Coffee Science (E-Journal)
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Physicochemical and sensory analysis of coffee: A determination in different parts of the plant
Get PDFThe 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.
Key-words: Coffee growing; exposure face; sensory analysis-SCAA; Coffea arabica L.; soluble solids
Characterization in populations of Coffea arabica L. for resistance to CBD using molecular markers
Get PDFCoffee berry disease (CBD) is caused by the fungus Colletotrichum kahawae Waller and Bridge. This disease is restricted to the African continent, where it can cause production losses of more than 80% when susceptible varieties are used or when the indicated chemical control is not carried out. For this reason, since 1970, Cenicafé has developed lines resistant to this disease in the absence of the pathogen, a process that has been favored by the discovery and validation of microsatellite markers associated with the Ck-1 gene for resistance to CBD. In this research, 12 populations of Coffea arabica were characterized for their resistance to CBD using the molecular markers Sat235, Sat207 and FR34-6CTG. The molecular markers allowed us to identify that the same allelic form of resistance to CBD is present in lines derived from Timor Hybrid CIFC 1343 (HdT CIFC 1343). Furthermore, the allelic form of resistance associated with the three molecular markers was identified in one line derived from Coffea canephora. In lines derived from Caturra x HdT CIFC 1343 it was evident that, when the plants present the allelic forms of resistance identified by the molecular markers, high percentages of hypocotyls resistant to different isolates of C. kahawae are observed in the progeny.
Key words: CBD; Coffea spp; resistance genes; marker-assisted selection
Review of the contributions of some statistical methodologies related to the quality of specialty coffee
Get PDFSensory perception involves psychological issues and cognitive skills. The greatest individual differences are observed in sensory experiments, since tasters’ senses assign positive or negative attributes to a product, which are numerically represented by means of a hedonic scale. Thus, when considering statistical methodologies to evaluate the results, the question becomes a challenge to answer because its application requires presumptions that are not always met. In addition, answering a single objective limits the search for the state of the art, contextualized in the exploration of other results that arises from new applied methodologies. Based on this argument, this study aims to present a methodological review that presents the results and contributions of different statistical techniques, addressed by mixing distributions, resampling techniques to build indices robust to outliers, machine learning to I'm prove multivariate classifiers and visualization techniques of the data. These are derived from a single database, which references analyses of the quality of specialty coffees with denomination of known origins that are evaluated by heterogeneous groups of tasters. Based on the knowledge base of the researchers and a review of the literature, the aforementioned methodological procedures are applied, and their advantages and aggregate results are compared to the understanding of the behavioral attitudes that lead to the distinction of the quality of the coffees evaluated.
Key words: Taster; attributes; data mining; models; machine learnin
Analysis of shape features by applying gain ratio and machine learning for coffee bean classification
Get PDFCoffee is one of the daily consumed beverages in many countries. It is yielded from coffee beans, which have proceeded through several processes. Several common coffee beans have been produced in Indonesia, such as Arabica, Robusta, Liberica, and Excelsa. Nevertheless, many coffee fanatics are unable to distinguish the various coffee bean types visually based on those shapes. Accordingly, it is necessary to classify the types of coffee beans. The work applied training and testing steps. Both involved ROI detection, pre-processing, segmentation, feature extraction, selection, and classification. Image processing was used in ROI detection, pre-processing, and segmentation to simplify the procedure and separate the coffee bean from the background. The feature extraction produced 14 shape features to distinguish the coffee bean’s class, but the proposed method’s performance has yet to reach the optimal result. The gain ratio was used to reduce the features; hence, only 4 features were selected, including aspect ratio, eccentricity, equivalent diameter, and area. These features were utilized as input data for classification using Naive Bayes, Artificial Neural Network (ANN), Support Vector Machine (SVM), C4.5, and decision tree. The proposed method used 4 features and a decision tree classifier. The local dataset has 400 coffee bean photos in four classes of 100 images each. The photos were divided for training and testing using k-fold 10 cross-validation. The accuracy evaluation parameter reached 0.995.
Key words: Coffee beans; otsu method; features reduction; cross-validation; decision tree
Can season and intercropping Conilon coffee favor predatory ant species?
Get PDFConilon coffee (Coffea canephora Pierre ex A. Froehner) is an important crop in Brazil, and this culture is widely grown in Espírito Santo State. Intercropping this species has been adopted for better use, profitability, and sustainability of the cultivated area. Intercropping provides higher shading and may favor edaphic fauna that plays an important ecological function in the soil. Ants are part of the edaphic meso - and macrofauna, considered ecosystem engineers and actively participate in pest predation. The goal of the study was to evaluate predatory ant richness in Conilon coffee in monoculture and intercropped with teak or Australian cedar. Furthermore, the influence of these crops on the richness of predator ant communities in the dry (winter) and rainy (summer) seasons was analyzed. The study was conducted in the municipality of Sooretama, northern Espírito Santo State (Brazil) using pitfall soil traps. Ant communities were analyzed with their distribution in trophic guilds. The richness of predatory ants (predatory and generalist omnivore predatory ant species) was studied in Conilon coffee in monoculture and intercropped with teak (Tectona grandis L.f.) and with Australian cedar (Toona ciliata M. Roemer), in the dry (winter) and wet (summer) seasons. A total of 49 ant species were collected, 29 predatory and 15 generalist omnivore predatory ant species were identified, and 16 ant species were recorded for the first time in Espírito Santo State. Conilon coffee cropping systems did not affect the richness of predatory or generalist omnivore predatory ant species, however, summer favored the occurrence of total predatory ants (generalist omnivore + predators); intercropping Conilon coffee did not favor predatory ants. The presence of predatory species is important for natural pest control, consequently improving crop sustainability. However, new research must be done to evaluate other Conilon coffee intercropping for a longer period.
Key words: Biological control; Coffea canephora; Edaphic fauna; Toona ciliata; Tectona grandis
Descriptive sensory tests for evaluating Coffea arabica: A systematic review
Get PDFCoffee 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.
Key words: Coffea arabica; coffee; sensory descriptive analyses; systematic review
Nutrient content and cutting anatomy can affect the production of Conilon clonal plantlets
Get PDFCutting is the main vegetative propagation method used to produce Coffea canephora plantlets. In this method, the nutritional quality of the vegetative propagule (stem cuttings) is one of the determining factors for the rooting speed and the final quality of the plantlets. Thus, the objective in this study was to verify possible variations in nutrient content and anatomical characteristics in cuttings collected at different times of the year and their relationship with the production of Coffea canephora clonal plantlets. The study was divided into two phases: 1) Nutritional composition and anatomy of C. canephora cuttings grown at different times; 2) Production of C. canephora seedlings under greenhouse conditions. The treatments consisted of cuttings collection and plantlets production at different times of the year: January, May and September 2017. We observed that there is seasonal variation for the content of N, P, K and Mg; and anatomical changes in xylem, phloem and vascular cylinder thickness in cuttings harvested at different times of the year. We conclude that although nutritional and anatomical aspects of the vegetative propagule may result in different vegetative growth rates of C. canephora clonal plantlets, this result is more dependent on the management of the nursery environment conditions, especially temperature and relative air humidity.
Key words: Coffea canephora; cutting nutrition; clonal plantlet; vegetatif growth; physiological quality
Yield and beverage quality of thirty-one Coffea canephora clones shaded by Hevea brasiliensis
Get PDF Coffea canephora is predominantly grown in monoculture in Brazil, particularly in areas with full sunlight. However, adverse climatic conditions, such as prolonged droughts and rising temperatures, are increasingly affecting the major coffee-producing regions. The objective of this study was to evaluate the influence of rubber tree shading on the productivity and cup quality of 31 clones of C. canephora, cultivated in the northern region of Espírito Santo state. Thirty-one C. canephora clones were evaluated under three shading conditions: full sunlight, morning shade, and afternoon shade. The parameters analyzed included thousand-seed weight, quantity of beneficiated green coffee beans, yield, the number of ripe fruits required to produce a 60 kg bag of green coffee beans, and sensory analysis. The results showed that coffee clones grown in afternoon shade had a reduced yield per plant but produced heavier beans and better beverage quality. Clones 02, 03, 16, 19, 31, 99, 120, and 143 stood out with the highest yields, while clones 46 and 106 exhibited the lowest. Additionally, the yield analysis revealed that the production of green grains was significantly affected by the growing conditions, with the most productive clones thriving under full sunlight. The afternoon shade may reduce yield, but it improves grain weight and beverage quality, making it a viable strategy for C. canephora clones. Selection should prioritize yield and quality in shaded environments.
Key words: Consortium; conilon; rubber tree
Evaluation of Lactobacillus Coagulans in the design of coffee-based probiotic beverages by using different preparation methods
Get PDFThe purpose of the presented work was to assess the viability of microcapsules containing Bacillus coagulans. These microcapsules were produced through spray drying and employed two different combinations of wall materials. The evaluation was carried out within the context of creating coffee-based beverages using nine distinct preparation methods. Various characteristics of the microcapsules were measured, including solubility, wettability, hygroscopicity, moisture content, and water activity. Sensory analysis was used to determine the proportion of probiotic incorporation in the roasted and ground coffee. Moreover, the viability and count of probiotics were quantified in the nine preparations, both in cold and hot water. Among the preparation methods, the Chemex approach demonstrated enhanced viability when utilized for hot water preparation, while the Cold Tower method excelled in cold water scenarios. The outcomes of the study underscore the considerable potential of Bacillus coagulans in developing coffee-based probiotic beverages. These beverages exhibit noteworthy chemical, sensory, and functional stability.
Key words: Coffee extract; Cold coffee; Functionality; Microencapsulation
Factors affecting coffee farmers’ production in Jimma Zone, Southwest Ethiopia
Get PDFCoffee yield has good potential in the welfare capabilities of growers in coffee cultivating in Ethiopia in general and particularly in Jimma zone, southwest Ethiopia. Therefore, this study attempts to investigate the factors affecting coffee production in Jimma Zone, Southwest Ethiopia, using cross-sectional field survey data collected from 204 sample coffee growers in the 2023 main growing season. Primary and secondary data were collected in this study. Descriptive and binary logistic regression methods were employed for the data analysis. The results of binary logistic regression analysis showed that age, education status, off-farm activity, landholding, livestock holding, soil fertility, fertilizer use, use of credit, access to extension service, provision of improved seed, access to market information, access to infrastructure, distance to the nearest market and distance to the nearest road were the factors significantly influencing coffee production. Overall, the findings indicate that to enhance and sustain coffee yield in the study area, improved coffee varieties and agronomic practices can be better options to expand coffee yield. Therefore, the concerned bodies should pay considerable attention to coffee production, which is a crucial base for driving food security. The summary of coffee production by policymakers could help to achieve improved living standards for the people in the Jimma Zone.
Key words: Coffee production; Ethiopia; Jimma zone; coffee varieties; food security