Coffee Science (E-Journal)
Not a member yet
873 research outputs found
Sort by
Sensory and chemical analyses of spontaneously fermented coffees
Get PDFCoffee fermentation has emerged as an innovative post-harvest process in recent years. The effectiveness of this process is in conferring sensory notes to the coffee that would please the consumer and allow for the positive differentiation of the coffees. This is achieved by monitoring the different parameters of the procedure of coffee fermentation. In this regard, the present study aimed to conduct a natural fermentation of the coffee fruit for up to 96 hours followed by the sensory (sensory characteristics for aroma, flavor, acidity, body and overall score of the 0 to 100) and chemical analyses (bioactive compounds, volatiles, organics, and fatty acids) to evaluate the influence of fermentation on sensory quality and on chemical compounds. The coffee (Coffeea arabica L.) samples for the study were collected from Presidente Olegário – MG (Harvest 2018/19) in the cerrado of Minas Gerais. The effects of fermentation and fermentation duration on the sensory quality and chemistry of coffee were evaluated. It was observed that after 48 h of fermentation, significant sensorial differentiation occurs, including an increase of the approximately two points in the final grade. In addition, time was revealed as the most relevant factor in the chemical analyses for the categorization of samples into different groups. Accordingly, it was concluded since coffees with subjected to 48, 72, and 96 h of fermentation got higher final grades, higher levels of palmitic fatty acid and characteristic compounds of fermented coffees (1,3-dioxolane 2,4,5-trimethyl, 2-furan methanol acetate, and butanoic acid) checking out the coffees wine-like notes and sweet notes to the beverage.
Key words: Coffeea arabica L.; sensory evaluation; volatile composition
New vegetation index for monitoring coffee rust using sentinel-2 multispectral imagery
Get PDFCoffee Rust (Hemileia vastatrix) is considered the primary coffee disease in the world. The pathogenic fungus can find favorable environmental conditions in different countries, constantly threatening coffee producers. The previous detection of the incidence of coffee rust in a region is crucial because it provides an overview of the disease’s progress aiding in coffee plantations management. The objective of this work was the development of a vegetation index for remote monitoring of coffee rust infestation. Using satellite images from the MSI/Sentinel-2 collection, the Machine Learning classifier algorithm - Random Forest, and the cloud processing platform - Google Earth Engine, the most sensitives bands in coffee rust detection were determined, namely B4 (Red), B7 (Red Edge 3) and B8A (Red Edge 4). Thus, the Triangular Vegetation Index method was used to create a new vegetative index for remote detection of coffee rust infestation on a regional scale, named Coffee Rust Detection Index (CRDI). A linear regression model was created to estimate rust infestation based on the performance of the new index. The model presented a coefficient of determination (R²) of 62.5%, and a root mean square error (RMSE) of 0.107. In addition, a comparison analysis of the new index with eight other vegetative indices commonly used in the literature was carried out. The CRDI obtained the best performance in coffee rust detection among the others. This study shows that the new index CRDI has the robustness and general capacity to be used in monitoring coffee rust infestation on a regional scale.
Key words: Hemileia vastatrix; disease monitoring; triangular vegetation index method; google earth engine
Coffee plant diseases affected by nutritional balance
Get PDFIn recent years, sustainability has become a priority in agricultural production programs throughout Brazilian territory due to the need to ensure food security and environmental quality. Diseases continue to be a factor limiting sustainable agricultural production, due to the great need for chemical defenses for their control. Thus, it is indispensable to make use of alternative management techniques to reduce the use of such chemical defenses and to increase resistance of plants to diseases. It is known that mineral nutrients affect plant resistance to diseases, and effective physical and biochemical response of plants to pathogens is determined by adequate concentrations of mineral elements in the plant tissues. This review presents the most recent information related to the mode of action of the nutrients in the host-pathogen interaction and individual action in the control of plant diseases with the use of essential nutrients, as well as other elements considered beneficial, such as Si. It also reports on the use of some of these mineral nutrients in control of the main diseases of the coffee plant that occur in Brazil, especially rust, cercosporiosis or brown eye spot, phoma leaf spot, and bacterial blight. In addition, contradictory and satisfactory results are found in the literature on the use of mineral nutrients in control of different diseases, including coffee diseases.
Key words: Coffee growing; nutrients; management; pathogens; plant physiology
Organomineral fertilizer in coffee plant (Coffea arabica L.): Fertilizer levels and application times
Get PDFCoffee (Coffea arábica L.) is a fundamental agricultural commodity in the Brazilian economy, demanding a high amount of nutrients for good vegetative development and productivity. The tested hypothesis was that the use of the organomineral fertilizer promotes coffee production and development due to the greater availability of N, P, and K in the soil. The objective of this study was: (i) to monitor the use efficiency of the organomineral fertilizer rates; (ii) to determine the coffee production and development with the organomineral application. A study was developed with applications of four organomineral rates (75%, 100%, 125%, and 150% of the recommended P2O5 rate), three forms of parceling (one, two, and three applications of the organomineral fertilizer), and one control (100% mineral). Yield, soil, leaves, and plant development were monitored. Results showed that organomineral presented a win-win scenario with adequate disposal of residues and sources of nutrients in agriculture promoting the coffee yield from 49.5 (mineral fertilizers) to 53.5 sc ha-1 (100% of P2O5 in organomineral). The plant height, the diameter of the stem, and the canopy presented a quadratic response to organomineral rates with optimal rates fitted at 127; 140; and 140 %, respectively, but there was no direct effect on yield. The split organomineral applications promoted the contents of P and K in the soil, mainly when associated with higher organomineral rates. The K efficiency use was increased with organomineral application indicating the K was used with more efficiency.
Key words: Fertilization; vegetative development; fertilizers; nutrients
Initial growth of Coffea canephora: Simulation of organomineral system and Limnoperna fortunei as soil improvement
Get PDFThe use of residues can be an alternative to mineral fertilization. Manures, sources of nutrients and organic matter, are successfully used in family farming. Another residue that can be used for soil acidity amelioration is the shell of the golden mussel (Limnoperna fortunei), which is rich in CaCO3. This work evaluated the contribution of ground golden mussel shells (GMS) in combination with cattle (CTM) and sheep (SHM) manure to the initial growth of Conilon coffee in an acidic sandy soil. The experiment was carried out in protected cultivation in pots (30 kg) with two Conilon coffee cultivars. The treatments consisted of two doses of CTM (0 or 67 t ha-1) and four doses of GMS (0, 1, 2 and 3 t ha-1), with three replications. Each treatment was incorporated into the soil before the introduction of the seedlings in the experimental units, and 60 days later, a dose of SHM was applied on the soil surface (20 t ha-1).After 180 days, the soil fertility was analysed, and the seedling height, stem diameter, root volume and fresh and dry mass of the aerial parts and roots were measured. Furthermore, the Dickson Quality Index (DQI) was calculated. Both the sheep and the bovine manure increased the pH, the contents of P, MO, K+, Ca2+, and Mg2+, and the cations exchange capacity (CEC) of the soil. The addition of GMS increased the pH and the Ca2+ content while reducing the potential acidity of the soil. A pH above 6.0 reduced the levels of micronutrients in the soil. The use of CTM and SHM shows promise in the initialgrowth of coffee seedlings (height - H, FMAP, fresh and dry mass of the aerial parts - DMAP, FAR, fresh and dry mass of the root system – DMR diameter, RV root volume and Dickson Quality Index ). Ipiranga 501 surpassed Verdebras G35 in aerial fresh and dry mass, root volume and IQD, with or without the addition of 3 t ha-1 of ground GMS.
Key-words: Cattle manure; Sheep manure; Golden mussel; Robusta coffee; Conilon coffee
Phosphorus fixation and its relationship with soils chemical properties of the coffee zone of Huila, Colombia
Get PDFAdsorption is one of the critical processes in phosphorus (P) availability in plants. In the coffee crop (Coffea arabica), the highest dose of P is supplied in the vegetative phase, so its management is fundamental to guarantee the optimum growth of plants. The aim of this work was to determine the P fixation capacity and its relationship with the soil chemical properties of the Huila coffee zone, Colombian department, with the largest area planted with coffee. The adsorption isotherms were obtained by equilibrating the soil with 30mL of KH2PO4 solution dissolved in a 0.01M CaCl2.2H2O, containing concentrations of P between 50 and 4.200 mg kg-1. The P adsorption was measured for 60 soil samples collected from the five main cartographic units of the department: Campoalegre, El Recreo, La Cristalina, Saladoblanco, and San Simón. The data fitted to the linear and nonlinear Langmuir model forms. It was found that the soils of the region have a variable P fixation capacity, with values of q (adsorption at 0.2 mg L-1 in solution) between 8 and 1330 mg kg-1 and b (maximum adsorption capacity) from 117 to 3916 mg kg-1, without finding an association with the evaluated soil units. A correlation of q and b was found between Al3+, Al3+ saturation, pH, Ca2+ and Mg2+, and base saturation.
Key words: Langmuir isotherms; phosphorus adsorption; soil acidity; soil cartographic unit
Geographic scope of the global value chain for Indonesian coffee
Get PDFThrough the global value chain (GVC), the coffee sector is expected to meet one of the UN’s targets in the SDGs, which is to increase exports from developing countries to help them integrate into the multilateral trading system and benefit from it. Understanding the geographic scope of Indonesian coffee is essential, given that coffee is a pivotal global commodity for Indonesian coffee development. This study aims to analyze the geographic scope of Indonesia’s green coffee beans trade and the key factors that determine the flow of this trade. The analytical approach employed is Gereffi’s GVC analysis and Gravity Model. The panel data analysis uses bilateral coffee trade flows of 13 trading partners from 2002 to 2021. Analysis shows Indonesia exports most of its coffee to Global North countries, which also function as lead firms. Indonesia’s coffee GVC is concentrated at the upstream stages, while complex processing activities occur in advanced countries. According to the gravity model, the significant variables that affect Indonesia’s coffee trade flow are the importing country’s real GDP per capita, the importing country’s population, Indonesia’s real exchange rate against the local currency, Indonesia’s coffee competitiveness, and the non-tariff measurements for coffee. The potential countries to increase the Indonesian coffee trade are existing coffee markets.
Key words: Coffee export; gravity model; green coffee bean; trade flow; trade potential
Identification of soil physicochemical, land suitability, and its relationship to Coffee arabica yielding based on plant age groups
Get PDFThe low yield of Coffee arabica could be caused by several factors such as low soil characteristics and depending on the plant age. This study aimed: (1) to obtain information on soil physicochemical characteristics and productivity of Coffee arabica in different age groups, (2) to evaluate the land suitability for C. arabica plants and obtain the relationship between land characteristics and C. arabica yield. This study was conducted on C. arabica smallholders in Tarutung Subdistrict, North Tapanuli District, North Sumatra, Indonesia from October 2021 to February 2022 and used a descriptive-analytic method. Overlay maps of soil type, altitude, and slope to obtain a Soil Map Unit (SMU) then surveyed for the plant age distribution of 6-10 and 11-15 years. Land characteristics were analyzed by matching method, multiple linear regression, and t-test of yielding characters using IBM SPSS software. The results showed that the soil physicochemical characteristics were classified as low, the soil texture was slightly sticky, and higher productivity was found at 11-15 years old. It was found that the potential and actual land suitability classes were not suitable (N) in SMU-1 at 11-15 years, and other SMUs were classified as marginally suitable (S3). Altitude, silt, and clay fractions significantly affect the productivity of C. arabica plants at 6-10 years. However, an increase in altitude, cation exchange capacity, base saturation, and organic-C could be increased the productivity of C. arabica at 6-10 years.
Key words: Land suitability; overlay; physicochemical; productivity; soil map unit
Regeneration and development of Coffea arabica L. plants through indirect somatic embryogenesis
Get PDFMicropropagation of AS2K clones Arabica coffee (Coffea arabica L.) was attempted through indirect somatic embryogenesis by using ten different parts of the leaf such as shoot, first leaf base, second leaf base, third leaf base, first leaf middle, second leaf middle, third leaf middle, first leaf tip, second leaf tip, and third leaf tip. The influence of the part of leaf explants, combination of plant growth regulator (PGRs) in the induction of embryogenic callus and regeneration of embryo somatic were studied. Furthermore, the various protocols to induce regeneration of somatic embryo into plantlet through different step of subculture and the use of various germination medium were demonstrated. The morphological characteristics and histological analysis of embryogenic callus and embryo development were observed. In this experiment, it was observed that the M5 medium supplemented with 1 mg/L 2,4-D, 1 mg/L BAP and 4 mg/L 2-ip was closely associated with third leaf tip explants for induction of embryogenic callus. The maximum number of globular, heart-shape, torpedo and cotyledones (18, 4, 12, 4, respectively) were achieved on ERM6 medium containing 2 mg/L BAP without activated charcoal on 90th day for regeneration of embryo somatic. The length of roots is the most influence paramater on plantlet regeneration, and the 17th protocol which used B medium, large embryos and twice phase of subculture from liquid medium to solid medium is the best protocol for plantlet regeneration. The protocol developed could be useful highly for large-scale micropropagation in these commercially important Arabica coffee clones.
Key words: Indirect somatic embryogenesis; 24-D; BAP; histology; anatomy
Physical and sensorial quality of arabica coffee cultivars submitted to two types of post-harvesting processing
Get PDFThe growing demand for better quality coffees has driven changes in the coffee production chain, mainly through the adoption of new technologies and management. Thus, this work was carried out aiming to evaluate the physical and sensorial quality of Arabica coffee cultivars, submitted to natural and pulped post-harvesting processing. The experiment was carried out following a randomized block design with three replications, in a split-plot scheme, with the plots consisting of five cultivars (Catucaí 2 SL, Catucaí 24/137, Catuaí IAC 44, Arara and Acauã); and the subplots by two processes, pulped and natural cherry. The harvest was carried out manually, harvesting the cherry fruits (ripe) in a sieve. The coffees were processed by the natural and pulped cherry methods. Drying was carried out on a covered suspended terrace, until the grains reached 11% ± 1 moisture (wet basis, bu). The following evaluations were carried out: sensorial analysis of the beverage according to the SCAA methodology, analysis of grain sieves according to the Official BrazilianCoffee Classification Protocol. The results show that all evaluated cultivars have a great potential for the production of specialty coffees in that studied environment. Differences were observed between cultivars both in the sensory quality of the beverage and in the grain size. Cultivar Arara presents a general average of final beverage grade higher than the other cultivars.
Key-words: Arabica coffee; Coffee sieve size; natural processing; pulped cherries; specialty coffee