DETERMINATION OF THERMAL PROPERTIES OF COFFEE BEANS AT DIFFERENT DEGREES OF ROASTING

Authors

  • Danilo Barbosa Cardoso Universidade Federal de Lavras
  • Ednilton Tavares de Andrade Universidade Federal de Lavras
  • Renso Alfredo Aragón Calderón Universidade Federal de Lavras
  • Mariane Helena Sanches Rabelo Universidade Federal de Lavras
  • Camila de Almeida Dias Universidade Federal de Lavras
  • Isabela Ávila Lemos Universidade Federal de Lavras

Keywords:

specific heat, thermal conductivity, thermal diffusivity

Abstract

The aim of this study was to determine the main thermal properties of the granular mass of coffee (specific heat, thermal conductivity, and thermal diffusivity) for different degrees of roasting, as well as to model and simulate thermal conductivity at different degrees of roasting. For determination of specific heat, the mixing method was used, and for thermal conductivity, the theoretically infinite cylinder method with a central heating source. Thermal diffusivity was simulated algebraically using the results of the properties cited above and of the apparent specific mass of the product. Thermal conductivity was also simulated and optimized through finite element analysis software. At darker roasting, there was an increase in specific heat and a reduction in thermal conductivity and thermal diffusivity. Comparing thermal conductivity determined in relation to simulated and optimized conductivity, the mean relative error was 1.02%, on average.

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Published

2018-12-19

How to Cite

CARDOSO, D. B.; ANDRADE, E. T. de; CALDERÓN, R. A. A.; RABELO, M. H. S.; DIAS, C. de A.; LEMOS, I. Ávila. DETERMINATION OF THERMAL PROPERTIES OF COFFEE BEANS AT DIFFERENT DEGREES OF ROASTING. Coffee Science - ISSN 1984-3909, [S. l.], v. 13, n. 4, p. 498–509, 2018. Disponível em: https://coffeescience.ufla.br/index.php/Coffeescience/article/view/1491. Acesso em: 19 jun. 2024.

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