Biblioteca do Café
URI permanente desta seção${dspace.url}/handle/123456789/1
Navegar
3 resultados
Resultados da Pesquisa
Item Perfil volátil do Coffea arabica e Coffea canephora var. Conilon por SHS-GC-MS e quimiometria(Sociedade Brasileira de Química, 2023-11-20) Lyrio, Marcos Valério Vieira; Cunha, Pedro Henrique Pereira da; Debona, Danieli Grancieri; Agnoletti, Bárbara Zani; Frinhani, Roberta Quintino; Oliveira, Emanuele Catarina da Silva; Filgueiras, Paulo Roberto; Pereira, Lucas Louzada; Castro, Eustáquio Vinicius Ribeiro deThe volatile composition of coffee exerts a substantial influence on its quality, as it defines the characteristics of the beverage. However, these compounds are influenced by factors within the coffee production chain, such as botanical origin, geography, processing methods, and roasting. Consequently, the identification of such compounds becomes a vital tool for characterizing coffees to these factors. In this context, gas chromatography with headspace extraction is widely used for aroma analysis, providing a composition closer to consumer perception. Headspace extraction offers speed, simplicity, minimal sample preparation, and no need for solvents. In this study, static headspace extraction (SHS) coupled with gas chromatography-mass spectrometry (SHS-GC-MS) was employed to establish the chemical profile of volatile compounds in Coffea arabica and Coffea canephora var. conilon and determine discriminants between the species. A total of 97 compounds, belonging to 17 chemical classes, were identified. The chemometric analysis highlighted furans, phenols, and carboxylic acids as key differentiating classes. Notably, furfuryl alcohol, acetic acid, 4-vinylguaiacol, N-acetyl-4(H)-pyridine, and N-furfurylpyrrole emerged as crucial volatile compounds. The variable selection using Fisher weight applied directly in the chromatograms, produced models consistent with relative area data, with furfuryl alcohol and 4-vinylguaiacol regions being particularly influential in differentiation.Item Café com quimioterapia: uma aplicação do planejamento fatorial fracionário 2|5-1(Sociedade Brasileira de Química, 2023-03-03) Silva, Kaique Carvalho da; Caldeira, Gabriel Rocha Figueira; Nogueira, Kenya Gomes; Canela, Maria Cristina; Filgueiras, Paulo Roberto; Souza, Murilo de OliveiraChemometrics is a subfield of chemistry that emerged from advances in analytical instrumentation and computing. When seeking to solve chemical problems that depend on many concomitants experimental variables, chemometrics can be employed in order to extract as much information as possible in the least possible number of experiments. In addition, it is possible to evaluate the important effects and interactions among the variables to understand the processes being monitored in each system. In this sense, this article aimed to develop a didactic experiment of caffeine extraction using an espresso machine, applying the 25-1 fractional factorial design. The variables studied were temperature (75 and 78 °C), pressure (2 and 15 bar), granulation (bean and ground), type of coffee (special and traditional) and period of the day (morning and afternoon) to obtain maximum extraction of caffeine. The coffee extracts obtained were analyzed using UV-Vis molecular absorption spectrophotometry. The developed experiment showed the potential to spread the application of chemometrics in the academic environment and to facilitate the teaching of fractional factorial design.Item Potencial sensorial de genótipos de Coffea canephora cultivados no estado do Espirito Santo(Embrapa Café, 2019) Correia, Radigya Meyrelles; Oliveira, Henrique Falqueto de; Romão, Wanderson; Lacerda Jr., Valdemar; Pereira, Lucas Louzada; Filgueiras, Paulo Roberto; Guaçoni, Rogerio C.; Partelli, Fabio LuizNeste estudo foram analisados sensorialmente 42 genótipos de cafés da espécie Coffea canephora cultivados no Norte do Espirito Santo de acordo com a metodologia da Uganda Coffee Development Authority – (UCDA) por especialistas na área (Q-Graders). As características genéticas juntamente com as condições ambientais determinam a qualidade de bebida do café, de modo que a seleção de novas cultivares de café requer informações de atributos sensoriais a fim de avaliar a qualidade do café. Os resultados atribuíram ao café nº 42 o maior valor na avaliação global e indicaram o atributo doçura e conjunto como as variáveis mais significativa na construção do modelo. Um número significativo de genótipos apresentaram bons resultados e pesquisas na área ainda estão em andamento para obter resultados mais concretos no futuro, baseado em mais uma ou duas colheitas.