Functional Characterization of ent-Copalyl Diphosphate Synthase and Kaurene Synthase Genes from Coffea arabica L.

The biochemical profile of coffee beans translates directly into quality traits, nutraceutical and health promoting properties of the coffee beverage. Ent-kaurene is the ubiquitous precursor for gibberellin biosynthesis in plants, but it also serves as an intermediate in specialized (i.e., secondary) diterpenoid metabolism that leads to a diversity of more than 1,000 different metabolites. Nutraceutical effects on human health attributed to diterpenes include antioxidant, anticarcinogenic, and anti-inflammatory properties. Cafestol (CAF) and kahweol (KAH) are two diterpenes found exclusively in the Coffea genus. Our objective was to identify and functionally characterize genes involved in the central step of ent-kaurene production. We identified 17 putative terpene synthase genes in the transcriptome of Coffea arabica. Two ent-copalyl diphosphate synthase (CaCPS) and three kaurene synthase (CaKS) were selected and manually annotated. Transcript expression profiles of CaCPS1 and CaKS3 best matched the CAF and KAH metabolite profiles in different tissues. CaCPS1 and CaKS3 proteins were heterologously expressed and functionally characterized. CaCPS1 catalyzes the cyclization of geranylgeranyl diphosphate (GGPP) to ent-copalyl diphosphate (ent-CPP), which is converted to ent-kaurene by CaKS3. Knowledge about the central steps of diterpene formation in coffee provides a foundation for future characterization of the subsequent enzymes involved in CAF and KAH biosynthesis.

Indication of the geographical origin of honey using its physicochemical characteristics and multivariate analysis.

Honey from different botanical sources presents a great variability in chemical composition, physical properties, and sensorial attributes. The association between honey qualities and its geographical origin allows the recognition of honey, and beekeepers are economically benefited. The objective of this study was to evaluate the physicochemical characteristics of honey produced in Ortigueira, Brazil and to compare it with the honey produced in the neighboring localities for the request of geographical indication certification. In the 112 honey samples collected between 2010 and 2013 from Ortigueira and the neighboring localities, moisture acidity, pH, hydroxymethyl furfural (HMF), diastase activity (DA), sugars, proline (Pro), electrical conductivity (EC), color absorbance at 635 nm (C635), and Cielab color parameters were evaluated. HMF, reducing sugars (RS), total sugars (TS), proline, and color parameters (L*, a* and b*) were significantly different in Ortigueira 2010 honey seasons. Principal component analysis separated assapeixe (Vernonia sp) and capixingui (Croton floribundus) honeys from wild honeys (polyfloral). In addition, HMF, RS, L*, and lactonic acidity values promoted the separation between assapeixe and capixingui honeys. Ortigueira honey differs significantly from honeys from neighboring locality in pH, proline, HMF, DA, EC, RS, sucrose, TS, free and total acidity, and color parameters (C635, L*, a*, b*). The multivariate analysis applied to variables was efficient to discriminate honeys from different botanical sources and different locals, and is recommended for studies on the geographical indication of honey.

Characterization of Roasted Coffea arabica Species by the Relationship Between Caffeine and Diterpenes Contents

Abstract Commercial roasted and ground coffees are usually blends of Coffea arabica and Coffea canephora. Considering the differences in price and sensory characteristics between these two species, the identification of the presence of each species in commercial blends is of great interest. The aim of this study was to describe typical profiles of caffeine and diterpenes (kahweol and cafestol) contents and the ratios among these compounds to support the characterization of Coffea species in roasted coffees. 32 good cup quality Brazilian C. arabica coffees (from coffee quality contests) produced using different postharvest treatments were studied. All analysis were performed by HPLC. Higher ranges were observed in diterpene contents - kahweol varied from 1.75 to 10.68 g/kg (coefficient of variation of 510%) and cafestol from 1.76 to 9.66 g/kg (449%) - than caffeine, that varied from 5.1 to 16.2 g/kg (coefficient of variation of 218%). Wide ranges of the kahweol/cafestol ratio (0.63 to 2.77) and the caffeine/kahweol ratio (0.84 to 5.15) were also observed. Hence it was proposed the additional use of a new parameter, the ratio of caffeine/sum of diterpenes (kahweol + cafestol) that presents values from 0.54 to 2.39. The results indicated that the combined use of these parameters could be a potential tool for discriminating Coffea species in blends of roasted and ground coffee. It was proposed as potentially indicative of C. arabica: values of kahweol/cafestol ratio above 0.50, associated with caffeine/kahweol ratio lower than 5.50 and caffeine/sum of diterpenes ratio lower than 2.50.

Correlation between the composition of green Arabica coffee beans and the sensory quality of coffee brews.

This research aimed to correlate the composition of green Arabica coffee beans with the sensory quality coffee brews. The chemical composition of green Arabica coffee bean (66 samples) from three coffee quality contests was analyzed by near-infrared spectroscopy. Coffee brews with lower quality scores were correlated with high levels of caffeine, protein, chlorogenic acids and total titratable acidity (TTA) in the green coffee beans. High sucrose/TTA and cafestol/kahweol ratios in the green coffee beans were usually associated with higher scores for the coffee brews. By multivariate analysis techniques, the samples were separated into groups according to production years indicating a strong influence of the environmental conditions on the chemical composition. The profile of the composition of the crude coffee can be indicative of the sensory quality of the coffee brews, relevant information for producers and industry since the green beans are the material used for trading and purchasing coffee.

The typicity of coffees from different terroirs determined by groups of physico-chemical and sensory variables and multiple factor analysis.

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.

CARACTERÍSTICAS FÍSICAS E QUÍMICAS DE CAFÉS TORRADOS E MOÍDOS EXÓTICOS E CONVENCIONAIS / PHYSICAL AND CHEMICAL CHARACTERISTICS OF EXOTIC AND CONVENTIONAL ROASTED AND GROUND COFFEES

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).