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Coffea arabica is the most economically important coffee species worldwide. However, its production is severely limited by diseases such as rust. The mechanisms underlying constitutive defense responses in coffee are still poorly understood, compared with induced defense mechanisms. We aimed to characterize constitutive defense responses of thirteen cultivars of C. arabica. Cultivars were classified under field conditions according to the level of resistance to rust: resistant (R), moderately resistant (MR), and susceptible (S). Based on this classification, the stability of eight reference genes (RGs) was evaluated. The most stable RGs were EF1α, APT1, and 24S. We also evaluated the expression of CaWRKY1, CaPAL1, CaCAD1, and CaPOX1, and activities of PAL, CAD, and POX, which are involved in lignin biosynthesis, and leaf content of total phenolic compounds and lignin. Gene expression and enzymatic activity were not correlated with defense metabolites in the R cultivar group but showed a negative correlation with phenolic compounds in MR cultivars. Cultivar S showed positive correlations of gene expression and enzyme activity with phenolic compounds. These results may assist coffee breeding programs regarding selection of genotypes and in optimization of rust resistance.

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Physiology-based differentiation of SH genes and Hemileia vastatrix races is the principal method employed for the characterization of coffee leaf rust resistance. Based on the gene-for-gene theory, nine major rust resistance genes (SH1-9) have been proposed. However, these genes have not been characterized at the molecular level. Consequently, the lack of molecular data regarding rust resistance genes or candidates is a major bottleneck in coffee breeding. To address this issue, we screened a BAC library with resistance gene analogs (RGAs), identified RGAs, characterized and explored for any SH related candidate genes. Herein, we report the identification and characterization of a gene (gene 11), which shares conserved sequences with other SH genes and displays a characteristic polymorphic allele conferring different resistance phenotypes. Furthermore, comparative analysis of the two RGAs belonging to CC-NBS-LRR revealed more intense diversifying selection in tomato and grape genomes than in coffee. For the first time, the present study has unveiled novel insights into the molecular nature of the SH genes, thereby opening new avenues for coffee rust resistance molecular breeding. The characterized candidate RGA is of particular importance for further biological function analysis in coffee.

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When it comes to the sensory analysis of specialty coffees, it is necessary to discuss the protocol of tests of the Specialty Coffee Association (SCA) and the formation of Q-Graders as reliable parameters in the sensory analysis. However, the training of these Q-Graders and the use of the SCA protocol has generated discussions in the scientific community and demonstrated the importance of talking about the level of professional precision as well as the use of the protocol. This study sought to understand the relation of accuracy and efficiency of the Q-Graders and protocol in the sensory analysis of coffees. Three experiments were carried out to evaluate and test the hypotheses regarding the level of precision in relation to the shift, the number of samples and the judgment abilities of Q-Graders due to the quality of the specialty coffee and nonspecialty coffee. These three experiments were performed by seven Q-Graders in an isolated environment during three consecutive days with 137 specialty coffee samples and 7 nonspecialty coffee samples as defined by the SCA. The results indicate that the Q-Graders present high precision when evaluating excellent and outstanding coffees, as defined by the SCA. In addition, the effect of the shift did not exert fatigue on the Q-Graders. However, evaluation errors were made by the Q-Graders on very good coffee (77.00-80.00 points), which are considered as nonspecialty by the SCA, thus allowing a more in-depth discussion on what would be the boundary between a specialty and nonspecialty coffee. PRACTICAL APPLICATIONS: The article deals with the sensory evaluation process of coffees, and it has great importance to teaching and research institutions in Brazil, the largest producer, largest exporter and the country with the highest concentration of coffee scholars in the world. The article focuses on a new approach and a new way of looking at the sensory evaluation process of coffees, using the methodology of the Specialty Coffee Association to analyze the accuracy and efficiency of the Q-Graders.

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Coffee production is the result of the relationship between local environmental conditions and coffee cultivars that grow in this place. Coffee plants develop original physico-chemical and sensory characteristics that together with the agricultural techniques practiced by growers define the terroir. The objective of this study was to describe the typicity of coffee prepared by coffee growers from seven coffee terroirs in Paraná, Brazil. The terroir categorization was based on the local latitude, longitude, altitude and annual average temperature. Coffee samples were prepared by the coffee growers according to their agricultural techniques. A multiple factor analysis (MFA) was applied to the groups of variables of the green and roasted coffee bean physico-chemical and sensory attributes. The variability in environmental conditions was sufficient to modify the green and roasted coffee bean characteristics and sensory attributes. The terroir description obtained with MFA description compared to that obtained with individual groups of variables was different among terroirs. Roasted coffee variables and sensory attributes caused the greatest differences. The individual use of these groups of variables may result in non-representative descriptions of coffee from different terroirs. Mandaguari and Ivaiporã terroirs were associated with high nitrogenous compounds content, high expansion volume and low density of roasted coffees, and the beverages showed a high turbidity and intense body. Apucarana, São Jerônimo da Serra and Ribeirão do Pinhal terroirs were associated with low lipids content, high density and low volume expansion roasted coffee, and the beverage showed intense coffee and sweet aromas and a low turbidity and body texture. In coffee from the Londrina terroir, medium nitrogenous compounds content and high sucrose and lipids contents were found. Their beverage showed a high turbidity and intense body as well as a grassy green taste and astringency. Coffee from Ribeirão Claro terroir presented high lipids and sucrose contents and low caffeine and phenolic compounds contents, and the main sensory attributes were a coffee aroma and sweet and sour tastes. In conclusion, a terroir formed by environmental conditions and agricultural techniques can produce coffee with a set of physico-chemical and sensory characteristics that define its typicity.

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BACKGROUND: Detailed knowledge of coffee production systems enables optimization of crop management, harvesting and post-harvest techniques. In this study, coffee quality is mapped as a function of coffee variety, altitude and terrain aspect attributes. The work was performed in the Zona da Mata, Minas Gerais, Brazil. RESULTS: A large range of coffee quality grades was observed for the Red Catuai variety. For the Yellow Catuai variety, no quality grades lower than 70 were observed. Regarding the terrain aspect, samples from the southeast-facing slope (SEFS) and the northwest-facing slope (NWFS) exhibited distinct behaviors. The SEFS samples had a greater range of quality grades than did the NWFS samples. The highest grade was obtained from an NWFS point. The lowest quality values and the largest range of grades were observed at lower altitudes. The extracts from the highest-altitude samples did not produce any low-quality coffee. CONCLUSIONS: The production site's position and altitude are the primary variables that influenced the coffee quality. The study area has micro-regions with grades ranging from 80 to 94. These areas have the potential for producing specialty coffees. © 2015 Society of Chemical Industry.

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Espresso coffee beverages prepared from pure origin roasted ground coffees from the major world growing regions (Brazil, Ethiopia, Colombia, India, Mexico, Honduras, Guatemala, Papua New Guinea, Kenya, Cuba, Timor, Mussulo and China) were characterized and compared in terms of their mineral content. Regular consumption of one cup of espresso contributes to a daily mineral intake varying from 0.002% (sodium; Central America) to 8.73% (potassium; Asia). The mineral profiles of the espresso beverages revealed significant inter- and intra-continental differences. South American pure origin coffees are on average richer in the analyzed elements except for calcium, while samples from Central America have generally lower mineral amounts (except for manganese). Manganese displayed significant differences (p<0.05) among the countries of each characterized continent. Intercontinental and inter-country discrimination between the major world coffee producers were achieved by applying canonical discriminant analysis. Manganese and calcium were found to be the best chemical descriptors for origin.

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This paper describes a new method based on a voltammetric electronic tongue (ET) for the recognition of distinctive features in coffee samples. An ET was directly applied to different samples from the main Mexican coffee regions without any pretreatment before the analysis. The resulting electrochemical information was modeled with two different mathematical tools, namely Linear Discriminant Analysis (LDA) and Support Vector Machines (SVM). Growing conditions (i.e., organic or non-organic practices and altitude of crops) were considered for a first classification. LDA results showed an average discrimination rate of 88% ± 6.53% while SVM successfully accomplished an overall accuracy of 96.4% ± 3.50% for the same task. A second classification based on geographical origin of samples was carried out. Results showed an overall accuracy of 87.5% ± 7.79% for LDA and a superior performance of 97.5% ± 3.22% for SVM. Given the complexity of coffee samples, the high accuracy percentages achieved by ET coupled with SVM in both classification problems suggested a potential applicability of ET in the assessment of selected coffee features with a simpler and faster methodology along with a null sample pretreatment. In addition, the proposed method can be applied to authentication assessment while improving cost, time and accuracy of the general procedure.

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O presente trabalho refere-se à pesquisa de dois cafés exóticos comercializados no Brasil: o café Jacu, proveniente do estado de Espírito Santo, e o café Civeta procedente da Indonésia (cujos frutos maduros são ingeridos e "processados" no trato digestivo de animais). Suas características químicas e físicas foram comparadas às de cafés torrados e moídos comerciais brasileiros (Tradicional, Superior ou Premium e Gourmet). Os valores referentes à composição centesimal, teor de cafeína (1,04 a 1,45%) e sólidos solúveis totais (24,50 a 32,23%) de todas as amostras atenderam aos limites preconizados pela legislação brasileira. Os cafés exóticos, Jacu e Civeta, apresentaram os maiores e menores parâmetros de cor, respectivamente (L* = 20,46 e 11,55; h* = 58,13 e 51,06 e C* = 21,00 e 14,85). Os maiores teores (média de 35,21 mg em equivalente de ácido gálico/g amostra) de compostos fenólicos totais foram verificados nos cafés Tradicional e Premium. Os cafés Jacu e Gourmet apresentaram os maiores teores de 5-ACQ (média de 0,65%) e de trigonelina (média 0,63 g/100 g amostra) e os menores teores de ácido nicotínico (média de 0,022 g/100 g amostra). O café Premium continha os maiores teores de açúcar total (1,37 g glicose/100 g amostra) e o café Tradicional mostrou o maior teor de açúcares redutores (0,27 g sacarose/100 g amostra). O café Gourmet apresentou a maior acidez titulável total (171,13 mL NaOH 0,1 N/100 g amostra) e o Premium a menor (121,31 mL NaOH 0,1 N/100 g amostra).

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Considering that illegal admixture of robusta coffee into high-quality arabica coffee is an important task in coffee analysis, we evaluated the use of direct-infusion electrospray ionization-mass spectrometry (ESI-MS) data combined with the partial least-squares (PLS) multivariate calibration technique as a fast way to detect and quantify arabica coffee adulterations by robusta coffee. A total of 16 PLS models were built using ESI± quadrupole time-of-flight (QTOF) and ESI± Fourier transform ion cyclotron resonance (FT-ICR) MS data from hot aqueous extracts of certified coffee samples. The model using the 30 more abundant ions detected by ES+ FT-ICR MS produced the most accurate coffee blend percentage prediction, and thus, it was later successfully employed to predict the blend composition of commercial robusta and arabica coffee. In addition, ESI± FT-ICR MS analysis allowed for the identification of 22 compounds in the arabica coffee and 20 compounds in the robusta coffee, mostly phenolics.

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Cascas de café são fonte de carboidratos e nutrientes que podem ser bioconvertidos em produtos de interesse como enzimas. Lacases são cobre polifenol oxidases que oxidam compostos fenólicos, enquanto reduzem oxigênio molecular à água e; sua baixa especificidade a substratos permite sua aplicação em várias áreas como indústria têxtil, de alimentos e biorremediação. Os objetivos desse trabalho foram avaliar a capacidade de produção de lacase de três linhagens de fungos basidiomicetos (Lentinula edodes U6/1, Pleurotus ostreatus U6/9 e Pleurotus florida U6/10) por fermentação submersa com cascas de café e avaliar o uso de cobre como indutor dessa enzima. A casca de café mostrou ser um bom substrato para produção de lacases e das três linhagens testadas Pleurotus ostreatus (U6/9) foi a mais produtiva (22,5 U mL-1). A melhor fonte de nitrogênio para produção de lacases de Pleurotus ostreatus (U6/9) foi o extrato de levedura na concentração de 9 g/L (20 U mL-1). A adição de 150 μM de CuSO4 resultou na indução significativa na produção de lacases nessa linhagem (21 U mL-1) no 12° dia de cultivo.(AU)

Coffee husks are a source of carbohydrates and nutrients that may be bioconverted into products of interest, such as enzymes. Laccases are copper polyphenol oxidases that oxidize phenolic compounds while reducing molecular oxygen to water. Laccases low specificity to substrates allows its application in several areas such as textiles, food processing and bioremediation industries. The aims of this study were to evaluate the potential to produce laccase from three strains of basidiomycetous fungi (Lentinula edodes U6/1, Pleurotus ostreatus U6/9, and Pleurotus florida U6/10) by submerged fermentation with coffee husks, and to evaluate the use of copper as an inducer of the enzyme. Coffee husk proved to be a good substrate for laccase production, with Pleurotus ostreatus (U6/9) being the most productive strain (22.5 U mL-1). The best source of nitrogen for laccase production of Pleurotus ostreatus (U6/9) was yeast extract 9 g/L (20 U mL-1). The addition of CuSO4 (150 μM) resulted in significant induction of laccase (21 U mL-1) on the 12th day of cultivation.(AU)

Cáscaras de café son fuente de carbohidratos y nutrientes que pueden ser bioconvertidos en productos de interés, tales como enzimas. Lacases son cobre polifenol oxidasas que oxidan compuestos fenólicos, mientras reducen el oxígeno molecular a el agua y; su baja especificidad a sustratos permite su aplicación en diversas áreas, como la industria textil, de alimentos y de biorremediación. Los objetivos de este estudio fueron evaluar la capacidad de producción de lacase de tres linajes de hongos basidiomicetos (Lentinula edodes U6/1, Pleurotus ostreatus U6/9 y Pleurotus florida U6/10) por fermentación sumergida con cáscaras de café, y evaluar el uso del cobre como inductor de esta enzima. La cáscara de café resultó ser un buen sustrato para la producción de lacases y, de las tres linajes probadas, Pleurotus ostreatus (U6/9) fue la más productiva (22,5 U mL-1). La mejor fuente de nitrógeno para la producción de lacases de Pleurotus ostreatus (U6/9) fue el extracto de levadura a una concentración de 9 g L-1 (20 U mL-1). La adición de 150 μM de CuSO4 resultó en la inducción significativa de Cáscaras de café son fuente de carbohidratos y nutrientes que pueden ser bioconvertidos en productos de interés, evadura a una concentración de 9 g L-1 (20 U mL-1). La adición de 150 μM de CuSO4 resultó en la inducción significativa de la producción de lacases en esa linaje (21 U mL-1), en el 12º día de cultivo.(AU)

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Cascas de café são fonte de carboidratos e nutrientes que podem ser bioconvertidos em produtos de interesse como enzimas. Lacases são cobre polifenol oxidases que oxidam compostos fenólicos, enquanto reduzem oxigênio molecular à água e; sua baixa especificidade a substratos permite sua aplicação em várias áreas como indústria têxtil, de alimentos e biorremediação. Os objetivos desse trabalho foram avaliar a capacidade de produção de lacase de três linhagens de fungos basidiomicetos (Lentinula edodes U6/1, Pleurotus ostreatus U6/9 e Pleurotus florida U6/10) por fermentação submersa com cascas de café e avaliar o uso de cobre como indutor dessa enzima. A casca de café mostrou ser um bom substrato para produção de lacases e das três linhagens testadas Pleurotus ostreatus (U6/9) foi a mais produtiva (22,5 U mL-1). A melhor fonte de nitrogênio para produção de lacases de Pleurotus ostreatus (U6/9) foi o extrato de levedura na concentração de 9 g/L (20 U mL-1). A adição de 150 μM de CuSO4 resultou na indução significativa na produção de lacases nessa linhagem (21 U mL-1) no 12° dia de cultivo.

Coffee husks are a source of carbohydrates and nutrients that may be bioconverted into products of interest, such as enzymes. Laccases are copper polyphenol oxidases that oxidize phenolic compounds while reducing molecular oxygen to water. Laccase’s low specificity to substrates allows its application in several areas such as textiles, food processing and bioremediation industries. The aims of this study were to evaluate the potential to produce laccase from three strains of basidiomycetous fungi (Lentinula edodes U6/1, Pleurotus ostreatus U6/9, and Pleurotus florida U6/10) by submerged fermentation with coffee husks, and to evaluate the use of copper as an inducer of the enzyme. Coffee husk proved to be a good substrate for laccase production, with Pleurotus ostreatus (U6/9) being the most productive strain (22.5 U mL-1). The best source of nitrogen for laccase production of Pleurotus ostreatus (U6/9) was yeast extract 9 g/L (20 U mL-1). The addition of CuSO4 (150 μM) resulted in significant induction of laccase (21 U mL-1) on the 12th day of cultivation.

Cáscaras de café son fuente de carbohidratos y nutrientes que pueden ser bioconvertidos en productos de interés, tales como enzimas. Lacases son cobre polifenol oxidasas que oxidan compuestos fenólicos, mientras reducen el oxígeno molecular a el agua y; su baja especificidad a sustratos permite su aplicación en diversas áreas, como la industria textil, de alimentos y de biorremediación. Los objetivos de este estudio fueron evaluar la capacidad de producción de lacase de tres linajes de hongos basidiomicetos (Lentinula edodes U6/1, Pleurotus ostreatus U6/9 y Pleurotus florida U6/10) por fermentación sumergida con cáscaras de café, y evaluar el uso del cobre como inductor de esta enzima. La cáscara de café resultó ser un buen sustrato para la producción de lacases y, de las tres linajes probadas, Pleurotus ostreatus (U6/9) fue la más productiva (22,5 U mL-1). La mejor fuente de nitrógeno para la producción de lacases de Pleurotus ostreatus (U6/9) fue el extracto de levadura a una concentración de 9 g L-1 (20 U mL-1). La adición de 150 μM de CuSO4 resultó en la inducción significativa de Cáscaras de café son fuente de carbohidratos y nutrientes que pueden ser bioconvertidos en productos de interés, evadura a una concentración de 9 g L-1 (20 U mL-1). La adición de 150 μM de CuSO4 resultó en la inducción significativa de la producción de lacases en esa linaje (21 U mL-1), en el 12º día de cultivo.

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Electronic noses (ENs), are used for many applications, but we must emphasize the importance of their application to foodstuffs like coffee. This paper presents a research study about the analysis of Colombian coffee samples for the detection and classification of defects (i.e., using "Cup Tests"), which was conducted at the Almacafé quality control laboratory in Cúcuta, Colombia. The results obtained show that the application of an electronic nose called "A-NOSE", may be used in the coffee industry for the cupping tests. The results show that e-nose technology can be a useful tool for quality control to evaluate the excellence of the Colombian coffee produced by National Federation of Coffee Growers.

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The aim of this work was to optimize the biolistic delivery parameters that affect the DNA delivery and stable expression of marker genes into coffee tissues (Coffea arabica. L. cvs. Caturra and Catuaí). The effect of osmotic preculture length, osmotic concentration of medium, Helium pressure and target distance on transient expression of the uidA gene in coffee leaves and somatic embryos were tested. The highest transient uidA expression was obtained when Caturra (18.3±2.8) and Catuaí (6.8±2.0) leaves and Catuaí embryos (80.0±7.4) were cultured for 5h on Yasuda medium complemented with 0.5M Mannitol +0.5M Sorbitol. The combination of 1100psi and a target distance of 9cm resulted in the highest number of blue spots per Caturra leaf segment (23.6±3.9), whereas for the Catuaí variety the combination of 1100psi and a target distance of six (10.2±1.9) and nine (8.2±1.9) cm gave the highest number of blue spots per leaf segment. The optimized protocol was tested with pCAMBIA 1 301 (uidA gene and the hpt gene), pCAMBIA 1 305.2 (uidA version GUSPlus ™ and the hpt gene) and pCAMBIA 1 301-BAR (uidA gene and the bar gene). The highest number of blue spots was obtained when Caturra (54.6±5.7) and Catuaí (28.9±4.3) leaves were bombarded with pCAMBIA 1 305.2. Selection of bombarded coffee tissues with 100mg/l hygromicyn caused the oxidation of tissues. Rev. Biol. Trop. 57 (Suppl. 1): 151-160. Epub 2009 November 30.

La presente investigación tuvo como objetivo optimizar los parámetros que afectan la incorporación y expresión de genes marcadores mediante biobalística en segmentos de hoja y embriones somáticos de café (Coffea arabica. L. cvs. Caturra y Catuaí). La mayor expresión transitoria del gen uidA en segmentos de hoja de Caturra (18.3±2.8) y Catuaí (6.8±2.0) y embriones somáticos de Catuaí (80.0±7.4) se obtuvo al cultivar los explantes por cinco horas previo al bombardeo en el medio Yasuda complementado con 0.5M mannitol+0.5M sorbitol. Asimismo, se obtuvo una mayor expresión transitoria del gen uidA al bombardear los segmentos de hoja de Caturra y Catuaí y embriones somáticos de Catuaí con una presión de helio de 1 100psi y una distancia de bombardeo de 6 o 9 cm.

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In this study we show that the continental origin of coffee can be inferred on the basis of coupling the isotope ratios of several elements determined in green beans. The combination of the isotopic fingerprints of carbon, nitrogen and boron, used as integrated proxies for environmental conditions and agricultural practices, allows discrimination among the three continental areas producing coffee (Africa, Asia and America). In these continents there are countries producing 'specialty coffees', highly rated on the market that are sometimes mislabeled further on along the export-sale chain or mixed with cheaper coffees produced in other regions. By means of principal component analysis we were successful in identifying the continental origin of 88% of the samples analyzed. An intra-continent discrimination has not been possible at this stage of the study, but is planned in future work. Nonetheless, the approach using stable isotope ratios seems quite promising, and future development of this research is also discussed.

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It is well known that proteins and peptides play an important role in the flavour of roasted coffee, but little is reported in the literature about their characterization. In view of the potential of matrix-assisted laser desorption/ionization mass spectrometry in the analysis of proteins in complex mixtures, two varieties of coffee green beans, Arabicas and Robustas, were analyzed by this technique, in order to obtain fingerprints of their native proteins. Differences were observed between Arabicas and Robustas green beans, and cluster analysis allows differentiation of samples of the same variety from different plantations.

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The objective of this research was to demonstrate the feasibility of this method to differentiate the geographical growing regions of coffee beans. Elemental analysis (K, Mg, Ca, Na, Al, V, Cr, Mn, Fe, Co, Ni, Cu, Zn, Mo, S, Cd, Pb, and P) of coffee bean samples was performed using ICPAES. There were 160 coffee samples analyzed from the three major coffee-growing regions: Indonesia, East Africa, and Central/South America. A computational evaluation of the data sets was carried out using statistical pattern recognition methods including principal component analysis, discriminant function analysis, and neural network modeling. This paper reports the development of a method combining elemental analysis and classification techniques that may be widely applied to the determination of the geographical origin of foods.

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Coffee is basically consumed for the pleasure given by its taste and aroma, that is, the quality and acceptance of the coffee beverage are directly related to its sensorial characteristics. Thus, nowadays coffee quality is basically evaluated by sensorial analysis. However, together with this kind of analysis, it should be important to have available more objective chemical methods to assess coffee quality. One possible approach could be based on the analysis of chlorogenic acids (CGA), since they are considered precursors of coffee flavour and pigments during roasting. In the present work, high performance liquid chromatography (HPLC) analysis of chlorogenic acids was applied to six different Brazilian arabica green coffee samples which were previously characterised by sensorial analysis. The results showed the potential to correlate the chemical data, evaluated by the Principal Components Analysis (PCA) statistical method, with sensorial analysis in order to discriminate the quality of the samples. It was observed that the 3,4-dicaffeoylquinic (3,4-diCQA) and 3,5-dicaffeoylquinic (3,5-diCQA) isomers are very important for grouping the coffees into good and bad samples.

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