: 111605, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35940800

RESUMO

Altitude changes the coffee fruits and beans composition before and after harvesting. We aimed to evaluate the effect of altitude on the microbial community structure associated with pulped coffee fruits under self-induced anaerobic fermentation (SIAF) and their acids, volatiles, and antioxidants biochemical profiles. The most abundant bacterial genera were Gluconobacter (800 m), Weissella (1,000 m), and Leclercia (1,200 and 1,400 m). Yeasts dominated the pulped natural fermentations within the fungal species, containing high abundances of Cystofilobasidium infirmominiatum, Wickerhamomyces anomalus, and Meyerozyma caribbica. Citric, alcohols, and caffeine were the most dominant compounds in SIAF among acids, volatiles, chemical groups, and antioxidants. High altitude coffees favor alcohols, aldehydes, and esters groups, while low altitude coffees favor phenols.


Assuntos
Café , Microbiota , Álcoois , Altitude , Antioxidantes , Café/química
4.
Int J Food Microbiol ; 379: 109839, 2022 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-35868147

RESUMO

The storage of microorganisms in liquid form is the main drawback of commercializing epiphytic coffee yeasts. This work aimed to evaluate the fermentative performance of microencapsulated yeasts by spray drying in a coffee peel and pulp media (CPM). The yeasts, Saccharomyces cerevisiae CCMA 0543, Torulaspora delbrueckii CCMA 0684, and Meyerozyma caribbica CCMA 1738, were microencapsulated using maltodextrin DE10 (MD), high maltose (MA), and whey powder (WP) as wall materials. A Central Composite Rotational Design (CCRD) was used to investigate the effect of operating parameters on the microcapsules' cell viability, drying yield, and water activity. Yeasts reached cell viability and drying yields above 90 and 50 %, respectively. WP maintained the cell viability of the three yeasts over 90 days of storage at room temperature (25 °C) and was selected as a wall material for the three yeasts. M. caribbica showed to be more sensitive to spray drying and less resistant to storage. Some differences were found in the fermentation of the CPM medium, but the microencapsulated yeasts maintained their biotechnological characteristics. Therefore, the microencapsulation of epiphytic coffee yeasts by spray drying was promising to be used in the coffee fermentation process.


Assuntos
Café , Torulaspora , Fermentação , Saccharomyces cerevisiae , Secagem por Atomização , Proteínas do Soro do Leite
5.
Braz J Microbiol ; 53(3): 1565-1576, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35676493

RESUMO

The objective of this work was to evaluate the microencapsulation feasibility of Saccharomyces cerevisiae CCMA 0543 and Torulaspora delbrueckii CCMA 0684 in three different compositions of wall material by spray-dryer. The yeasts (109 CFU mL-1) were microencapsulated separately using maltodextrin (15%), maltodextrin (15%) with sucrose (2%), or maltose (2%) as wall material. The viability was evaluated for 6 months at two different temperatures (7 and 25 °C). The yield, cell viability after spray drying, and characterization of the microcapsules were performed. Results indicate that cell viability ranged between 94.06 and 97.97%. After 6 months, both yeasts stored at 7 °C and 25 °C presented 107 and 102 CFU mL-1, respectively. Regarding Fourier-transform infrared spectroscopy analysis, all microencapsulated yeasts presented typical spectra footprints of maltodextrin. After 6 months of storage, S. cerevisiae CCMA 0543 obtained a 10.8% increase in cell viability using maltodextrin with maltose as wall material compared to maltodextrin and maltodextrin with sucrose. However, T. delbrueckii CCMA 0684 obtained a 13.5% increase in cell viability using only maltodextrin. The study showed that maltodextrin as a wall material was efficient in the microencapsulation of yeasts. It is possible to assume that maltose incorporation increased the cell viability of S. cerevisiae CCMA 0543 during storage.


Assuntos
Torulaspora , Café/química , Café/metabolismo , Fermentação , Maltose/metabolismo , Saccharomyces cerevisiae/metabolismo , Secagem por Atomização , Sacarose/metabolismo , Torulaspora/metabolismo
6.
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
7.
Int J Food Microbiol ; 369: 109627, 2022 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-35305516

RESUMO

Wet coffee fermentation is widely used in coffee-producing regions such as Colombia and Hawaii, but it is not widespread in Brazil. This study aimed to evaluate inoculating the lactic acid bacteria Leuconostoc mesenteroides CCMA1105 and Lactiplantibacillus plantarum CCMA 1065 and the yeasts Saccharomyces cerevisiae CCMA0543 and Torulaspora delbrueckii CCMA0684 as starter cultures on wet coffee fermentation using the SIAF method (self-induced anaerobiosis fermentation). The microbial activity resulted in high consumption of the carbohydrates glucose (98.6%), fructose (97.6%), and sucrose (100%), in addition to the production of lactic and acetic acids, impacting the final quality of the beverage. A total of 108 volatile compounds belonging to 17 classes were identified in the green and roasted coffee samples, including 2,3-butanediol produced by lactic acid bacteria, contributing to coffee's aromatic profile. The final scores for the coffees from the different fermentations ranged from 79.0 to 83.25. The inoculated fermentations were classified as specialty according to the Specialty Coffee Association. Therefore, whole coffee fruit processed via wet using SIAF method and yeast and lactic acid bacteria starter is an alternative for improving wet fermented coffee quality and obtaining coffee beverages with a different sensory profile.


Assuntos
Coffea , Lactobacillales , Torulaspora , Coffea/microbiologia , Café/microbiologia , Fermentação , Leveduras
8.
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
9.
Food Res Int ; 150(Pt A): 110755, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34865773

RESUMO

Selected yeasts for coffee fermentation are correlated with changes in chemical compounds and beverage sensory characteristics. This work aimed to evaluate the chemical and sensory modifications of coffee fermented with one yeast (Saccharomyces cerevisiae CCMA 0543, Candida parapsilosis CCMA 0544, or Torulaspora delbrueckii CCMA 0684) and in co-inoculation (from two to two and the three together) by dry processing. Real-time PCR analyzes, total phenolic content and antioxidant activity (DPPH, ABTS, and FRAP), liquid and gas chromatography, and sensory analysis were performed. Caparaó coffees showed a higher C. parapsilosis (6.14 Log cell.g-1) population followed by S. cerevisiae (5.85 Log cell.g-1) and T. delbrueckii (4.64 Log cell.g-1). The total phenolic content has a strong and positive correlation with the fermentation time and the roasted beans and a moderate and positive correlation with DPPH, FRAP, and ABTS. Coffee inoculated with T. delbrueckii reduced caffeine concentration during the fermentation process. In co-cultivation, the trigonelline concentration showed the most significant decrease (around 4 mg.g-1) when inoculated with S. cerevisiae and T. delbrueckii. Detection of some organic acids and volatile compounds during fermentation may indicate that the starter cultures used different metabolic routes. All co-inoculation treatments presented the best sensory scores (>86 points). In the inoculated fermentation, fruity, citric, molasses, freshness, and wine notes appeared. The co-inoculated treatment with S. cerevisiae CCMA 0543, C. parapsilosis CCMA 0544, and T. delbrueckii CCMA 0684 was the best, considering the diversity of sensory notes descriptors and the final concentration of organic acids.


Assuntos
Torulaspora , Vinho , Café , Fermentação , Saccharomyces cerevisiae , Vinho/análise
10.
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
11.
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
12.
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
13.
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
14.
J Food Sci ; 86(3): 740-748, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33580510

RESUMO

Kombucha is a black tea-based, non-alcoholic beverage fermented by yeast and bacteria are known for its refreshing scent and taste and presents biological characteristics, namely antioxidant, antimicrobial and anti-inflammatory activity. The present study compared traditional kombucha prepared with black tea and green tea to kombuchas produced with several alternative substrates, including white tea, chrysanthemum, honeysuckle, and mint infusions. Throughout the fermentation process, liquid and gas chromatography analyzed sugars, ethanol, organic acids, and volatile compounds. Sugar consumption was substrate-dependent, with mint kombucha having the highest amount of residual sugar and honeysuckle having the lowest. Forty-six volatile organic compounds were detected, including alcohols, esters, acids, aldehydes, ketones, and other compounds. Twenty-two compounds were produced during the fermentation and identified in all kombuchas; some of these compounds represented fruity and floral aromas. Another 24 compounds were substrate specific. Notably, the herb-based kombuchas (chrysanthemum, honeysuckle, and mint) contained several compounds absent in the tea-based kombuchas and are associated with minty, cooling, and refreshing aromas. Mint and green tea kombucha attained the highest and lowest overall sensorial acceptance ratings, respectively. This study demonstrated herbal substrates' suitability to prepare kombucha gastronomically with volatile compound and flavor profiles distinct from tea-based kombuchas. PRACTICAL APPLICATION: The kombucha beverage is a low-caloric functional drink that is increasingly popular around the world. While it is traditionally produced with black or green tea, this paper explores its production based on other herbal and floral infusions. The kombucha analogs presented in this paper can provide consumers with healthy alternatives for sugary soft drinks while also offering a broader range of flavors.


Assuntos
Chá de Kombucha/análise , Chás de Ervas/análise , Anti-Infecciosos/análise , Anti-Inflamatórios/análise , Antioxidantes/análise , Bebidas/análise , Camellia sinensis/química , Etanol/análise , Fermentação , Sensação , Açúcares/análise , Paladar , Chá/química , Compostos Orgânicos Voláteis/análise
15.
Food Res Int ; 139: 109921, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33509488

RESUMO

Fermenting in bioreactors can improve coffee quality, standardize the fermentation process, and generate specialty coffees. This work aimed to evaluate novel stainless steel bioreactors with inoculated and non-inoculated coffees processed via natural and pulped natural. Yeast and bacteria populations were evaluated and grown on Yeast Extract Peptone Glucose; De Man, Rogosa, and Sharpe; and Nutrient agar media. Volatile compounds from roasted beans were analyzed in a Gas Chromatography-Mass Spectrometry equipment, and the sensory perception was evaluated through a cup test. The mesophilic bacteria population was statistically significant in pulped natural coffee compared to yeast and lactic acid bacteria. Furans had the highest concentration among the chemical groups. Beverage inoculated with CCMA 0535 presented the highest SCA score. Prune, peach, and floral attributes were only perceived in Nat CCMA 0535. The sensory perception indicated that the inoculated yeasts modified the flavor attributes, enhanced the quality, and increase their SCA scores.


Assuntos
Café , Fermento Seco , Fermentação , Humanos , Aço Inoxidável , Leveduras
16.
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
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.
Microbiol Res ; 241: 126585, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-32919224

RESUMO

Garlic (Allium sativum L.) is one of the crops whose economic importance has increased considerably in recent years in Brazil. The use of plant growth-promoting bacteria (PGPB) is a useful alternative for reducing the cost of agricultural inputs and, consequently, for increasing productivity. Therefore, the main objective of this work was to isolate and evaluate potential growth promoters in plants and plant pathogenic fungi growth inhibitors using endophytic bacteria from garlic roots and bacteria from the Agricultural Microbiology Culture Collection at the Federal University of Lavras. Besides verifying improvements in the growth and physiology of garlic meristems grown in vitro under the action of PGPB. Forty-eight endophytic bacteria were identified using matrix-assisted laser desorption/ionization-time of flight mass spectrometry based on the protein profile of each isolate. Four isolates were chosen according to their ability to fix nitrogen, to produce auxin and solubilize phosphate. The cultivation of garlic meristems in tissue culture with these bacteria was established at a population level of 106 CFU/mL. The evaluated criteria were: (1) the colonization capacity of the bacteria inside the garlic plants determined through scanning electron microscopy; (2) the chlorophyll content; and (3) the growth of garlic plants in vitro post-PGPB inoculation. Volatiles emitted by those isolates inhibited fungi growth. The inoculation of garlic meristems with Enterobacter cloacae and Burkholderia cepacia promoted an improvement in the growth and physiological attributes of garlic, indicating the feasibility of their application as plant growth promoters for commercial cultivation.


Assuntos
Bactérias/metabolismo , Alho/microbiologia , Meristema/crescimento & desenvolvimento , Desenvolvimento Vegetal/fisiologia , Raízes de Plantas/crescimento & desenvolvimento , Antifúngicos/metabolismo , Bactérias/isolamento & purificação , Brasil , Burkholderia cepacia/metabolismo , Clorofila/análise , Endófitos/metabolismo , Enterobacter cloacae/metabolismo , Ácidos Indolacéticos/metabolismo , Microscopia Eletrônica de Varredura , Fixação de Nitrogênio/fisiologia , Raízes de Plantas/microbiologia
19.
Food Res Int ; 136: 109482, 2020 10.
Artigo em Inglês | MEDLINE | ID: mdl-32846564

RESUMO

Fermentation is one of the post-harvest steps that influence coffee quality. This work evaluated the effect of Saccharomyces cerevisiae (CCMA 0543) and Torulaspora delbrueckii (CCMA 0684) inoculation on the quality of natural and pulped natural processed coffee in different producing regions. Yeast populations were assessed by the real-time polymerase chain reaction. Volatile and nonvolatile compounds were evaluated by gas chromatography-mass spectrometry and high-performance liquid chromatography, respectively. S. cerevisiae was predominant during spontaneous (average of 4 log cells/g) and inoculated (average of 7 log cells/g) fermentations in both processes. T. delbrueckii showed a similar population (3.79 log cells/g) in all assays. Glucose and fructose were the most detected sugars in coffee beans. Succinic acid was found at the end of the fermentative process. The lactic acid concentration was inversely proportional to ethanol concentration. Pyrrole and furan, which are volatile groups, allowed to differentiate the coffee processing methods. Yeast inoculation modified the sensorial profile and increased the coffee beverage scores by up to 5 points. S. cerevisiae inoculation was most suitable for pulped natural coffee, and T. delbrueckii inoculation showed the best performance in natural coffee.


Assuntos
Torulaspora , Fermento Seco , Café , Fermentação , Saccharomyces cerevisiae
20.
Food Res Int ; 129: 108872, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-32036899

RESUMO

The objective of this work was to evaluate the influence of different altitudes on the epiphytic microbiota of coffee beans and on sensorial and chemical quality of coffees grown at 800, 1000, 1200, and 1400 m in Serra do Caparaó, Espírito Santo, Brazil. For microbiological analysis, the population counts of mesophilic bacteria, lactic acid bacteria (LAB), and yeasts were performed from the surface plating. The isolates were grouped and identified from the Matrix Assisted Laser Desorption Ionization Time-of-Flight Mass Spectrometry (MALDI-TOF MS) and sequencing of the ribosomal region was used. The chemical composition of the green grains was evaluated by Raman spectroscopy, and the sensory analysis of the roasted grains was performed using temporal dominance of sensations (TDS). During fermentation, there was a decrease in the LAB in pulped coffee from 800 and 1000 m altitude, while an increase was observed at 1200 and 1400 m. In natural coffee, there was an increase of LAB population at all altitudes. The highest diversity of mesophilic bacteria and yeast were identified in natural 1400 m and 1000 m, respectively. However pulped coffee treatments it was at 1200 m and 800 m. The chlorogenic acid and fatty acids in the green bean changed with altitude variation and processing. The floral attribute was detected only at altitude 1400 m. Caramel, chocolate and almond attributes were most frequently detected in coffees at different altitudes and processing. Therefore, pulped coffee processing was most suitable at low altitude while at high altitudes, both processes can be conducted to obtain a beverage with unusual sensory profile.


Assuntos
Altitude , Bactérias , Coffea/crescimento & desenvolvimento , Café/normas , Leveduras , Agricultura , Café/química , Café/microbiologia
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