Biblioteca do Café

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Agora exibindo 1 - 10 de 95
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    “Emocoffee”: um novo instrumento para avaliação da resposta emocional e afetiva do consumidor ao café
    (Universidade Federal de Viçosa, 2024-05-06) Costa, Ana Alice da Silva Xavier; Minim, Valéria Paula Rodrigues; Lima Filho, Tarcísio; Noronha, Regina Lúcia F. de
    O papel das emoções dentro do Estudo do Consumidor vem sendo alvo de intensas discussões pela comunidade científica nos últimos anos. Os estudos vêm evidenciando que as emoções possuem grande impacto no comportamento e nas decisões de consumo, inclusive para os alimentos. Para o setor cafeeiro, esse cenário não é diferente. Pesquisas recentes demonstraram que o café é capaz de evocar diferentes emoções e por este motivo instrumentos capazes de avaliar as emoções associadas ao café vêm sendo desenvolvidos. No entanto, ainda são poucos os questionários disponíveis na literatura desenvolvidos especificamente para o café. Observa- se que nenhum deles foi construído considerando o público brasileiro, o qual possui uma relação diferenciada com esta matéria-prima, já que o Brasil se enquadra como o maior produtor e o segundo maior consumidor do mundo. Além disto, os questionários já disponíveis apresentam um grande número de termos, sem nenhum contexto, que poderão contribuir para ambiguidade de significados. Assim, objetivou-se propor um novo instrumento de avaliação de emoções associadas a café voltado para o consumidor brasileiro e que apresente um número reduzido de termos dentro de um contexto. Para isso, este trabalho foi dividido em três capítulos. No primeiro, apresentou-se a etapa de levantamento de termos para a construção do questionário, utilizando para isto técnica de entrevista associada à análise sensorial. O conteúdo das entrevistas foi avaliado por meio de técnicas de análise lexical com auxílio do software IRaMuTeQ. A combinação entre técnicas sensoriais e de análise léxica mostrou-se como um excelente instrumento para a captação da linguagem real dos consumidores na expressão de suas emoções relacionadas ao café. Assim, o instrumento desenvolvido pode ser utilizado na construção de um vocabulário específico para o público estudado. No segundo capítulo, os termos obtidos na etapa anterior foram estudados e refinados por um grupo de foco composto de consumidores de café. Além de refinar os termos, os consumidores também sugeriram que o questionário utilizado apresentasse frases completas ao invés de termos soltos e que fosse acompanhado de imagens, com o intuito de reduzir a ambiguidade dos termos. A partir das sugestões dos participantes do grupo de foco, o questionário foi construído e aplicado para a avaliação da resposta emocional e afetiva à diferentes amostras de café. O questionário construído foi denominado de EmoCoffee e foi efetivo na diferenciação das amostras tendo como base a aceitação e as emoções evocadas. O terceiro capítulo aborda a aplicação do EmoCoffee para a avaliação do efeito da embalagem sobre a resposta afetiva ao café. Este instrumento se adequou ao uso de uma escala de intensidade pois conseguiu captar mudanças no perfil emocional e de aceitação das amostras de café, quando este foi servido na presença de diferentes embalagens. Assim, o EmoCoffee é útil na avaliação do perfil emocional de diferentes tipos de bebida de café, avaliação de contexto de consumo bem como no estudo do impacto de diversos elementos associados ao café, como as informações contidas nas embalagens. Por ser uma escala específica, este novo instrumento contribui para que empresas, pesquisadores e entusiastas da área tenham acesso a informações mais claras e profundas sobre a experiência emocional do consumo desta bebida. Por ser uma escala curta, sua aplicação é fácil e prática, tornando-se mais vantajosa que outros instrumentos disponíveis na literatura.
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    Sensory perception of coffee consumers as a function of different genotypes and extraction methods
    (Universidade Federal Rural de Pernambuco, 2024-09-30) Nadaleti, Denis Henrique Silva; Sousa, Maísa Mancini Matioli de; Ribeiro, Michele Nayara; Vilela, Diego Júnior Martins; Pereira, Dyanna Rangel; Carvalho, Gladyston Rodrigues
    Coffee is one of the most consumed beverages in the world, with unique organoleptic characteristics of aroma and flavor, also varying according to the several extraction methods. Therefore, the objective of this study was to investigate whether the different Arabic coffee genotypes prepared by various extraction methods would influence amateur consumers’ perception of sensory and hedonic judgments of specialty coffee. A large-sample experiment (n = 270) was conducted in a coffee shop at the Universidade Federal de Lavras and participants were divided into three groups according to the evaluated genotypes (Bourbon Amarelo, Pacamara and Híbrido de Timor), who tasted four samples, varying to the extraction methods (‘Conventional Brewed’, Hario V60, French Press and Espresso). From the results obtained, it is possible to conclude that there is a change in the sensory perception of aromas and flavors of coffees in all genotypes studied in the four extraction methods, as well as in the acceptance and purchase intention by consumers.
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    Physicochemical and sensory analysis of coffee: A determination in different parts of the plant
    (Universidade Federal de Lavras, 2024-07-29) Sousa, Rachel Machado de; Paiva, Leandro Carlos
    The quality of the Arabica coffee drink (Coffea arábica L) is the result of the interaction of several factors, such as climatic conditions, terroir, altitude, nutritional factor, management aspects, stage of fruit maturation, harvest, among others. The objective was to evaluate the physical-chemical quality of coffee fruits, through the soluble solids content of coffee beans, in different parts of the plant, in order to define which position/location on the plant presents the best results in relation to sensory attributes of the drink. The analysis of soluble solids (SS) in ºBrix of cherry and raw coffee, mass grains (MMG) and sensory evaluation, the Catuaí IAC 144 variety presented better results in relation to the Paraíso MG 419- 1 variety. Regarding electrical conductivity (EC), total titratable acidity (TTA) of raw coffee, pH, color the results of the two varieties were representative for quality, the values found in the analyzes are within the defined ranges. The experimental design used was randomized blocks and each variety was harvested in three blocks. Each block consisted of a plant, each plant was divided into twelve subdivisions. The treatments were arranged in a 12x2x3 factorial scheme and subjected to analysis of variance (ANOVA) and the means compared using the Scott Knott post hoc test with a significance level (p-value ≤ 0.05). The correlation matrix was used between the variables under study, in order to verify whether there is a linear relationship or not between the variable’s soluble solids ºBrix of cherry and raw coffee, aroma and body of the drink with the final average score of the tasters. Interpreting the generated equation, there is an association between body and final score, when increasing one unit in the body, an increase of 2.21 in the final score is expected. The positions on the coffee plant, upper third and lower third, in relation to the varieties Catuaí IAC 144 and Paraíso MG 419-1, were the most promising from the perspective of the results found in the physical-chemical and sensorial analysis.
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    Influence of water quality on CO2 degassing and sensory attributes in lampung robusta espresso
    (Universidade Federal de Lavras, 2024-07-05) Haviz, Muhammad; Djana, MIftahul; Nandini, Ni Putu Ariessa; Eltri, Amandha Putri; Fahrani, Nadila Aura; RIna, Oktaf
    Water quality plays a crucial role in shaping the sensory attributes and overall taste experience of Espresso Coffee (EC). This study aimed to investigate the influence of water quality parameters, specifically acidity (pH) and total dissolved solids (TDS), on CO2 degassing kinetics and sensory characteristics in Lampung Robusta espresso. Five different brands of bottled water were utilized for EC extraction, and their impact on CO2 degassing behavior, pH, TDS, and sensory attributes was evaluated. Analysis of variance (ANOVA) and Tukey’s Honest Significant Difference (HSD) post-hoc tests were employed to assess the significance of differences in CO2 degassing levels among water brands. Two-way ANOVA was used to examine variations in pH and TDS before and after espresso extraction. Sensory evaluation by trained panelists was conducted to assess sensory characteristics. ANOVA revealed significant differences in CO2 degassing levels among water brands (F= 41.21, p= 1.41E-16), with specific brand pairs exhibiting significant variations identified by Tukey’s HSD test. Brand D water maintained the lowest average CO2 emissions (865 ppm) compared to other brands, indicating its potential in stabilizing the release of CO2 during the EC extraction. Two-way ANOVA demonstrated significant differences in pH (F= 38380.37, p < 0.001) and TDS (F= 1178385, p < 0.001) among water brands before and after espresso extraction. The highest TDS elevation observed in brand A post-extraction (7258 ppm) suggests a potential for over-extraction. The lowest final pH in EC was recorded with brand B (5.11) and the highest final pH of brand A (5.32) Sensory evaluation revealed variations in aroma, acidity, bitterness, body, crema, sweetness, mouthfeel, and flavor notes among espresso samples prepared with different water brands. This study highlights the significant impact of water quality on CO2 degassing and sensory attributes in Lampung Robusta espresso.
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    Descriptive sensory tests for evaluating Coffea arabica: A systematic review
    (Universidade Federal de Lavras, 2024-04-20) Nascimento, Manuella Oliveira; Ombredane, Alicia Simalie; Oliveira, Livia de Lacerda de
    Coffee is a beverage whose price is closely related to the characteristics of its flavor, necessitating reliable sensory tests. To quantify their sensory attributes, classic sensorial methods such as Quantitative Descriptive Analysis (QDA) can be useful. However, uncertainties persist due to protocol variations, which made uncertain the quality of these protocols in evaluating coffee. This study aimed to conduct a systematic review to assess the quality of QDA protocols used for assessing Coffea arabica’s sensory attributes. The review encompassed various critical protocols control points, including pre-test procedures, coffee processing and preparation techniques, test application and data collection procedures. It was also summarized key attributes, highlighting factors impacting coffee’s sensory traits and bias risk of the studies. As the main results, it was saw that the studies have many limitations, such as not citing or controlling critical points in the tests procedures and application, which made most studies having a medium-high bias rating. The primary sensory results findings of the studies included topics such as the impact of brewing time, chemical compounds associated with sensory attributes and the effect of various roasting techniques on the sensory qualities of coffee. In conclusion, standardizing sensory evaluations in future research could enhance consistency and accuracy, yielding less biased results.
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    Effect of storage duration on phenolics stability in ready-to-drink coffee beverage
    (Universidade Federal de Lavras, 2024-06-20) Herawati, Dian; Davin, Christophorus; Yuliana, Nancy Dewi; Yulianti, Yulianti
    Ready-to-drink (RTD) coffee is one of the innovations in coffee beverages that is widely circulated in the market and is quite popular among various groups of people. This study aimed to partially validate the Folin-Ciocalteu method for phenolic compounds analysis in ready-to-drink (RTD) coffee and determine the effect of storage time on the stability of phenolic compounds in RTD coffee. Coffee drinks were made from Robusta coffee extract added with other ingredients (sugar and potassium sorbate), pasteurized, hot filled into plastic cups, and stored at room temperature (25 – 28 oC) for 0, 2, 4, 6, and 8 weeks. Two proposed methods (Folin-Ciocalteu methods) for routine phenolic analysis (Total phenolic content (TPC) and total tannin content (TTC)) in RTD coffee were partially validated. In general, partial validation parameters of TPC gave more satisfying results, such as linearity (R2 = 0.9991); precision (RDS < 2/3 RSDHorwitz); recovery (109%) and sensitivity (LOD = 14.20 mg L-1). Phenolic stability in RTD coffee was evaluated using the Folin-Ciocalteu method (TPC and TTC) and HPLC method (individual caffeoylquinic acids (CQAs) (3-CQA, 4-CQA, and 5-CQA)). In general, TTC values in all storage time were higher than TPC values because the TTC method had higher recovery (132%). Furthermore, the three parameters observed (TPC, TTC and CQAs) experienced significant degradation during storage. The decrease percentage of TPC and TTC during 8 weeks of storage was 11% (from 63 to 55 mg/100 mL) and 10% (160 to 143 mg/100 mL), respectively. Meanwhile, 5-CQA was the most sensitive CQAs and its degradation for 8 weeks of storage reached 19% (from 28 to 23 mg/100mL ). TPC is recommended for monitoring the effect of storage duration on phenolic compound stability in RTD coffee and analysis of 5-CQA as the most unstable individual phenolic may support the monitoring.
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    Effect of demucilagination and soaking in water with organic acids on the microbial, chemical, and sensory characteristics of coffee (Coffea arabica)
    (Universidade Federal de Lavras, 2024-06-17) Ponce, Jorge Alfredo Cardona; Mejía, Luis Fernando Maldonado
    There are divided opinions regarding sensory quality of mechanically demucilaginated (MD) coffee versus coffee that has undergone conventional fermentation (biological demucilagination). Fermenting and washing (wet process) requires high amounts of water that has contaminating effects upon its completion. Studies indicate that MD with soaking in organic acids could develop similar sensory quality to wet processed coffee. Organic acids are bioactive compounds that are naturally produced during conventional fermentation, which is why coffee has unique characteristics in the final cup profile. This study was conducted to assess the effects of soaking with organic acids (citric, ascorbic, and acetic) on the microbial, chemical, and sensory attributes of MD coffee. A Completely Randomized Design (CRD) was used, with a factorial arrangement (2×4+2) for a total of 10 treatments. The treatments were two soaking times (24 and 48 hours) and four soaking solutions (citric, ascorbic, acetic acid and water) in coffee with mechanical demucilagination, one treatment with mechanical demucilagination and one with fermentation and washing, both without soaking or acids. Microbiological counts of fungi, yeasts, and lactic acid bacteria (LAB) were carried out before and after soaking. Sensory characteristics were evaluated through cupping and chemical content and properties were studied by liquid chromatography and spectrophotometry. Microbial population demonstrated normal succession throughout the experiment with LAB been the most prevalent family during MD and fermentation. Soaking coffee in acid solutions maintained overall cupping scores with different attributes being detected by panelists. Phenolic compounds, caffeine and chlorogenic acids increased in soaked samples (acetic acid) but were similar to the control (fermentation). Flavonoid content ranged from 22 to 35 mg EC/g and was higher in samples soaked in acids compared to the controls. Green coffee extracts in general showed antioxidant activities greater than 80.9% comparable to other studies. Soaking time did not improve the quality characteristics of the coffee, but the type of acid used was able to modify the content and proportion of various families of chlorogenic acids in green coffee and total polyphenols, while maintaining sensory properties in comparison to fermented coffee.
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    Effect of extraction processing parameters using a ribbon blender on the physicochemical properties of coffee
    (Universidade Federal de Lavras, 2024-07-03) Barriga, Paula Andrea Mayorga; Pardo, Ruth Yolanda Ruiz; Moreno, Fabian Leonardo Moreno
    In this work, the effect of the water-coffee ratio, time, and stirring speed, on the total soluble solids, extraction rate, titratable acidity, and extraction yield was evaluated for the percolation of coffee in a horizontal ribbon blender equipment. The coffee extract was obtained in a pilot unit at a constant temperature of 85°C and varying the water-coffee ratio from 4:1 to 10:1; the stirring speed between 30 and 95 RPM and the extraction time from 10 to 60 minutes. It was determined that the water-coffee ratio was the factor that had a significant influence on all the response variables, while time and stirring were significant for the extraction rate and titratable acidity. The optimal setup among the studied conditions was using a water temperature of 85°C, a water-coffee ratio of 4:1, and a stirring speed of 66 RPM for ten minutes. At these conditions, an extract of 5.85% TDS, 14.54% as yield, an extraction rate of 654.8 g/h, and a content of 5.62 mg of CGA/mL was obtained. Hence, this study presents an alternative process to obtain coffee extract in producing soluble coffee at a low industrial scale.
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    Roasting variations and brewing methods in the preparation of clear Coffee Beverages from Gayo Arabica Coffee
    (Universidade Federal de Lavras, 2024-07-29) Sulaiman, Ismail; Marsyanda; Erika, Cut
    Coffee drinks are trendy drinks around the world, and they usually contain caffeine. However, this research focuses on creating a coffee drink that does not contain caffeine so that those who cannot consume it can enjoy it. The resulting coffee drink is a colorless coffee drink. The coffee production process initially produces a black-colored drink, but it can turn it into a clear-colored drink through distillation and chemical methods. This research aims to study the process of making clear coffee by varying roasting and brewing levels with various variations to obtain clear-colored coffee and low caffeine levels. Preparation of clear coffee drinks is done by brewing espresso and Tobruk, which is then analyzed for pH, caffeine, and color tests on the results of the clear coffee drink. Based on the ranking test on each parameter tested on clear coffee drinks, the best treatment is using the distillation method, espresso brewing, and medium roasting level. The analysis results of this selected formulation produced a transparent beverage color (clear), pH 3.5, and caffeine levels of 4.639 mg/mL.
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    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 de
    The 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.