Engenharia Agrícola

URI permanente para esta coleçãohttps://thoth.dti.ufv.br/handle/123456789/10363

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Resultados da Pesquisa

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    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.
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    Sorption isotherms and isosteric heat of pericarp and endosperm tissues of arabica coffee fruit
    (Associação Brasileira de Engenharia Agrícola, 2020) Dias, Camila de A.; Andrade, Ednilton T. de; Lemos, Isabella A.; Borém, Flávio M.; Barros, Ezequiel A.
    The aim of this study was to evaluate and model the hygroscopic equilibrium and isosteric heat curves of pericarp and endosperm tissues of arabica (Coffea arabica) coffee fruit, in different temperature and relative humidity conditions. Sorption isotherms were drawn under temperatures from 20°C to 70°C and relative humidity ranging between 10% and 90% until the product reached the equilibrium water content with the environment. The experiment was set up in a 4 × 4 factorial scheme (four relative humidity of the drying air and three tissues of the coffee cherry pericarp + endosperm [1: exocarp + part of the mesocarp, 2: mesocarp, 3: endocarp, 4: endosperm]), in a completely randomized design, with three repetitions. The results were examined by analysis of variance and regression using the STATISTICA 5.0 statistical software. Among the analyzed models, the ones that best fit the experimental data were modified GAB, for exocarp + part of mesocarp and mesocarp, modified Henderson, for endocarp, and Sabbab for endosperm. It was observed that, for all treatments, the lower water contents required a higher amount of energy to reach the equilibrium water content, and the integral isosteric heat decreased with the increasing equilibrium water content.