Engenharia Agrícola
URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/10363
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Item Impact of Slow Drying in a Cold Room on Coffee Sensory, Chemical, and Physical Properties(Associação Brasileira de Engenharia Agrícola, 2024-04-26) Jordan, Rodrigo A.; Oliveira, Fabrício C. de; Argandoña, Eliana J. S.; Motomiya, Anamari V. A.; Santos, Rodrigo C.This study aimed to evaluate the duplicity and synergism of slow drying and storage processes at low temperatures, using a refrigerated room under suitable conditions for coffee fruit just after harvest. A cold room was prepared to receive and store coffee fruit in bulk directly from the field, perform slow drying, and maintain water content at approximately 12% during three months of storage. The room operated at temperatures between 7 and 14 ºC and relative humidity between 37 and 41%. The coffee variety used was the Conilon Yellow 62. The initial water content reduction period from 54% (wb) to 12% (wb) was two months. For comparison, coffee harvested from the same batch was dried on a covered suspended bed. Results showed that the coffee dried and stored in the cold room received a sensory score of 86.41, while that dried on a suspended bed obtained a sensory score of 84.16. Moreover, the coffee dried and stored in the cold room had a higher energy content. Colorimetric analysis showed that the dried grains stored in the cold room had a reduction in the "a" coordinate, indicating an approximation to the green color. The cold room also allowed for extended storage of the coffee grains.Item ATR-FTIR for characterizing and differentiating dried and ground coffee cherry pulp of different varieties (Coffea arabica L.)(Associação Brasileira de Engenharia Agrícola, 2021) Barrios-Rodríguez, Yeison; Collazos-Escobar, Gentil A.; Gutiérrez-Guzmán, NelsonThis study aimed to evaluate the performance of the infrared spectrum in the range of 4000−650 cm−1 for characterizing and differentiating dried and ground coffee cherry pulp of different varieties. The spectral data were subjected to first and second derivative treatments to perform the statistical analyses. Three varieties of coffee pulp were previously characterized for color, water activity, moisture, chlorogenic acids, and caffeine. The results of principal component analysis (PCA) showed that Fourier transform infrared (FTIR) spectroscopy is a viable technique for characterizing and differentiating dried and ground coffee cherry pulp among different varieties, showing the best differentiation with treatment of data from the first derivative, which was mainly associated with the caffeine content and chlorogenic acids. This study is the first investigation of FTIR spectroscopy with attenuated total reflectance for characterizing dried and ground coffee cherry pulp from coffee varieties grown in Colombia.Item Influence of different temperatures and airflows on drying of natural and pulped coffee(Associação Brasileira de Engenharia Agrícola, 2020) Alves, Guilherme E.; Borém, Flávio M.; Andrade, Ednilton T.; Isquierdo, Éder P.; Siqueira, Valdiney C.; Dias, Camila de A.This study aimed to evaluate drying kinetics for natural and pulped coffee, using diferente temperatures and drying airflows. For the conduction of the experiment, coffee fruits (Coffea arabica L. cv. Topázio) were harvested manually, selecting only ripe fruits and subsequent to the hydraulic separation. For drying the coffee, use a mechanical dryer with two temperatures (40 and 45°C) and four drying air streams (24; 60; 96 and 132 m3.min- 1.m-2). Twelve models for employees to describe the drying kinetics of coffees. Among the models used to describe the drying process of natural coffee and pulped coffee, according to the results of the coefficient of determination, relative mean error, standard deviation of estimates and distribution of waste distribution, proposed model for the Only one that presents fit for all as conditions study. The temperature of 45 ° C and the airflows of 96 and 132 m3.min-1.m-2 provide the shortest drying times regardless of the coffee processing type.Item Mathematical modelling and immediate and latent quality of natural immature coffee under different drying conditions(Associação Brasileira de Engenharia Agrícola, 2019) Andrade, Ednilton T. de; Lemos, Isabella A.; Dias, Camila de A.; Rios, Paula de A.; Borém, Flávio M.This work aimed to study the immediate and latent effects of different relative humidities on the quality of dried coffee fruits, describe the drying kinetics of natural immature coffee (Coffea arabica L.), and evaluate the mathematical model that best fits the experimental drying data. The drying was carried out in a fixed layer dryer coupled to a composite air conditioning system in which the drying air was controlled with an air flow of 20 m3.min1.m-2, at a temperature of 40 °C, and at relative humidities of 10%, 17.5% and 32.5%. Manually harvested coffee fruits were used and dried to a mean water content of 0.120 dry basis (d.b). After drying, the kinetic curve and the physical and physiological properties were determined. The coffee was stored in permeable packs for 6 months. The electrical conductivity, potassium leaching, and colour analysis were performed every 2 months. For the modelling adjustment, the models were tested, and the Midilli model had the best fit with the drying kinetics of the immature coffee. No immediate damage was observed in the physical and physiological quality of the coffees, and latent damage was perceived after 120 days of storage for the natural immature coffees.Item Use of data mining and spectral profiles to differentiate condition after harvest of coffee plants(Associação Brasileira de Engenharia Agrícola, 2012-01) Lamparelli, Rubens A. C.; Johann, Jerry A.; Santos, Éder R. dos; Esquerdo, Julio C. D. M.; Rocha, Jansle V.This study aimed at identifying different conditions of coffee plants after harvesting period, using data mining and spectral behavior profiles from Hyperion/EO1 sensor. The Hyperion image, with spatial resolution of 30 m, was acquired in August 28 th , 2008, at the end of the coffee harvest season in the studied area. For pre-processing imaging, atmospheric and signal/noise effect corrections were carried out using Flaash and MNF (Minimum Noise Fraction Transform) algorithms, respectively. Spectral behavior profiles (38) of different coffee varieties were generated from 150 Hyperion bands. The spectral behavior profiles were analyzed by Expectation- Maximization (EM) algorithm considering 2; 3; 4 and 5 clusters. T-test with 5% of significance was used to verify the similarity among the wavelength cluster means. The results demonstrated that it is possible to separate five different clusters, which were comprised by different coffee crop conditions making possible to improve future intervention actions.Item Variabilidade espacial da força de desprendimento de frutos do cafeeiro(Associação Brasileira de Engenharia Agrícola, 2014-11) Ferraz, Gabriel A. e S.; Silva, Fábio M. da; Oliveira, Marcelo S. de; Silva, Flavio C. da; Bueno, Rafael de L.O objetivo deste trabalho foi utilizar técnicas de georreferenciamento e de geoestatística para analisar a variabilidade espacial da força de desprendimento de frutos de cafeeiros por meio de semivariogramas e pela interpolação por krigagem. O trabalho foi conduzido no município de Três Pontas - MG, Brasil. A força de desprendimento dos frutos verdes e de cerejas dos cafeeiros foi obtida por meio de um protótipo de dinamômetro em pontos georreferenciados. A dependência espacial dos dados foi analisada por meio de ajustes de semivariogramas, clássico e robusto, para o método dos mínimos quadrados ordinários e ponderados, e apenas o ajuste clássico, para os métodos da máxima verossimilhança e máxima verossimilhança restrita. Testaram-se, para cada um dos métodos, os modelos esférico, exponencial e gaussiano. Os mapas de isolinhas obtidos por krigagem foram produzidos, baseados no melhor método e modelo de ajuste da função semivariograma, que foram obtidos pelas estatísticas de validação. As variáveis em estudo apresentaram estruturas de dependência espacial, as quais foram modeladas pelos semivariogramas, o que possibilitou a confecção dos mapas de isolinhas de distribuição espacial, obtidos por krigagem. Foi possível identificar os locais mais propícios para se iniciar a colheita seletiva e mecanizada dos frutos do cafeeiro.Item Kinetics of mass loss of arabica coffee during roasting process(Associação Brasileira de Engenharia Agrícola, 2016-03) Vargas-Elías, Guillermo A.; Corrêa, Paulo C.; Souza, Natália R. de; Baptestini, Fernanda M.; Melo, Evandro de C.Roasting is one of the most complex coffee processing steps due to simultaneous transfers of heat and mass. During this process, beans lose mass because of fast physical and chemical changes that will set color and flavor of the commercial coffee beverage. Therefore, we aimed at assessing the kinetics of mass loss in commercially roasted coffee beans according to heating throughout the processing. For that, we used samples of 350-g Arabica coffee processed grains with water content of 0.1217 kg a kg-1 , in addition to a continuous roaster with firing gas. The roaster had initial temperatures of 285, 325, 345 and 380 °C, decreasing during the process up to 255, 285, 305 and 335 °C respectively. Mass loss was calculated by the difference between grain weight before and after roasting. We observed a linear variation directly dependent on roaster temperature. For each temperature during the process was obtained a constant mass loss rate, which was reported by the Arrhenius model with r 2 above 0.98. In a roaster in non-isothermal conditions, the required activation energy to start the mass loss in a commercial coffee roasting index was 52.27 kJ mol-1 .