17H-25 |
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E. HERMAN-LARA1, C. E. Martínez-Sánchez1, M. A. García-Alvarado2, A. Villalobos1, R. Cobos1, and I. R. Huerta1. (1) Biochemical Engineering Dept., Instituto Tecnologico de Tuxtepec, Calz. Dr Victor Bravo Ahuja s/n, Col. 5 de Mayo, Tuxtepec, Oax., 68360, Mexico, (2) Chemical and Biochemical Dept., Instituto Tecnologico de Veracruz, Miguel A. de Quevedo No.2779, Col. Formando Hogar, Veracruz, Ver., 91897, Mexico Green vanilla beans lack typical flavor and color of vanilla. To obtain these sensory properties is necessary a maturity process of several steps. Drying process is mainly one of these operations; where vanilla obtains its main characteristics of quality like moisture and vanillin contents. Due drying is processed in a handle form and the physical conditions of green vanilla are different each year; then cured vanilla quality is not always the same. Therefore, the objective of this work was to simulate the drying curves of green vanilla beans to different conditions of operation for understanding the behavior of this product through of the drying process. A mathematical model of four non-linear partial differential equations in conjunction with three non-linear algebraic equations represented the global and interface balances of matter and energy of the product and the air. The equation system was solved employing the Runge Kutta and Difference Finites methods assuming the pseudo-steady state for the air variables. This mathematical model considered the dominant phenomenon (internal or external) during the drying. Experimental curves were obtained to 70 and 80 Celsius degree with different air speeds: 2.45 y 3.10 m/s and thickness of particles: 0.1 and 1.0 cm. Simulation predicted with good agreement the experimental behaviour of the drying curves to different conditions. The predicted curves fitted experimental results in thin thickness too, where the mass transfer is external and therefore the interface conditions can be considered variable with respect to time and space. The importance of fixed bed could be considered in further studies. Simulation could help to Indians producers of vanilla to standardize the quality of this product during the curing specially in the drying operation. Moreover, the simulation could save time and energy at the cured of vanilla beans.
Session 17H, Food Engineering: Thermal processes
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