High-temperature Thin-layer Drying Kinetic of Cultivated and Wild Algerian Olive Leaves

Modeling and Effect on Oleuropein and Chlorophyll Contents

Authors

  • Aissa Boukhiar
    Affiliation
    Research Laboratory in Food Technology, Faculty of Technology, University of Boumerdes, Frantz Fanon city, Boumerdes 35000, Algeria
    Department of Process Engineering, Faculty of Technology, University of Boumerdes, Frantz Fanon city, Boumerdes 35000, Algeria
  • Salem Benamara
    Affiliation
    Department of Process Engineering, Faculty of Technology, University of Boumerdes, Frantz Fanon city, Boumerdes 35000, Algeria
  • Yougourthane Bouchal
    Affiliation
    Department of Food Phytochemistry, Instituto de la Grasa (Spanish National Research Council, CSIC), Ctra. de Utrera km. 1, Pablo de Olavide University Campus, Building 46, 41013 Seville, Spain
  • Kahina Touderte
    Affiliation
    Department of Process Engineering, Faculty of Technology, University of Boumerdes, Frantz Fanon city, Boumerdes 35000, Algeria
  • Siham Messouidi
    Affiliation
    Department of Process Engineering, Faculty of Technology, University of Boumerdes, Frantz Fanon city, Boumerdes 35000, Algeria
https://doi.org/10.3311/PPch.20264

Abstract

Olive leaves (OLs) are well known for being rich in oleuropein, their main bioactive molecule which has recently been attracting great interest from the scientific community due to its antiviral properties, including Covid-19 disease. Furthermore, the high-temperature/short-time drying process has found applications for various plants and food processing, which might be also implemented for the drying of OLs. This study focuses on: 1. the mathematical modeling of thin-layer high-temperature-drying (HTD) kinetic of olive (var. Chemlal and Oleaster) leaves, and 2. the determination of HTD effect on some physicochemical properties (oleuropein, chlorophylls, and CIELab color parameters) of the dried olive leaves (DOLs). For this, four drying temperatures (100, 120, 140, and 160 °C) were applied. For comparison purposes, low-temperature DOL samples were also prepared. The obtained data have shown that among the tens tested mathematical models, the Midilli et al. model describes more correctly experimental data for all drying temperatures and for both olive leaf varieties (R2 = 0.9960, SEE = 0.0085, RMSE = 0.0165 and χ2 = 0.0006). Moreover, the results show that the HTD at 120 and 160 °C does not differ from freeze-drying in terms of oleuropein retention (p < 0.05), highlighting the technological interest in the high-temperature/short-time drying process. Considering the biological value of oleuropein, in particular its antiviral activity, the study deserves further investigation in order to elucidate certain questions such as the storability of DOLs, and their valorization as fortification ingredient in food and pharmaceutical formulations, evaluation in vitro of their biological activities, etc.

Keywords:

high-temperature-drying, dried olive leaves, mathematical modeling, oleuropein, chlorophylls

Citation data from Crossref and Scopus

Published Online

2022-10-03

How to Cite

Boukhiar, A., Benamara, S., Bouchal, Y., Touderte , K., Messouidi , S. “High-temperature Thin-layer Drying Kinetic of Cultivated and Wild Algerian Olive Leaves: Modeling and Effect on Oleuropein and Chlorophyll Contents”, Periodica Polytechnica Chemical Engineering, 66(4), pp. 660–674, 2022. https://doi.org/10.3311/PPch.20264

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