NOVEL MATHEMATICAL MODEL WITH INTEGRATIVE OPTIMIZATION FOR MICROWAVE DRYING OF  OLIVE LEAVES (OLEA EUROPAEA) TO ENHANCE BIOACTIVE COMPOUNDS PRESERVATION, ANTIOXIDANT ACTIVITY, AND ENERGY EFFICIENCY

Taous KADDOUR; Nassima CHAHER-BAZIZI; Farid CHEBROUK; Naima SAIDENE; Lamia HANIFI; Lydia KAROU; Mostapha BACHIR-BEY

doi:10.24193/subbchem.2026.1.06

Authors

Taous KADDOUR Université de Bejaia, Faculté des Sciences de la Nature et de la Vie, Laboratoire de Biochimie Appliquée, 06000 Bejaia, Algeria. *Corresponding author: taous.kaddour@univ-bejaia.dz https://orcid.org/0009-0000-8619-9265
Nassima CHAHER-BAZIZI Université de Bejaia, Faculté des Sciences de la Nature et de la Vie, Laboratoire de Biochimie Appliquée, 06000 Bejaia, Algeria https://orcid.org/0000-0002-9317-4151
Farid CHEBROUK Centre de Recherche Scientifique et Technique en Analyses Physico-Chimiques (CRAPC), BP384, Bou-Ismail, Tipaza 42004, Algeria; Plateau Technique d'Analyses Physico-Chimiques, Route de Targa Ouzemmour 06000, Université de Bejaia, Algeria https://orcid.org/0000-0003-2257-9028
Naima SAIDENE Université de Bejaia, Faculté des Sciences de la Nature et de la Vie, Laboratoire de Biochimie Appliquée, 06000 Bejaia, Algeria https://orcid.org/0000-0002-7075-0726
Lamia HANIFI Université de Bejaia, Faculté des Sciences de la Nature et de la Vie, Laboratoire de Biochimie Appliquée, 06000 Bejaia, Algeria https://orcid.org/0009-0003-2610-6233
Lydia KAROU Université de Bejaia, Faculté des Sciences de la Nature et de la Vie, Laboratoire de Biochimie Appliquée, 06000 Bejaia, Algeria
Mostapha BACHIR-BEY Université de Bejaia, Faculté des Sciences de la Nature et de la Vie, Laboratoire de Biochimie Appliquée, 06000 Bejaia, Algeria https://orcid.org/0000-0002-9987-1505

DOI:

https://doi.org/10.24193/subbchem.2026.1.06

Keywords:

Microwave drying, olive leaves, bioactive compounds, antioxidant activity, mathematical modeling, energy efficiency

Abstract

This study optimized the microwave drying of olive leaves by integrating mathematical modeling and proposing a novel drying model, along with a comprehensive analysis of energy efficiency and bioactive compound preservation. Experiments were conducted at microwave power levels ranging from 100 to 1000 W, assessing drying kinetics, energy efficiency, and retention of bioactive compounds. The optimal power of 700 W achieved a drying time of 21 minutes while preserving key bioactive compounds, with TPC, TFC, and antioxidant activity reaching 108.79 mg GAE/g DM, 12.12 mg RE/g DM, and 23.25 mg GAE/g DM, respectively. Several mathematical models from the literature were evaluated, and the Logarithmic, Modified Henderson–Pabis II, and Hii et al. models showed excellent agreement with the experimental data (R² > 0.99). The proposed new model also demonstrated strong predictive accuracy, with high R² values and low root mean square error and reduced chi-square (χ²). The lowest specific energy consumption was 0.236 × 10⁵ MJ/kg H₂O, accompanied by the highest energy efficiency. These results demonstrate that intermediate microwave power provides an optimal balance between energy efficiency, processing time, and bioactive compound preservation, highlighting both practical and economic advantages for olive leaf drying.

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