scholarly journals ENDOCARP ANALYSIS OF A TRADITIONAL VARIETY OF COLOMBIAN COFFEE

2019 ◽  
Vol 14 (2) ◽  
pp. 206
Author(s):  
MILTON MUÑOZ ◽  
MANUEL ROA ◽  
RODRIGO CORREA
Keyword(s):  
Mass Loss ◽  
Diffusion Coefficients ◽  
Optimization Methods ◽  
Second Law ◽  
Infrared Analysis ◽  
Coffee Bean ◽  
Dehydration Process ◽  
Traditional Variety ◽  
Coffee Beans ◽  
Hemicellulose Degradation

<p> This article presents the main results of thermal analytical and drying tests applied to the endocarp of coffee bean samples, in order to analyze their influence on the coffee dehydration process. An infrared analysis, as well as TGA, DTGA and DSC tests, were applied to the parchment of a sample of Castilla variety coffee beans and later compared with similar tests performed on coffee beans of the same variety, upon parchment removal. For analytical tests, the main thermogravimetric transitions are reported up to a temperature of 1000 °C. From thermograms, four temperature range were identified for parchment, with their respective mass loss: 33-33.7°C, 9.48%; 33.7-251.2°C, 16.23%; 251.2-358°C, 47.48%; and 358-800°C, 15.52%. The greatest mass loss was due to cellulose and hemicellulose degradation. The study was complemented by drying experiments on samples of beans with and without parchment. The diffusion coefficients were found using Fick’s second law and metaheuristic optimization methods (global optimization). On average, the diffusion coefficient of grains without endocarp is 46% greater than that of beans dried with the parchment. Coffee beans with parchment took, on average, 50% more time to reaching moisture levels of 12% (on dry basis). The results are considered important for the projection and design of new coffee drying systems and their automatic control. </p>

scholarly journals Controlled irrigation and nitrogen, phosphorous and potassium fertilization affect the biochemical composition and quality of Arabica coffee beans

2016 ◽  
Vol 155 (6) ◽  
pp. 902-918 ◽  
Author(s):  
F. VINECKY ◽  
F. DAVRIEUX ◽  
A. C. MERA ◽  
G. S. C. ALVES ◽  
G. LAVAGNINI ◽  
...  
Keyword(s):  
Biochemical Composition ◽  
Near Infrared ◽  
Infrared Analysis ◽  
Coffee Bean ◽  
Dry Period ◽  
Continuous Irrigation ◽  
Biochemical Compounds ◽  
Coffee Beans ◽  
Controlled Irrigation ◽  
First Time

SUMMARYControlled irrigation during the dry period associated with adequate nitrogen (N), phosphorous (P) and potassium (K) fertilization led to the accumulation of biochemical compounds in coffee beans considered as positive precursors of beverage quality. Adult plants of coffee (Coffea arabica ‘Rubi’) were cultivated using different water regimes (WR) and fertilization conditions under the dry climate of the Brazilian Cerrado. Coffee-bean physical characteristics were evaluated as well as biochemical composition by near-infrared analysis. The K treatment mostly affected bean biochemistry, lipid and chlorogenic acid (CGA) contents, which increased with increasing amounts of fertilizer. Caffeine contents increased with higher amounts of N, but no significant effects of P treatment on bean biochemical composition were observed. Sucrose and total lipid contents always appeared higher in beans of non-irrigated plants than those beans from plants grown with continuous irrigation. In contrast, caffeine and CGA contents were higher in beans of irrigated as compared with non-irrigated plants. For the first time, the current results showed that controlled management of irrigation during the dry period associated with reasonable NPK fertilization led to the accumulation of biochemical compounds in coffee beans considered as positive precursors of beverage quality.

scholarly journals Comparative analysis of drying coffee beans using microwave and conventional oven

2019 ◽  
pp. 100-108
Author(s):  
Milton Javier Muñoz-Neira ◽  
Manuel Fernando Roa-Ardila ◽  
Carlos Rodrigo Correa-Celi
Keyword(s):  
Diffusion Coefficient ◽  
Diffusion Coefficients ◽  
Microwave Cavity ◽  
Second Law ◽  
Uniform Temperature ◽  
Coffee Beans ◽  
Electric Oven ◽  
Temperature Controlled ◽  
And Diffusion ◽  
Conventional Oven

This article reports a comparative study of experimental results obtained during the drying of Castilla-variety coffee beans from Santander, Colombia. They were performed by two means: thermal and electromagnetic radiation. Twenty experiments were carried out, ten tests in a microwave cavity at 2,450 MHz-1,080W, and ten tests using a conventional electric oven with temperature controlled at 50±2oC. Experiments were made using samples of coffee beans with parchment, without parchment, and of the only-parchment. For each sample, dimensionless moisture ratio and diffusion coefficients were determined, according to the second law of Fick. We found that the diffusion coefficient of the samples dried in a microwave cavity was twenty-two times higher than the diffusion coefficient of samples dried with thermal radiation. Likewise, it was observed that samples in conventional oven showed a uniform temperature, in contrast with those heated by microwave radiation. Such results are useful for designing hybrid systems for drying coffee beans.

Analisis Skrining Fitokimia dan Aktivitas Antioksidan Ekstrakk Biji Sangrai Kopi Robusta (Coffea canephora) dari Tanaman Hasil Pemupukan Organik dan Anorganik

2021 ◽  
Vol 3 (2) ◽  
Author(s):  
Farah Aida Qotrun Nada ◽  
Tintrim Rahayu ◽  
Ari Hayati
Keyword(s):  
Statistical Tests ◽  
Linear Regression Analysis ◽  
Coffea Canephora ◽  
Coffee Bean ◽  
Phytochemical Screening ◽  
Robusta Coffee ◽  
A Value ◽  
Coffee Beans ◽  
Ic50 Value ◽  
The Difference

Ground coffee is coffee beans that have been roasted, ground or ground so that they have a smooth shape. The purpose of this study was to determine the content of compounds in robusta coffee roasted seed extract (Coffea canephora) from plants produced by organic and inorganic fertilization, and to know the difference in compounds between the results of organic and inorganic fertilization. The characteristics of phytochemical screening were carried out qualitatively on alkaloids, flavonoids, tannins, terpenoids and saponins and the antioxidant activity was carried out by the DPPH (1,1-dipenyl-2-picrihidrazil) method. Phytochemical screening characteristic test results show that robusta coffee bean extract extract from the results of organic and inorganic fertilization both contain flavonoids, alkaloids, tannins, and saponins, while the antioxidant test activity of robusta coffee beans extracts shows differences based on the results of statistical tests of linear regression analysis with the IC50 value the highest antioxidant content was inorganic coffee roasted bean extract only 14.0629 ppm compared to the organic roasted extract with a value of 30.6159 ppmKeywords: Robusta Coffee (Coffea canophora), Phytochemical Screening, DPPH MethodABSTRAKKopi bubuk adalah biji kopi yang telah disangrai digiling atau ditumbuk sehingga mempunyai bentuk halus. Tujuan dari penelitian ini adalah untuk mengetahui kandungan senyawa dalam ekstrak biji sangrai kopi robusta (Coffe canephora) dari tanaman hasil pemupukan organik dan anorganik, dan mengetahui perbedaan senyawa antara hasil pemupukan organik dan anorganik. Karakteristik skrining fitokimia dilakukan secara kualitatif yang dilakukan terhadap alkaloid, flavonoid, tanin, terpenoid dan saponin dan aktivitas antioksidan dilakukan dengan metode DPPH (1,1-difenil-2-pikrihidrazil). Hasil uji karakteristik skrining fitokimia menunjukkan bahwa ekstrak biji sangrai kopi robusta dari hasil pemupukan oganik dan anorganik keduanya sama mengandung senyawa flavonoid, alkaloid, tanin, dan saponin,  sedangkan pada aktifitas uji antioksidan ekstrak biji sangrai kopi robusta menunjukan perbedaan berdasarkan hasil uji statistik analisis regresi linear dengan nilai IC50 kadar antioksidan paling tinggi adalah ekstrak biji sangrai kopi anorganik hanya 14,0629 ppm dibandingkan dengan ekstrak sangrai dari organik dengan nilai 30,6159 ppm.Kata kunci : Kopi Robusta (Coffea canophera), Skrining Fitokimia, Metode DPPH

scholarly journals Study of thermal behavior of phytic acid

2013 ◽  
Vol 49 (2) ◽  
pp. 275-283 ◽  
Author(s):  
André Luis Máximo Daneluti ◽  
Jivaldo do Rosário Matos
Keyword(s):  
Thermal Decomposition ◽  
Thermal Behavior ◽  
Mass Loss ◽  
Kinetic Study ◽  
Phytic Acid ◽  
Absorption Spectroscopy ◽  
Elemental Analysis ◽  
Reaction Order ◽  
Dehydration Process ◽  
Thermogravimetric Method

Phytic acid is a natural compound widely used as depigmenting agent in galenic cosmetic emulsions. However, we have observed experimentally that phytic acid, when heated to 150 ºC for around one hour, shows evidence of thermal decomposition. Few studies investigating this substance alone with regard to its stability are available in the literature. This fact prompted the present study to characterize this species and its thermal behavior using thermal analysis (TG/DTG and DSC) and to associate the results of these techniques with those obtained by elemental analysis (EA) and absorption spectroscopy in the infrared region. The TG/DTG and DSC curves allowed evaluation of the thermal behavior of the sample of phytic acid and enabled use of the non-isothermal thermogravimetric method to study the kinetics of the three main mass-loss events: dehydration I, dehydration II and thermal decomposition. The combination of infrared absorption spectroscopy and elemental analysis techniques allowed evaluation of the intermediate products of the thermal decomposition of phytic acid. The infrared spectra of samples taken during the heating process revealed a reduction in the intensity of the absorption band related to O-H stretching as a result of the dehydration process. Furthermore, elemental analysis results showed an increase in the carbon content and a decrease in the hydrogen content at temperatures of 95, 150, 263 and 380 °C. Visually, darkening of the material was observed at 150 °C, indicating that the thermal decomposition of the material started at this temperature. At a temperature of 380 °C, thermal decomposition progressed, leading to a decrease in carbon and hydrogen. The results of thermogravimetry coupled with those of elemental analysis allow us to conclude that there was agreement between the percentages of phytic acid found in aqueous solution. The kinetic study by the non-isothermal thermogravimetric method showed that the dehydration process occurred in two stages. Dehydration step I promoted a process of vaporization of water (reaction order of zero), whereas dehydration step II showed an order of reaction equal to five. This change in reaction order was attributed to loss of chemically bonded water molecules of phytic acid or to the presence of volatile substances. Finally, the thermal decomposition step revealed an order of reaction equal to one. It was not possible to perform the kinetic study for other stages of mass loss.

Genetic relationships among Brazilian strains of Aspergillus ochraceus based on RAPD and ITS sequences

2004 ◽  
Vol 50 (11) ◽  
pp. 985-988 ◽  
Author(s):  
Maria Helena Pelegrinelli Fungaro ◽  
Marciane Magnani ◽  
Laurival Antônio Vilas-Boas ◽  
Patrícia Cristina Vissotto ◽  
Márcia Cristina Furlaneto ◽  
...  
Keyword(s):  
Ochratoxin A ◽  
Sequence Data ◽  
Genetic Relationships ◽  
Its Region ◽  
Aspergillus Ochraceus ◽  
Coffee Bean ◽  
Coffee Beans ◽  
Major Species ◽  
Group A ◽  
Group B

Ochratoxin A (OA) is a mycotoxin that has been found in coffee beans and coffee beverages. Its toxicological profile includes carcinogenicity, nephrotoxicity, and immunotoxicity. Aspergillus ochraceus is the major species responsible for OA production in Brazilian coffee beans. The genetic relationships among 25 A. ochraceus strains collected from Brazilian coffee-bean samples were determined based on RAPD and internal transcribed spacer (ITS) sequence data. The isolates were resolved into 2 distinct groups, one with 4 strains (group A) and the other with 21 strains (group B). Specific nucleotide variations characterizing group A and B were found for both ITS1 and ITS2 regions. Group B is a new group proposed here to accommodate the majority of the Brazilian isolates. Each group was found to contain both toxigenic and nontoxigenic strains, indicating that there is no association between molecular genotypes and the ability to produce OA.Key words: Aspergillus ochraceus, ochratoxin A, ITS region (ITS1–5.8S–ITS2), RAPD.

scholarly journals Daya Hambat Ekstrak Biji Kopi Robusta (Coffea Canephora) terhadap Bakteri Porphyromonas gingivalis (in vitro)

2021 ◽  
Vol 18 (2) ◽  
pp. 69
Author(s):  
Rr. Nektara Titan Dianastri ◽  
Pudji Astuti ◽  
Rendra Chriestedy Prasetya
Keyword(s):  
Porphyromonas Gingivalis ◽  
Inhibition Zone ◽  
Coffea Canephora ◽  
Negative Control ◽  
Growth Media ◽  
Coffee Bean ◽  
Chlorogenic Acids ◽  
Robusta Coffee ◽  
Coffee Beans

Periodontitis is mostly caused by plaque and Pophyromonas gingivalis bacteria as the main cause. The outer membrane layer of the Porphyromonas gingivalis wall produces pathogenic virulence factors, such as lipopolysaccharides which will activate inflammatory cells and cause phagocytosis of antigens thereby triggering free radicals. Robusta coffee beans naturally contain caffeine, phenolic compounds, trigonellin, and chlorogenic acids as antibacterial and anti-inflammatory. The purpose of this study was to determine the inhibition of Robusta (Coffea canephora) coffee bean extract 0.5%; 0.75%; 1%; 1.25%; 1.5% and 3% on the growth of Porphyromonas gingivalis in vitro and to find out the lowest concentration of Robusta (Coffea canephora) coffee bean extract which has inhibitory effect on the growth of Porphyromonas gingivalis. In this study were divided into 8 treatment groups namely positive control, negative control, 0.5% robusta coffee bean extract, 0.75%, 1%, 1.25%, 1.5% and 3%. Petridish dishes containing TSA media that have been sterilized, added P. gingivalis suspension with density according to Mc standard. Farland Then a sterile white test blank with a diameter of 6 mm that is still sterile is placed on top of the bacterial growth media in accordance with the placement of the treatment group and dropped with all 8 treatment materials. After 24 hours incubated in a desiccator, the inhibition of robusta coffee bean extracts against the growth of Porphyromonas gingivalis bacteria was observed and data collection was done by measuring the inhibition zone using calipers. The results obtained robusta coffee bean extract at concentrations of 3%, 1.5%, 1.25% and 1%, have an antibacterial power which is suspected because Robusta coffee beans naturally contain ingredients such as caffeine, polyphenols and chlorogenic acids which have antibacterial activity while the robusta coffee bean extract with a concentration of 0.5% and 0.75% does not have antibacterial power against Pophyromonas gingivalis. Robusta coffee bean extract with a concentration of 1% is the smallest concentration of Robusta (Coffea canephora) coffee bean extract which can inhibit the growth of Porphyromonas gingivalis.

scholarly journals AlexNet convolutional neural network to classify the types of Indonesian coffee beans

2021 ◽  
Vol 905 (1) ◽  
pp. 012059
Author(s):  
Y Hendrawan ◽  
B Rohmatulloh ◽  
F I Ilmi ◽  
M R Fauzy ◽  
R Damayanti ◽  
...  
Keyword(s):  
Neural Network ◽  
Computer Vision ◽  
Sensitivity Analysis ◽  
Convolutional Neural Network ◽  
Confusion Matrix ◽  
Learning Rate ◽  
Agricultural Products ◽  
Coffee Bean ◽  
Coffee Beans ◽  
Non Destructive

Abstract Various types of Indonesian coffee are already popular internationally. Recently, there are still not many methods to classify the types of typical Indonesian coffee. Computer vision is a non-destructive method for classifying agricultural products. This study aimed to classify three types of Indonesian Arabica coffee beans, i.e., Gayo Aceh, Kintamani Bali, and Toraja Tongkonan, using computer vision. The classification method used was the AlexNet convolutional neural network with sensitivity analysis using several variations of the optimizer such as SGDm, Adam, and RMSProp and the learning rate of 0.00005 and 0.0001. Each type of coffee used 500 data for training and validation with the distribution of 70% training and 30% validation. The results showed that all AlexNet models achieved a perfect validation accuracy value of 100% in 1,040 iterations. This study also used 100 testing-set data on each type of coffee bean. In the testing confusion matrix, the accuracy reached 99.6%.

Composition of amino acids and fatty acids on Luwak coffee processing

Food Research ◽  
2021 ◽  
Vol 5 (3) ◽  
pp. 60-64
Author(s):  
Fitri ◽  
A. Laga ◽  
Z. Dwyana ◽  
A.B. Tawali
Keyword(s):  
Amino Acids ◽  
Fatty Acids ◽  
Fatty Acid ◽  
Amino Acid ◽  
Acid Content ◽  
Green Bean ◽  
Total Amino Acid ◽  
Coffee Bean ◽  
Roasted Coffee ◽  
Coffee Beans

The processing carried out on coffee beans such as fermentation and roasting can affect the contents of amino and fatty acids of coffee beans. This study aimed to determine the amount of amino acid and fatty acid content in Luwak coffee bean during processing. The amino acids of coffee were analyzed using HPLC, while fatty acids of coffee were analyzed using GC-MS. The results showed a change in total amino acid content in raw coffee bean (3.04%), green bean coffee (6.93%), and roasted coffee (6.83%). The total fatty acid of raw coffee bean (1199.86 mg/100 g), green bean coffee (3147.56 mg/100 g), and roasted coffee (6282.4 mg/100 g) also experienced significant changes

Werkstoffaufbau und diffusiver Stofftransport aufgezeigt an ausgewählten Beispielen / Material structure and diffusive mass transport as pointed out by means of selected examples

2000 ◽  
Vol 6 (4) ◽  
pp. 429-450
Author(s):  
R. Kriegel ◽  
A. Buchwald ◽  
Ch. Kaps
Keyword(s):  
Mass Transport ◽  
Diffusion Coefficients ◽  
Transport Mechanism ◽  
Diffusion Models ◽  
Second Law ◽  
Material Structure ◽  
Ion Diffusion ◽  
Oxygen Ion ◽  
Oxygen Ion Diffusion

Abstract The diffusive mass transport in materials is above all determined by the material structure. The experimental determination of diffusion coefficients is based on diffusion models, which results from special mathematical solutions of Fick's second law and its corresponding boundary conditions. The general usefulness of these diffusion models will be described using some examples, e. g. the diffusion of deteriorating salts in masonry materials, the oxygen ion diffusion in mixed conducting ceramics and the cation exchange in single crystals. The measurement of the diffusion coefficients results in a better comprehension of the transport mechanism as well as of the "morphology" of the transport medium, which allows to optimize the conditions of the mass transport and the material structure and composition, respectively.

scholarly journals Modeling Drying of Degenerated Calluna vulgaris for Wildfire and Prescribed Burning Risk Assessment

Forests ◽  
2020 ◽  
Vol 11 (7) ◽  
pp. 759 ◽  
Author(s):  
Torgrim Log
Keyword(s):  
Mathematical Model ◽  
Numerical Model ◽  
Mass Loss ◽  
Diffusion Coefficients ◽  
Prescribed Burning ◽  
Fire Hazard ◽  
Fire Risk ◽  
Calluna Vulgaris ◽  
Fire Danger ◽  
Drying Process

Research highlights: Moisture diffusion coefficients for stems and branches of degenerated Calluna vulgaris L. have been obtained and a mathematical model for the drying process has been developed and validated as an input to future fire danger modeling. Background and objectives: In Norway, several recent wildland–urban interface (WUI) fires have been attributed to climate changes and accumulation of elevated live and dead biomass in degenerated Calluna stands due to changes in agricultural activities, i.e., in particular abandonment of prescribed burning for sheep grazing. Prescribed burning is now being reintroduced in these currently fire prone landscapes. While available wildfire danger rating models fail to predict the rapidly changing fire hazard in such heathlands, there is an increasing need for an adapted fire danger model. The present study aims at determining water diffusion coefficients and develops a numerical model for the drying process, paving the road for future fire danger forecasts and prediction of safe and efficient conditions for prescribed burning. Materials and methods: Test specimens (3–6 mm diameter) of dead Calluna stems and branches were rain wetted 48 h and subsequently placed in a climate chamber at 20 °C and 50% relative humidity for mass loss recordings during natural convection drying. Based on the diameter and recorded mass versus time, diffusion coefficients were obtained. A numerical model was developed and verified against recoded mass loss. Results: Diffusion coefficients were obtained in the range 1.66–10.4 × 10−11 m2/s. This is quite low and may be explained by the very hard Calluna “wood”. The large span may be explained by different growth conditions, insect attacks and a varying number of years of exposure to the elements after dying. The mathematical model described the drying process well for the specimens with known diffusion coefficient. Conclusions: The established range of diffusion coefficients and the developed model may likely be extended for forecasting moisture content of degenerated Calluna as a proxy for fire danger and/or conditions for efficient and safe prescribed burning. This may help mitigate the emerging fire risk associated with degenerated Calluna stands in a changing climate.

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