Modelling of unsteady spatially distributed drying parameters assessed non-destructively in a small industrial food dryer

Modelling of unsteady spatially distributed drying parameters assessed non-destructively in a small industrial food dryer

Waseem Amjada*, Anjum Munira, Liaqat Ali Shahidb, Barbara Sturmc

aDepartment of Energy Systems Engineering, University of Agriculture Faisalabad, Pakistan; bPakistan Agricultural Research Council (PARC) Islamabad, Pakistan; cDepartment of Agricultural & Biosystems Engineering, University of Kassel, Germany

Modelling of unsteady moisture diffusion in relation of product temperature become complex due to complexity involve in solving complex numerical equations. In this study, a simplified methodology (determination of drying parameters: lag factor and drying constant) used to model change in food quality with its temperature in an industrial dryer using potato slices (6mm thick, 60°C). A shiftable real time data acquisition box was developed. Linear and exponential models were developed to estimate product quality as a function of dimensionless moisture ratio, linked with change in product temperature. The experimental and models predicted color kinetics using variable values of lag factor and drying constant revealed good correlation coefficients (R2 = 0.88-0.99, P ˂ 0.0001). The change in spatially distributed quality parameter with product weight loss was successfully assessed and modelled unsteadily, providing a better way to optimize the design process as a function of food physiognomies in an industrial dryer.

Keywords: Unsteady modelling, Real time data acquisition, image analysis

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How to cite this article:
Waseem Amjad, Anjum Munir, Liaqat Ali Shahid, Barbara Sturm.Modelling of unsteady spatially distributed drying parameters assessed non-destructively in a small industrial food dryer. American Journal of Agricultural Research, 2020,5:74.


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