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1.
Foods ; 13(6)2024 Mar 09.
Artigo em Inglês | MEDLINE | ID: mdl-38540829

RESUMO

The metataxonomic diversity and microbial composition of microorganisms during the coffee fermentation process as well as their relationship with coffee quality were determined across 20 farms in the department of Cesar, Colombia, by sampling coffee fruits from Coffea arabica; Var. Castillo General®, Var. Colombia, and Var. Cenicafé 1. In each farm, the fruits were processed and the fermentation process took place between 10 and 42 h following this. Three samples of mucilage and washed coffee seeds were collected per farm during the fermentation process. The microorganisms present in the mucilage were identified using metataxonomic methods by amplifying the 16S rRNA gene for bacteria and ITS for fungi. The microorganisms' morphotypes were isolated and identified. The analysis of bacteria allowed for the identification of the following genera: Gluconobacter, Leuconostoc, Acetobacter, Frateuria, Pantoea, Pseudomonas, Tatumella, and Weisella, as well as unclassified enterobacteria; the Lactobacillacea and Secundilactobacillus families were only identified in the Var. Cenicafé 1. For fungi, the top 11 genera and families found included Hanseniaspora, Candida, Meyerozyma, Wickerhamomyces, Pichia, f-Saccharomycodaceae, f-Nectriciae, unclassified fungi, and Saccharomycetaceae, which were only found in Cenicafé 1. A total of 92% of the coffee samples obtained scored between 80.1 and 84.9, indicating "Very Good" coffee (Specialty Coffee Association (SCA) scale). Farms with the longest fermentation times showed better coffee attributes related to acidity, fragrance, and aroma. During coffee fermentation, there is a central microbiome. The differences between the microorganisms' genera could be influenced by the coffee variety, while the specific conditions of each farm (i.e., altitude and temperature) and its fermentation processes could determine the proportions of and interactions between the microbial groups that favor the sensory characteristics responsible for coffee cup quality.

2.
J Chem Ecol ; 46(9): 881-890, 2020 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-32803512

RESUMO

The coffee berry borer (CBB) is one of the main coffee pests in the world including Colombia. This pest is difficult to manage because of its cryptic habits and the continuous availability of coffee fruits. Among the new management strategies being tested is the use of volatile compounds as insect repellents. In this work, the behavioral response of female adult CBBs to terpenes previously identified in the CBB-repellent plant species Lantana camara was evaluated. α-Terpinene, (R)-limonene, farnesene and ß-caryophyllene terpenes were tested via a Y-tube olfactometer in which ripe coffee fruits were accompanied by terpenes at concentrations between 25 and 200 ppm. Only ß-caryophyllene induced a significant and consistent CBB repellent effect at all tested doses. The protective effect of microencapsulated ß-caryophyllene was then determined under laboratory conditions by incorporating the terpene in a colloidosome-gel system at 2.8 × 105 ng/h in the middle of coffee fruits with adult CBBs. The coffee fruits in turn presented a decrease in fruit infestation. Furthermore, the protection of coffee fruits when ß-caryophyllene gels were hung in coffee trees was evaluated in the field; infestations were artificially induced by the use of raisins (CBB-infested old coffee fruits) placed on the ground. Compared with unprotected trees, the trees treated with caryophyllene gels exhibited a 33 to 45% lower degree of infestation. Taken together, the results show that ß-caryophyllene is a promising compound for an integrated pest management (IPM) program in commercial coffee plantations.


Assuntos
Coffea/parasitologia , Besouros/efeitos dos fármacos , Repelentes de Insetos/farmacologia , Controle de Pragas/métodos , Terpenos/farmacologia , Compostos Orgânicos Voláteis/farmacologia , Animais , Comportamento Animal/efeitos dos fármacos , Feminino , Frutas/parasitologia , Repelentes de Insetos/isolamento & purificação , Lantana/química , Sementes/parasitologia , Terpenos/isolamento & purificação , Compostos Orgânicos Voláteis/isolamento & purificação
3.
Vitae (Medellín) ; 24(2): 132-145, 2017. Ilustraciones
Artigo em Inglês | LILACS, COLNAL | ID: biblio-994668

RESUMO

Background: Tea (Camellia sinensis) is the most highly consumed beverage in the world in addition to water. The most common way of preparation is by immersing the tea bag in hot or cold water. In Colombia, it is a recent trend and the market is growing continuously. Objectives: The objective of this study is to compare the antioxidant characteristics of four brands of green tea sold in Colombia at room and hot-temperature in relation to the preparation conditions. Methods: Four commercial brands of green tea (Oriental®, Lipton®, Hindú®, Jaibel®) were used in an aqueous extraction at two temperatures: Cold tea extract (25°C) and hot tea extract (80°C). Total polyphenol concentration (TPC) was determined by Folin-Ciocalteu method; Total flavonoid content (TFC) was determined by spectrophotometric method and the antioxidant capacity was determined by two methods: DPPH radical capture assay, and the oxygen radical absorbance capacity (ORAC) assay. Finally, a method to quantify the catechins of the tea extracts, high performance liquid chromatography (HPLC) was applied. Results: The TPC vary between: 2.53 ­ 14.63 mg GAE/ g sample for cold tea extract and 29.34 - 55.06 mg GAE/g sample for hot tea extract. The TFC vary between: 2.67 ­ 7.08 mg CE/g per sample for the cold tea extract and 5.43­ 8.41 mg CE/ g sample for hot tea extract. A similar profile assays: for cold tea extract: 22.36 ­ 41.29 mg TE /g sample for DPPH and 22.95 ­ 46.25 mg TE/g sample for ORAC. Similarly, for hot tea extract the following ranges were: 38.50 ­ 110.01 mg TE/g sample for DPPH and 23.40- 113.60 mg TE/g sample for ORAC. In general, the values obtained in each assay for each brand were as follows: Oriental®> Lipton®> Hindú®> Jaibel®. The chromatographic profiles showed the presence of ten compounds. Conclusions: These results confirm that the aqueous extraction of green tea at 80°C leads to the formation of infusions made up of compounds with higher antioxidant capacity in comparison with extractions at room temperature.


Antecedentes: El té (Camellia sinensis) es la bebida más consumida en el mundo, además del agua. La forma más común de preparación es sumergiendo la bolsa de té en agua caliente o fría. En Colombia, es una tendencia reciente y el mercado está creciendo. Objetivos: El objetivo de este estudio es comparar las características antioxidantes de cuatro marcas de té verde vendidas en Colombia en relación con las condiciones de preparación. Métodos: Se utilizaron cuatro marcas comerciales de té verde (Oriental®, Lipton®, Hindú®, Jaibel®) mediante extracción acuosa a dos temperaturas: extracto de té frío (25°C) y extracto de té caliente (80°C). La concentración total de polifenoles (TPC) se determinó mediante el método de Folin-Ciocalteu; el contenido total de flavonoides (TFC) se determinó mediante método espectrofotométrico y la capacidad antioxidante se determinó mediante dos métodos: ensayo de captura del radical DPPH y ensayo de capacidad de absorción de radicales de oxígeno (ORAC). Finalmente, para cuantificar las catequínas de los extractos de té se aplicó cromatografía líquida de alta resolución (HPLC). Resultados: Los valores para TPC varían entre 2,53 -14,63 mg GAE/g extracto de té frío y entre 29,34 - 55,06 mg GAE/g extracto de té caliente. Los valores para TFC varían entre 2,67 - 7,08 mg de CE/g extracto de té frío y entre 5,43 - 8,41 mg de CE/g extracto de té caliente. Se observó un perfil similar en la capacidad antioxidante mediante ambos ensayos, extracto de té frío: 22,36 - 41,29 mg TE/g por DPPH y 22,95 - 46,25 mg TE/g por ORAC, extracto de té caliente: 38,50 - 110,01 mg TE/g por DPPH y 23,40- 113,60 mg TE/g por ORAC. En general, los valores obtenidos en cada ensayo respecto a cada marca se comportaron así: Oriental®> Lipton®> Hindú®> Jaibel®. Los perfiles cromatográficos mostraron la presencia de 10 compuestos. Conclusiones: Estos resultados confirman que la extracción acuosa de té verde a 80°C conduce a la formación de infusiones ricas en compuestos con capacidad antioxidante en comparación con extracciones a temperatura ambiente.


Assuntos
Humanos , Chá , Antioxidantes , Temperatura Baixa , Temperatura Alta
4.
Rev. colomb. quím. (Bogotá) ; 45(3): 12-21, Sep.-Dec. 2016. ilus, map
Artigo em Inglês | LILACS | ID: biblio-960188

RESUMO

Simultaneous Distillation-Solvent Extraction (SDE) and Headspace Solid Phase Micro-extraction (HS-SPME), coupled to Gas Chromatography-Mass Spectrometry (GC-MS), for recovery of volatiles from lulo pulp (Solanum quitoense) were compared. A completely randomized SDE/GC-MS design was applied to establish differences between the areas obtained with different solvents, whereas a two-way HS-SPME/GC-MS indicated the most appropriate extraction conditions of volatiles, having the type of fiber and the adsorption temperature as factors. SDE/GC-MS mainly promoted the extraction of hydrocarbons, aldehydes, and esters; whereas esters and aldehydes had higher areas using HS-SPME/GC-MS. Furthermore, the variance analysis showed a significant interaction among the type of fiber, the adsorption temperature, and the functional groups.


Se compararon los métodos de extracción y destilación simultánea (SDE) y microextracción en fase sólida con espacio de cabeza (HS-SPME), acoplados a cromatografía de gases con detector de espectrometría de masas (GC-MS), para la recuperación de volátiles a partir de pulpa de lulo (Solanum quitoense). Se realizó un diseño completamente al azar aplicado al tipo de solvente para SDE/GC-MS, mientras que para HS-SPME/GC-MS se ejecutó un diseño a dos vías, teniendo como factores el tipo de fibra y la temperatura de adsorción. En el primer caso se obtuvieron principalmente hidrocarburos, aldehídos y ésteres; en el segundo, se recuperaron ésteres y aldehídos. El análisis de varianza mostró una interacción significativa entre el tipo de fibra, la temperatura de adsorción y los grupos funcionales.


Foram comparados os métodos de extração e destilação simultânea (SDE) e microextração em fase sólida com espaço de cabeça (HS-SPME), acopladas à cromatografia gasosa-espectrometria de massa (GC-MS), para à recuperação de voláteis a partir da polpa de lulo (Solanum quitoense). Foi realizado um delineamento completamente casualizado aplicado ao tipo de solvente para à SDE/GC-MS, enquanto à HS-SPME/GC-MS foi executado um desenho de duas vias, tendo como fatores o tipo de fibra e a temperatura de adsorção. No primeiro caso foram obtidos sobretudo hidrocarbonetos, aldeídos e ésteres; no segundo foram obtidos ésteres e aldeídos. A análise de variância mostrou uma interação significativa entre o tipo de fibra, a temperatura de adsorção e os grupos funcionais.

5.
J Agric Food Chem ; 52(19): 5914-8, 2004 Sep 22.
Artigo em Inglês | MEDLINE | ID: mdl-15366842

RESUMO

The analysis of volatile emissions of coffee berries in different physiological states of ripeness was performed using dynamic headspace and gas chromatography/mass spectrometry analysis for Coffea arabica, var. Colombia. The composition of the volatiles emitted by coffee berries is dominated by very high levels of alcohols, mainly ethanol, in all stages of ripeness in comparison with other compounds. Overripe coffee berries have high volatile emissions and show a composition dominated mainly by esters followed by alcohols, ketones, and aldehydes. The lowest level compounds were monoterpenes. 2-Methyl furan was detected in various ripening stages; this compound has not been previously reported as a coffee berry volatile. The presence of ethanol and other alcohols in the volatile composition might explain the effectiveness of using traps with mixed alcohols for detection and capture of coffee berry borers.


Assuntos
Coffea/química , Besouros/fisiologia , Frutas/química , Frutas/crescimento & desenvolvimento , Álcoois/análise , Aldeídos/análise , Animais , Ésteres/análise , Cromatografia Gasosa-Espectrometria de Massas , Cetonas/análise , Monoterpenos/análise , Volatilização
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