Predicting best planting location and coffee cup quality from chemical parameters: An evaluation of raw Arabica coffee beans from São Paulo over two harvests.

Arabica coffee is one of the most consumed beverages in the world. The chemical components present in raw Arabica coffee beans (RACB) are directly related to the cup quality of the beverage. Environmental and genetic factors influence the content and profile of these components. Then, this work aimed to evaluate different chemical parameters of RACB from 3 varieties planted in 3 different experimental farms located within the "Alta Mogiana" terroir harvested in 2021 and 2022 to identify a better variety for each farm to produce a high cup quality Arabica coffee. The harvest period had a strong influence on most of the studied parameters because atypical weather conditions occurred in the 2021 harvest. The RACB harvested in 2022 yielded better results and supposedly will produce a beverage of high cup quality. Samples harvested in this period presented mainly average moisture levels closer to optimum (11.02 against 8.56 % in 2021); low total titratable acidity (98.00 against 169.75 mL 0.1 M NaOH/100 g in 2021); high amounts of free amino acids (0.96 against 0.93 g GAE/100 g in 2021), low amounts of CGA (4.27 against 4.85 g/100 g in 2021) and caffeine (1.08 against 1.76 g/100 g in 2021) and high amounts of trigonelline (1.12 against 0.96 g/100 g in 2021). The Rome Sudan variety had the best combination of chemical results, mainly when cultivated in Farm 2 in 2022, presenting high amounts of protein content (15.24 %) and free amino acids (0.96 g GAE/100 g), low total titratable acidity (98.3 mL 0.1 M NaOH/100 g), low amounts of CGA (4.55 g/100 g) and caffeine (1.29 g/100 g) and high amounts of trigonelline (1.11 g/100 g). The analysis of chemical compounds could predict the best farm to cultivate each variety studied and was a guide to foresee a higher cup quality of RACB beverages.

Enhancing Sensory Quality of Coffee: The Impact of Fermentation Techniques on Coffea arabica cv. Catiguá MG2.

Fermentation, a critical post-harvest process, can be strategically manipulated to augment coffee quality. This enhancement is achieved through the activity of microorganisms, which generate metabolites instrumental in the formation of distinct sensory profiles. This study investigated the impact of different fermentation methods on the quality of coffee beverages, specifically utilizing the Catiguá MG2 variety. The experimental setup involved fermenting the coffee in 200 L bioreactors, employing both natural and pulped coffee beans. The fermentation process utilized was self-induced anaerobic fermentation (SIAF), conducted in either a solid-state or submerged medium over a 96 h period. Analytical sampling was conducted initially and at 24 h intervals thereafter to quantify the concentration of sugars, alcohols, and organic acids. Sensory evaluation was performed using the established protocols of the Specialty Coffee Association (SCA). The outcomes of this investigation reveal that fermentation substantially enhances the quality of coffee, with each treatment protocol yielding divergent profiles of acids and alcohols, thereby influencing the sensory characteristics of the resulting beverage. Notably, superior quality beverages were produced from naturally processed coffee subjected to solid-state fermentation for durations exceeding 24 h. These findings underscore the significant influence of fermentation techniques and duration on the sensory attributes and overall quality of coffee.

Evaluation of Arabica Coffee Fermentation Using Machine Learning.

This study explores the variances in the organic, chemical, and sensory attributes of fermented coffee beans, specifically examining how post-harvest processes influence cup quality. Coffee fruits from the Catuaí IAC-144 variety were processed using both natural coffee (NC) and pulped coffee (PC) methods. The fruits were then subjected to self-induced anaerobic fermentation (SIAF) using one of the following fermentation methods: solid-state fermentation (SSF) or submerged fermentation (SMF). Within these methods, either spontaneous fermentation (SPF) or starter culture fermentation (SCF) was applied. Each method was conducted over periods of 24, 48, and 72 h. For this purpose, two-hundred-liter bioreactors were used, along with two control treatments. Numerous parameters were monitored throughout the fermentation process. A comprehensive chemical profiling and sensory analysis, adhering to the guidelines of the Specialty Coffee Association, were conducted to evaluate the influence of these fermentation processes on the flavor, aroma, and body characteristics of the coffee beverage across multiple dimensions. Data analysis and predictive modeling were performed using machine learning techniques. This study found that NC exhibited a higher production of acids (citric, malic, succinic, and lactic) compared to PC, resulting in distinct chemical and sensory profiles. The decision tree showed that fructose and malic and succinic acids were identified as the main factors enhancing sensory notes during cupping. SMF promoted higher concentrations of lactic acid, while SSF led to increased ethanol content. Consequently, the SIAF process enhances the sensory quality of coffee, adding value to the product by generating diverse sensory profiles.

Evaluation of genetic divergence of coffee genotypes using the volatile compounds and sensory attributes profile.

The quality of the coffee beverage is related to the chemical, physical, and sensory attributes of the coffee beans that vary with the geographic location of the crop, genetic factors, and post-harvest processing. So, the objective of this study was to evaluate the genetic divergence of 27 genotypes of Coffea canephora using the volatile compounds and sensory attributes profile to select genotypes that produce a coffee beverage with high sensory quality. This genetic diversity was estimated from the Euclidean distance matrix using non-standard data and the Unweighted Pair-Group Method Using Arithmetic Averages (UPGMA). The 2-furyl-methanol, 4-ethenyl-2-methoxyphenol, furfural, 5-methylfurfural, methylpyrazine, and 2,6-dimethylpyrazine were predominating volatile compounds in the genotypes. The sensory attributes had a positive Pearson's correlation with the total score. The volatile compounds had a different relative contribution to the genetic divergence between the genotypes of C. canephora. The 4-ethenyl-2-methoxyphenol, 2-furyl-methanol, and furfural were volatile compounds that most contributed to the formation of the groups in the UPGMA dendrogram. The relative contribution of sensory attributes to dissimilarity among genotypes was 6.42% to 20.20%. Therefore, this study verified the relative contribution of volatile compounds, in specially 4-ethenyl-2-methoxyphenol, 2-furyl-methanol, and furfural, and sensory attributes (flavor, mouthfeel, and bitterness/sweetness) to the genetic divergence between the genotypes of the three clonal varieties. Thus, this work points out compounds that positively contribute to the sensory quality of the Conilon coffee beverage.

Characterization of bioactive, chemical, and sensory compounds from fermented coffees with different yeasts species.

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.

Political architectures in the municipality of Varre-Sai (Brazil): for sustainabilities in 'specialty coffees' production management.

The coffee cultivation has historically had great importance in Rio de Janeiro's social-spatial organization, and it is once again in the spotlight of the state's economic scenario. The novelty is that the local production has been renewed, and, now, the state surpasses the old status of 'low-quality coffee producer' and achieves the 'specialty coffee' market which, in addition to quality, also values environmental, social and economic sustainabilities . This change has caused a series of transformations in the social-spatial and economic realities of some municipalities in the state of Rio de Janeiro. This article analyses the possible sustainabilities existing in the production process of this new coffee profile, based on the reality of the municipality of Varre-Sai, located in the northwest of Rio de Janeiro state. The objective is to find out the main actors and to elucidate the political network involved in this process.

Quality of arabic coffee under different processing systems, drying methods and altitudes / Qualidade do café arábico sob diferentes sistemas de processamento, métodos de secagem e altitudes

The quality of coffee is one of the most important requirements in the commercialization of the product, and the post-harvest stage is decisive in the production of excellent coffees. The region of Mutum, MG, Brazil, is predominantly coffee-growing, with high potential for the production of specialty coffees. Due to the social and economic importance of coffee production in the Matas de Minas region, research has been demanded with the aim of providing technological information that provides improvements in quality and consequent price aggregation of the coffee bag. Among the several factors that may affect coffee quality are the processing system, the drying method and the altitude. Thus, the objective of this work was to evaluate the quality of Arabica coffee at different altitudes, submitted to different processing systems and drying methods. The work was conducted at the Cabeceira do Imbiruçu, in a randomized complete block design,with treatments arranged in a scheme comprising sub-subdivided plots (2 x 2 x 2), with four replications. In the plots, the two altitudes (850 and 1050 m), in the subplotsthe two processingsystems (dry (natural) and wet (peeled cherry)) and in the sub-subplotstwo drying methods (cement and suspended yard, both covered). Sensory and electrical conductivity analyzes were performed. The fruits of coffee trees located at altitudes of 1050 m have sensory attributes superior to those of altitudes of 850 m. The best results of the coffee flavor and aroma sensory attributes were obtained in the wet processing system when compared to a dry (natural) processing system. The electrical conductivity of the coffee beans obtained in the wet processing system was lower than that obtained in the dry processing system (natural), which gives a better beverage quality. Drying methods in suspended yard and cement yard, both with plastic cover and if technically conducted, do not influence the sensory characteristics of the Arabica coffee.

A qualidade do café é um dos requisitos mais importantes na comercialização do produto, sendo a etapa de pós-colheita determinante na produção de cafés de excelência. A região de Mutum, MG, Brasil, é predominantemente cafeeira, com elevado potencial de produção de cafés especiais. Em razão da importância social e econômica da cafeicultura para a região das Matas de Minas, pesquisas têm sido demandadas com o intuito de fornecer informações tecnológicas que proporcionem melhorias na qualidade e consequente na agregação do preço da saca de café. Dentre os diversos fatores que podem afetar a qualidade do café destacam-se o sistema de processamento, o método de secagem e a altitude. Assim, objetivou-se com a realização deste trabalho, avaliar a qualidade do café arábica em diferentes altitudes, submetido a diferentes sistemas de processamento e métodos de secagem. O trabalho foi conduzido na propriedade cabeceira do Imbiruçu, em um delineamento experimental de blocos casualizados, com os tratamentos dispostos em um esquema de parcelas sub-subdivididas (2 x 2 x 2), com quatro repetições, sendo nas parcelas, as duas altitudes (850 e 1050 m), nas subparcelas, os dois sistemas de processamento (seco (natural) e úmido (cereja descascada)) e nas subparcelas, dois métodos de secagem (cimento e terreiro suspenso, ambos cobertos). Foram realizadas análises sensoriais e de condutividade elétrica. Os frutos de cafeeiros localizados em altitudes de 1050 m possuem atributos sensoriais superiores aos de altitudes de 850 m. Os melhores resultados dos atributos sensoriais sabor e aroma do café foram obtidos no sistema de processamento via úmida quando comparado como sistema de processamento via seca (natural). A condutividade elétrica dos grãos de café obtidos no sistema de processamento via úmida foi menor que a obtida no sistema de processamento via seca (natural), o que confere melhor qualidade de bebida. Os métodos de secagem em terreiro suspenso e em terreiro de cimento, ambos com cobertura plástica e se tecnicamente conduzidos, não influenciam nas características sensoriais do café arábica.

Evaluation of the composition effect of harvested coffee in the organoleptic properties of coffee drink / Evaluación del efecto de la composición del café cosechado en las propiedades organolépticas de la bebida de café

Background: The current flourishing of the specialty coffee market has motivated the development of this research on the basis that the harvested coffee fruits are a determining factor in drink quality. Objectives: The aim of this study was to evaluate the effect of the composition of harvested coffee (Coffea arabica L.) regarding the organoleptic quality of the coffee drink for the varieties Caturra and Colombia. Methods: Treatments for the assessed varieties were defined with different percentage compositions of coffee fruits M1 (100R), M2 (80R, 13OV, 7SR), M3 (60R, 26OV, 12SR, 2UR) and the control M4, which included fruits in different ripening stages, ripe (R), overripe (OV), semi-ripe (SR) and unripe (UR), in different proportions in experimental units of 10 kg of harvested coffee. The experimental design envisaged 3 rounds (repetitions) of harvest. The harvested coffee was classified manually according to its ripening stage using a previously developed scale based on colorimetry and recording the degrees Brix of 50 fruits in each ripening stage. The standardized wet processing method was carried out; a Q Grader cupping panel of five members was used for the sensory analysis of the coffee drink. Results: The results showed that for the variety Caturra statistical differences in cup quality between treatments were not found, whereas for the variety Colombia, treatments M1 and M3 showed similar behavior, with statistically significant differences regarding M2 and M4. Finally, the mathematical modeling obtained to predict the cup score depending on the coffee ripening stages composition, counted with coefficients of determination R2 of 0.946 and 0.852 with an error of 1.40 and 1.03% for the varieties Caturra and Colombia, respectively. Conclusions: The model developed with fuzzy logic and validated with information from other farms, presented an error of less than 2% in the estimation of the cup as a function of the ripening stages composition of the coffee varieties Caturra and Colombia.

Antecedentes: El progreso en el mercado de los cafés especiales, ha motivado el desarrollo de la presente investigación tomando como base que los frutos de café cosechados son un factor determinante en la calidad de la bebida. Objetivo: El objetivo del estudio fue la evaluación del efecto de la composición del café (Coffea arabica L.) cosechado respecto a la calidad organoléptica de la bebida para las variedades Caturra y Colombia. Métodos:, se definieron los tratamientos (composiciones en porcentaje) de café cereza M1 (100M), M2 (80M, 13SM, 7P), M3 (60M, 26SM, 12P, 2V) y testigo M4, las cuales contemplan para los estados de maduración maduro (M), sobremaduro (SM), pintón (P) y verde (V) en proporciones diferentes en unidades experimentales de 10 kg de café cereza. El diseño experimental contempló 3 pases (replicas) de cosecha. Una vez cosechado al café se realizó la clasificación manual de los estados de maduración con ayuda de una escala previamente elaborada, así como la verificación objetiva por colorimetría y el registro de los grados Brix para 50 frutos en cada estado de maduración. Se realizó un proceso de beneficio húmedo estandarizado; se utilizó un panel de catación Q Grader de cinco integrantes para el análisis sensorial de la bebida. Un análisis de varianza fue empleado para comparar los resultados y se usó lógica difusa para elaborar un modelo matemático predictivo de la calidad en taza en las dos variedades. Resultados: Los resultados mostraron que para la variedad Caturra no se encontraron diferencias estadísticas de calidad en taza entre los tratamientos, mientras que para variedad Colombia los tratamientos M1 y M3 presentaron igual efecto con diferencias estadísticas significativas respecto a M2 y M4. Finalmente, el modelamiento matemático obtenido para predecir la puntuación de la taza en función de la composición de los estados de maduración del café, contó con coeficientes de determinación R2 de 0,946 y 0,852 con errores de 1,40 y 1,03% en variedad Caturra y variedad Colombia, respectivamente. Conclusiones: El modelo desarrollado con lógica difusa validado con información de otras fincas presentó un error menor al 2% en la estimación de la taza en función de la composición de los estados de maduración del café variedad Caturra y Colombia.

Discrimination of the sensory quality of the Coffea arabica L. (cv. Yellow Bourbon) produced in different altitudes using decision trees obtained by the CHAID method.

BACKGROUND: Knowledge of the sensory profile of coffee quality, associated with genetic and environmental factors, is of utmost importance for the international market, as well as for the productive sector. In this context, the goal of this study was to classify the quality of Coffea arabica L., cv. Yellow Bourbon, according to different scores obtained through sensory evaluations based on the Specialty Coffee Association of America protocol (SCAA), and by means of decision trees resulting from applying the CHAID method (chi-square automatic interaction detection). To that end, we used a database with the sensory characteristics of cv. Yellow Bourbon and the environmental characteristics of the Mantiqueira de Minas region, State of Minas Gerais, Brazil. RESULTS: The method used exhibited promising results regarding accuracy and success rates in order to discriminate coffee sensory quality as a function of the production environment. The results obtained clearly show the effect of the coffee growing environment on the Yellow Bourbon variety, resulting in notable sensory differences in the beverage. CONCLUSION: It was possible to discriminate cv. Yellow Bourbon coffee samples, the sensory evaluations of which resulted in scores of ≥88 points, which are associated with growing environments at altitudes of ≥1200 m. © 2015 Society of Chemical Industry.