A generic drying model for cassava products

Abstract

Drying is a a critical step in many food processes, e.g. in the production of cassava flour. No specific Computer Aided Engineering (CAE) tool is available to assist in the design of cassava drying equipment. In this study, a convective-diffusive model was selected in the literature for its genericity and suitability for engineering purposes. Three drying kinetics were sufficient to identify the required temperature-dependent effective diffusivity. They were measured under 40–${80}^{°}C$ air, flowing perpendicular to the cassava cylinders. For validation, a total of 36 kinetics were measured on four cassava products of different origins, levels of transformation, geometries, dried in air flows at 40–${80}^{°}C,$ parallel or perpendicular to the product layer. Using 3 properties taken from the literature and few straightforward lab measurements, the model was able to accurately predict (RMSE: 0.04 d.b.) all drying kinetics for cassava products from flour to root cuts.

KEYWORDS:

• Drying
• simulation
• diffusivity
• cassava

Acknowledgments

The authors thank Dr. Jean-Michel Méot for his advice and his expertise. The author also thank Jean-Paul Fleuriot for his technical support. They also extend their thanks to Pr. Noël Akissoé’s research team at the Faculty of Agronomic Sciences (FSA), Bénin; Alexandre Bouniol; and the cassava processors from Kétou, Bénin, to help them to acquire the fermented roots. The authors also gratefully acknowledge Dr. Dominique Dufour for facilitating this work as RTB project coordinator.

Correction Statement

This article has been corrected with minor changes. These changes do not impact the academic content of the article.

Disclosure statement

The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.

Notes

1 The fan motor had a power of $4 kW$ and was controlled by a $20-50 Hz$ frequency inverter. The steam generator had a capacity of $10 kg·h^{-1},$ 0 to $100 \%$ adjustable. The electrical resistances had a power of $12 kW,$ and were controlled by a dimmer switch with $0-100 \%$ modulation.

2 https://imagej.net/

Additional information

Funding

The research conducted in preparation for this study was undertaken as part of, and funded by, the CGIAR Research Program on Roots, Tubers and Bananas (RTB) and supported by CGIAR Trust Fund contributors (https://www.cgiar.org/funders/) and French Agricultural Research Center for International Development (CIRAD), Montpellier, France.