Brew Methods Effect on Coffee Flavor and Aroma

Coffee is one of the most popular aromatic hot drinks in the world. Numerous coffee brewing methods have been developed to make a cup of coffee. In industry, coffee flavor and aroma is determined by using a method called cupping, but in order to quantitate flavor and aroma in coffee, descriptive sensory is a better option. This study identified how brew methods influence coffee aroma and flavor. Four different roast level Folgers® commercial coffee (Breakfast blend, Classic roast, 100% Colombia and Black silk) were brewed by four brewing methods (pour over, drip, French press, and cold brew) and were tested using a trained descriptive panel using the World Coffee Research (WCR) coffee lexicon. Twenty-five main aroma attributes and thirty-five main flavor and texture attributes of coffee were used. Cold brew method produced the mildest coffee among the four brew methods while drip produced a much stronger coffee. The sensory aroma and flavor differences between different coffee types were not as great as differences between brew methods. From chemical tests, Brix percentage and TDS (Total Dissolved Solids) differed across coffee types and brew methods. Chemical attributes were closely associated with overall impact, body fullness, bitter basic taste and roasted and burnt flavor aromatics. Volatile compounds (n = 271) were identified. Forty-four volatile aromatic compounds differed across coffee types while thirty-seven volatile aromatic compounds differed across brew methods. Folgers® 100% Colombia coffee showed a difference from the other three coffee types by showing higher (P < 0.05) amount of volatile compounds, especially in 2-butenal, and 1-(2-hydroxyphenyl)-ethanone (beany aroma). Cold brewed Folgers® 100% Colombia was high on sweet, overall sweet flavor as well as 2,3-hexanedione. The preparation method is a critical factor affecting coffee flavor and aroma. Coffee from the cold brew method was more fruity, floral and sweet whereas coffee from the drip or French press methods were roasted, burnt, and ashy

Quantitative Structure-Property Relationships for Predicting the Retention Indices of Fragrances on Stationary Phases of Different Polarity

El objetivo de este trabajo fue el desarrollo de relaciones cuantitativas estructura–propiedad predictivas para el modelado de índices de retención (I) de fragancias, medidas en tres fases estacionarias de diferente polaridad: DB–225MS, HP5–MS y HP–1. Se ha prestado particular atención al curado de los datos experimentales. Posteriormente, se usó el método de subconjuntos balanceados (BSM) para dividir cada base de datos en grupos de calibración, validación y predicción. Los modelos se construyeron a partir de 1819 descriptores moleculares independientes de la conformación, los cuales fueron analizados mediante el método de reemplazo (RM) para la selección de los mismos, con la finalidad de obtener los mejores modelos. Para la fase estacionaria DB–225MS se obtuvo un modelo basado en cuatro descriptores, mientras que para las columnas HP5–MS y HP–1 se propusieron modelos con tres descriptores. Los modelos fueron validados mediante validación cruzada de dejar–uno–fuera y dejar–varios–fuera, así como otros criterios de validación. Adicionalmente, con la finalidad de cumplir los principios propuestos por la Organization for Economic Co–operation and Development (OECD), la capacidad predictiva de los modelos se evaluó mediante la predicción de los índices de retención del grupo externo de predicción, el dominio de aplicabilidad fue apropiadamente definido y se realizó una interpretación de cada descriptor molecular involucrado.The purpose of this work was to develop predictive quantitative structure–property relationships for modeling the retention indices (I) of fragrances measured in three stationary phases of different polarities: DB–225MS, HP5–MS and HP–1. Attention was paid to the curation of the experimental data. Subsequently, the Balanced Subsets method (BSM) was used to split each dataset into training, validation and test sets. Models were established by using 1819 conformation–independent molecular descriptors which were analyzed by the replacement method (RM) variable subset selection in order to obtain the optimal models. A four–descriptor model was obtained for the DB–225MS stationary phase while a three–parametric model was proposed for both the HP5–MS and HP–1 columns. Models were validated by means of the leave–one–out and leave–many–out cross–validation procedures, as well as other validation criteria. Moreover, in order to accomplish the principles proposed by the Organization for Economic Co–operation and Development (OECD), the model’s predictive ability was measured by predicting retention indices of the external test set. The applicability domain was properly defined and the interpretation of each of the molecular descriptors used in this study was provided.Fil: Rojas Villa, Cristian Xavier. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; ArgentinaFil: Duchowicz, Pablo Román. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas. Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Instituto de Investigaciones Fisicoquímicas Teóricas y Aplicadas; ArgentinaFil: Tripaldi, P.. Universidad de Azuay; EcuadorFil: Pis Diez, Reinaldo. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - La Plata. Centro de Química Inorgánica "Dr. Pedro J. Aymonino". Universidad Nacional de La Plata. Facultad de Ciencias Exactas. Centro de Química Inorgánica "Dr. Pedro J. Aymonino"; Argentin

Scientific Opinion on Flavouring Group Evaluation 13 Revision 3 (FGE.13Rev3) : furfuryl and furan derivatives with and without additional side-chain substituents and heteroatoms from chemical group 14

Acknowledgements: The Panel wishes to thank the following hearing expert for the support provided to this scientific output: Karin Nørby.Publisher PD

In-vitro Antibacterial, Antifungal and cytotoxic activity of cobalt (II), copper (II), nickel (II) and zinc (II) complexes with furanylmethyl- and thienylmethyl-dithiolenes: [1, 3-dithiole- 2-one and 1,3-dithiole-2-thione]

Some antibacterial and antifungal furanylmethyl-and thienylmethyl dithiolenes and, their Co(II), Cu(II), Ni (II) and Zn (II) complexes have been synthesized, characterized and screened for their in vitro antibacterial activity against four Gram-negative; Escherichia coli, Pseudomonas aeruginosa, Salmonella typhi and Shigella flexeneri, and two Gram-positive; Bacillus subtilis and Staphylococcus aureus bacterial strains, and for in-vitro antifungal activity against Trichophyton longifusus, Candida albicans, Aspergillus flavus, Microsporum canis, Fusarium solani and Candida glaberata. All compounds showed significant antibacterial and antifungal activity. The metal complexes, however, were shown to possess better activity as compared to the simple ligands. The brine shrimp bioassay was also carried out to study their in-vitro cytotoxic properties

The Human Nose as a Chemical Sensor in the Perception of Coffee Aroma: Individual Variability

The flavor of foods and beverages is generally composed of a mixture of volatile compounds, however not all the molecules that form an aroma are sensorially relevant. The odor-active compounds present in a mixture are different for each subject, both in quantitative and qualitative terms. This means that the ability of the human nose to act as a chemical sensor varies among individuals. In this study, we used the headspace of roasted coffee beans as a complex olfactory stimulus and, by means of the coupled Gas Chromatography-Olfactometry (GC-O) technique, the single components of coffee flavor were separated. Each subject, previously classified for his/her olfactory status (normosmic, hyposmic or anosmic) by means of the Sniffin' Sticks battery (composed of Threshold, Discrimination and Identification subtests), had to identify and evaluate each smelled molecule. The results show that the individual ability to detect individual compounds during the GC-O experiments and the odor intensity reported during the sniffing of pen #10 (the pen of the identification test) containing coffee aroma were related to TDI olfactory status (based on the score obtained from the sum composed of Threshold, Discrimination and Identification scores). We also found that the number of total molecules and of molecules smelling of coffee is linearly related to the TDI olfactory score. Finally, the odor intensity reported when sniffing pen #10 containing coffee aroma is positively correlated with the number of molecules detected and the average intensity reported. In conclusion, our findings show that the human perception of both individual compounds and complex odors is strongly conditioned by the olfactory function of subjects

The Deep Purple Color and the Scent are Two Great Qualities of the Black Scented Rice (Chakhao) of Manipur

Specialty rice varieties with unique properties such as unique color, flavor, aroma and nutraceutical qualities are increasingly in demand other than the traditional white rice varieties. Black rice has various nutraceutical properties with high anthocyanin content and the anthocyanin antioxidants are very important in preventing various diseases. Black scented rice of Manipur, which are commonly known as Chakhao, are deep purple colored and scented, and are very glutinous, as well. Two Chakhao cultivars, Chakhao Poireiton and Chakhao Amubi, were shown to have high anthocyanin and phenolics content and strong antioxidant activity. The main anthocyanins of Chakhao Poireiton are delphinidin 3‐galactoside, delphinidin 3‐arabinoside, cyanidin 3‐galactoside and cyanidin 3‐glucoside and that of Chakhao Amubi are delphinidin 3‐galactoside, delphinidin 3‐arabinoside and cyanidin 3‐galactoside. By GC‐MS analysis, a cross mixture of 26 volatile compounds from Chakhao Poireiton and 11 volatile compounds from Chakhao Amubi were found to be responsible for emanating the aroma. Among the complex mixture of volatile oil components, n‐hexadecanoic acid and octadec‐9‐enoic acid were the most abundant in Chakhao Poireiton and 17‐pentatriacontene, l3‐octadecenal (Z) and hexadecenoic acid eicosyl ester in Chakhao Amubi

Brew Methods Effect on Coffee Flavor and Aroma

Coffee is one of the most popular aromatic hot drinks in the world. Numerous coffee brewing methods have been developed to make a cup of coffee. In industry, coffee flavor and aroma is determined by using a method called cupping, but in order to quantitate flavor and aroma in coffee, descriptive sensory is a better option. This study identified how brew methods influence coffee aroma and flavor. Four different roast level Folgers® commercial coffee (Breakfast blend, Classic roast, 100% Colombia and Black silk) were brewed by four brewing methods (pour over, drip, French press, and cold brew) and were tested using a trained descriptive panel using the World Coffee Research (WCR) coffee lexicon. Twenty-five main aroma attributes and thirty-five main flavor and texture attributes of coffee were used. Cold brew method produced the mildest coffee among the four brew methods while drip produced a much stronger coffee. The sensory aroma and flavor differences between different coffee types were not as great as differences between brew methods. From chemical tests, Brix percentage and TDS (Total Dissolved Solids) differed across coffee types and brew methods. Chemical attributes were closely associated with overall impact, body fullness, bitter basic taste and roasted and burnt flavor aromatics. Volatile compounds (n = 271) were identified. Forty-four volatile aromatic compounds differed across coffee types while thirty-seven volatile aromatic compounds differed across brew methods. Folgers® 100% Colombia coffee showed a difference from the other three coffee types by showing higher (P < 0.05) amount of volatile compounds, especially in 2-butenal, and 1-(2-hydroxyphenyl)-ethanone (beany aroma). Cold brewed Folgers® 100% Colombia was high on sweet, overall sweet flavor as well as 2,3-hexanedione. The preparation method is a critical factor affecting coffee flavor and aroma. Coffee from the cold brew method was more fruity, floral and sweet whereas coffee from the drip or French press methods were roasted, burnt, and ashy

Capillary electrophoresis-mass spectrometry metabolic fingerprinting of green and roasted coffee

The aim of this work was to develop a capillary electrophoresis-mass spectrometry (CE-ESI-QToF-MS) method to carry out the metabolic fingerprinting of green and roasted coffee samples (Arabica variety). To evaluate changes in the metabolic profiles of coffee occurring along the roasting process, green coffee beans were submitted to different roasting degrees. The effect of different parameters concerning the electrophoretic separation (background electrolyte, temperature, voltage, and injection time), the MS detection (temperature and flow of drying gas, sheath gas of jet stream temperature, and capillary, fragmentator, nozzle, skimmer, and octapole voltages) and the sheath liquid (composition and flow rate) was studied to achieve an adequate separation and to obtain the largest number of molecular features. The analyses were carried out in positive ESI mode allowing to detect highly polar cationic metabolites present in coffee beans. Non-supervised and supervised multivariate analyses were performed showing a good discrimination among the different coffee groups. Those features having a high variable importance in the projection values on supervised analyses were selected as significant metabolites for their identification. Thus, 13 compounds were proposed as potential markers of the coffee roasting process, being 7 of them tentatively identified and 2 of them unequivocally identified. Different families of compounds such as pyridines, pyrroles, betaines, or indoles could be pointed out as markers of the coffee roasting process. (C) 2019 Elsevier B.V. All rights reserved