Abstract
This study investigated the effects of microwave pretreatment on drying behavior, moisture transport, and thermodynamic properties of untreated Barhi dates (UBD) and microwave-pretreated Barhi dates (MBD) under different drying temperatures and air velocities. In addition, thin-layer drying models were evaluated to identify the most suitable predictive model. The results demonstrated that microwave pretreatment significantly enhanced drying efficiency, reducing drying time by up to 21% and accelerating internal moisture transfer, particularly during the initial drying stage. Among the evaluated models, the Logarithmic model provided the most accurate prediction of moisture ratio. Microwave pretreatment improved parameter consistency and slightly enhanced model accuracy, indicating more uniform moisture redistribution within the fruit. Both effective moisture diffusivity (Deff) and the convective mass transfer coefficient (hm) increased with temperature and air velocity, with MBD exhibiting up to approximately 367% higher Deff and 359% higher hm than UBD. Biot numbers increased with temperature (≈ 20–23% per 10 °C) but decreased with increasing air velocity, whereas Dincer numbers declined sharply (≈ 36–42% per 10 °C). Thermodynamic analysis confirmed that the drying process was endothermic and non-spontaneous. Compared with UBD, MBD exhibited slightly higher activation energy and enthalpy but lower Gibbs free energy, reflecting enhanced moisture mobility and improved energy efficiency. Overall, microwave pretreatment improved drying kinetics, moisture uniformity, and model predictability, providing a robust framework for optimizing thin-layer drying of Barhi dates at the industrial scale.
Data availability
The data supporting the findings of this study are available from the corresponding author upon request.
References
Abdelkarim, D. O. et al. Extending the shelf life of fresh Khalal Barhi dates via an optimized postharvest ultrasonic treatment. Plants 11, 2029 (2022).
Fikry, M., Yusof, Y. A., Alqahtani, N. & Al-Awaadh, A. in Sustainable Valorization of Date Palm By-products and Wastes 139–158 (Elsevier, 2026).
Al-Mssallem, M. Q., Alqurashi, R. M. & Al-Khayri, J. M. In Bioactive Compounds in Underutilized Fruits and Nuts 1–15 (Springer, 2019).
Fikry, M., Al-Awaadah, A. & Rahman, R. Production and characterization of palm date powder rich in dietary fiber. J. Food Meas. Charact. 15, 2285–2296 (2021).
Shareef, S. H. Study the active compounds of Barhi date seed extracts. Euphrates J. Agricultural Sci. 17, 1074–1085 (2025).
Alqahtani, N. K., Ali, S. A. & Alnemr, T. M. Quality preservation of date palm (Phoenix dactylifera L.) fruits at the Khalal stage: a review on current challenges, preservation methods, and future trends. Front. Sustainable Food Syst. 9, 1558985 (2025).
Fikry, M. et al. Mathematical modeling of sorption isotherms and the thermodynamic properties of vacuum-dried and freeze-dried Barhi dates. Sci. Rep. 15, 19781 (2025).
Cheraghi, S. & Hamdami, N. A study of kinetics and some resulting physical characteristics of dates (Barhi variety) during drying (modeling and experimental validation). Iran. J. Biosyst. Eng. 41 (2010).
Sagarika, N. Development of Drying Technology for Date Palm Fruits Using Novel Techniques (Anand agricultural university, 2020).
Fikry, M. et al. Ultrasound-assisted extraction of bioactive compounds from Longan seeds powder: kinetic modelling and process optimization. Ultrason. Sonochem. 108, 106949 (2024).
Manzoor, S., Yusof, Y. A., Tawakkal, I. S. M. A. & Fikry, M. Thin-layer drying characteristics of Papaya (Carica papaya) Peel using convection oven and microwave drying. Pertanika J. Sci. Technol. 27 (2019).
Kahraman, O., Malvandi, A., Vargas, L. & Feng, H. Drying characteristics and quality attributes of Apple slices dried by a non-thermal ultrasonic contact drying method. Ultrason. Sonochem. 73, 105510 (2021).
Fikry, M. et al. Kinetic modelling of moisture transfer and phytochemical properties in Longan seeds: impact of ultrasonic pretreatment and microwave drying process. Food Bioprocess. Technol. 1–18 (2024).
Apinyavisit, K., Nathakaranakule, A., Mittal, G. S. & Soponronnarit, S. Heat and mass transfer properties of Longan shrinking from a spherical to an irregular shape during drying. Biosyst. Eng. 169, 11–21 (2018).
Nadi, F. & Tzempelikos, D. Vacuum drying of apples (cv. Golden Delicious): drying characteristics, thermodynamic properties, and mass transfer parameters. Heat Mass Transf. 54, 1853–1866 (2018).
Al-Awaadh, A. M., Hassan, B. H. & Ahmed, K. Hot air drying characteristics of Sukkari date (Phoenix dactylifera L.) and effects of drying condition on fruit color and texture. Int. J. Food Eng. 11, 421–434 (2015).
Muhammad, A. I., Al-Dairi, M., Al‐Khalili, M., Al‐Habsi, N. & Pathare, P. B. Drying Kinetics, Characteristics, and quality assessment of Hot‐Air dried Semi‐Dried Biser stage dates using computer vision. Heat. Transf. 54, 4223–4238 (2025).
Alvi, T., Khan, M. K. I., Maan, A. A., Shahid, M. & Sablani, S. Microwaves as sustainable approach for artificial ripening of date fruit cv. Khupra to reduce fruit waste. Food Bioscience. 54, 102829 (2023).
Fikry, M. et al. Modeling mass transfer kinetics and thermodynamic properties of ultrasonically pretreated and untreated Apple slices during Air-Frying. J. Food Process Eng. 47, e14745 (2024).
Rodrigues, M. C. K. et al. Potential use of green banana Peel waste: modeling of drying and determination of physicochemical and antioxidant properties. Biomass Convers. Biorefinery. 14, 14095–14106 (2024).
Mondal, I. H. & Dash, K. K. Textural, color kinetics, and heat and mass transfer modeling during deep fat frying of Chhena Jhili. J. Food Process. Preserv. 41, e12828 (2017).
Dehghannya, J., Gorbani, R. & Ghanbarzadeh, B. Effect of ultrasound-assisted osmotic dehydration pretreatment on drying kinetics and effective moisture diffusivity of Mirabelle Plum. J. Food Process. Preserv. 39, 2710–2717 (2015).
Dincer, I. & Hussain, M. Development of a new Bi–Di correlation for solids drying. Int. J. Heat Mass Transf. 45, 3065–3069 (2002).
Fikry, M. et al. Influence of ultrasonic pretreatment on drying and thermodynamic characteristics of Asian Seabass fish skin during air-frying process. J. Food Meas. Charact. 18, 4147–4160 (2024).
Akhoundzadeh Yamchi, A., Sharifian, F., Khalife, E. & Kaveh, M. Drying kinetic, thermodynamic and quality analyses of infrared drying of truffle slices. J. Food Sci. 89, 3666–3686 (2024).
Fikry, M. & Al-Awaadh, A. M. Characteristics of dynamics sorption isotherms of date flesh powder rich in fiber. Int. J. Food Eng. 12, 469–480 (2016).
Lomauro, C., Bakshi, A. & Labuza, T. Evaluation of food moisture sorption isotherm equations. Part I: Fruit, vegetable and meat products. Lebensmittel-Wissenschaft Und Technologie. 18, 111–117 (1985).
Hii, C. L., Menon, A. S., Chiang, C. L. & Sharif, S. Kinetics of hot air roasting of cocoa Nibs and product quality. J. Food Process. Eng. 40 (2017).
Crank, J. The Mathematics of Diffusion: 2d Ed (Clarendon, 1975).
Özkan-Karabacak, A., Acoğlu, B., Yolci Ömeroğlu, P. & Çopur, Ö. U. Microwave pre‐treatment for vacuum drying of orange slices: drying characteristics, rehydration capacity and quality properties. J. Food Process Eng. 43, e13511 (2020).
Surendhar, A., Sivasubramanian, V., Vidhyeswari, D. & Deepanraj, B. Energy and exergy analysis, drying kinetics, modeling and quality parameters of microwave-dried turmeric slices. J. Therm. Anal. Calorim. 136, 185–197 (2019).
Dehghannya, J., Ngadi, M. & Vigneault, C. Mathematical modeling procedures for airflow, heat and mass transfer during forced convection cooling of produce: a review. Food Eng. Rev. 2, 227–243 (2010).
Putra, R. N. & Ajiwiguna, T. A. Influence of air temperature and velocity for drying process. Procedia Eng. 170, 516–519 (2017).
Han, Y. et al. A novel microwave pretreated hot air drying (PMt-HD) process for improving drying efficiency and drying quality of Z. bungeanum. Ind. Crops Prod. 222, 119482 (2024).
Salehi, F., Goharpour, K. & Kamran, H. R. Effects of ultrasound and microwave pretreatments of Carrot slices before drying on the color indexes and drying rate. Ultrason. Sonochem. 101, 106671 (2023).
Karimi, S., Layeghinia, N. & Abbasi, H. Microwave pretreatment followed by associated microwave-hot air drying of Gundelia tournefortii L.: drying kinetics, energy consumption and quality characteristics. Heat Mass Transf. 57, 133–146 (2021).
Dbeibia, A., Khiari, R., Mihoubi, D., Zeghonda, N. & Boudhrioua, N. Drying kinetics of Deglet enour date Seeds, Antioxidant, Antibacterial, antidiabetic and Bio-preservative potencies. Waste Biomass Valoriz. 1–17 (2025).
Metwally, K. A. et al. The mathematical Modeling, Diffusivity, Energy, and Enviro-Economic analysis (MD3E) of an automatic solar dryer for drying date fruits. Sustainability 16, 3506 (2024).
Seerangurayar, T. et al. Experimental investigation and modeling of date drying under forced convection solar dryers. Biomass Convers. Biorefinery. 14, 21705–21718 (2024).
Rabie, S., Younis, O. S. & Mohamed, A. Kinetic studies for microwave-assisted drying of Oraby date slices. Egypt. J. Agricultural Res. 98, 670–689 (2020).
İZLİ, G. Total phenolics, antioxidant capacity, colour and drying characteristics of date fruit dried with different methods. Food Sci. Technol. 37, 139–147 (2017).
Younis, M. et al. Kinetics and mathematical models of date paste dried using a convective infrared dryer. Czech J. Food Sci. 42 (2024).
El-Mesery, H. S., Farag, H. A., Kamel, R. M. & Alshaer, W. G. Convective hot air drying of grapes: drying kinetics, mathematical modeling, energy, thermal analysis. J. Therm. Anal. Calorim. 148, 6893–6908. https://doi.org/10.1007/s10973-023-12195-0 (2023).
Chokngamvong, S. & Suvanjumrat, C. Study of drying kinetics and activation energy for drying a pineapple piece in the crossflow dehydrator. Case Stud. Therm. Eng. 49, 103351 (2023).
Şahin, U. & Öztürk, H. K. Comparison between artificial neural network model and mathematical models for drying kinetics of osmotically dehydrated and fresh figs under open sun drying. J. Food Process Eng. 41, e12804 (2018).
Prajapati, S., Shah, M. & Srivastava, S. Mass transfer behavior of Jamun (Indian Blackberry) slices using convective drying technique. J. Biosystems Eng. 50, 353–363. https://doi.org/10.1007/s42853-025-00270-3 (2025).
Srikiatden, J. & Roberts, J. S. Moisture transfer in solid food materials: A review of mechanisms, models, and measurements. Int. J. Food Prop. 10, 739–777 (2007).
Fikry, M. et al. Influence of ultrasonic pretreatment on drying and thermodynamic characteristics of Asian Seabass fish skin during air-frying process. J. Food Meas. Charact. 1–14 (2024).
Öztekin, Y. B., Aktaş, M., Dolgun, E. C., Bilim, H. C. & Sacilik, K. Drying kinetics and thermodynamic properties of Uzun pistachios dried by convective drying. J. Food Process. Preserv. 46, e17035 (2022).
Moreira, I. S. et al. Production of Kiwi snack slice with different thickness: drying kinetics, sensory and physicochemical analysis. Aust. J. Crop Sci. 12, 778–787 (2018).
Santos, N. C., Almeida, R. L. J., da Silva, G. M., Monteiro, S. S. & Andre, A. M. M. Effect of ultrasound pre-treatment on the kinetics and thermodynamic properties of guava slices drying process. Innovative Food Sci. Emerg. Technol. 66, 102507 (2020).
Rashid, M. T. et al. Multi-frequency ultrasound and sequential infrared drying on drying kinetics, thermodynamic properties, and quality assessment of sweet potatoes. J. Food Process Eng. 42, e13127 (2019).
Goneli, A., Correa, P. C., Oliveira, G. & Botelho, F. M. Water desorption and thermodynamic properties of Okra seeds. Trans. ASABE. 53, 191–197 (2010).
Kaleemullah, S. & Kailappan, R. Monolayer moisture, free energy change and fractionation of bound water of red chillies. J. Stored Prod. Res. 43, 104–110 (2007).
Fikry, M. et al. Kinetic modelling of moisture transfer and phytochemical properties in Longan seeds: impact of ultrasonic pretreatment and microwave drying process. Food Bioprocess Technol. 17, 5134–5151 (2024).
Doymaz, İ. Drying behaviour of green beans. J. Food Eng. 69, 161–165 (2005).
Page, G. E. Factors Influencing the Maximum Rates of Air Drying Shelled Corn in Thin Layers (Purdue University, 1949).
Rahman, M. S., Perera, C. O. & Thebaud, C. Desorption isotherm and heat pump drying kinetics of peas. Food Res. Int. 30, 485–491 (1997).
Doymaz, İ. Effect of pre-treatments using potassium metabisulphide and alkaline Ethyl oleate on the drying kinetics of apricots. Biosyst. Eng. 89, 281–287 (2004).
Lahsasni, S., Kouhila, M., Mahrouz, M. & Jaouhari, J. Drying kinetics of prickly Pear fruit (Opuntia ficus indica). J. Food Eng. 61, 173–179 (2004).
Acknowledgements
The authors gratefully acknowledge the support of the Department of Food and Nutrition Sciences, College of Agriculture and Food Sciences, and the Date Palm Research Center of Excellence, King Faisal University, Saudi Arabia.
Funding
This study was funded by the Deanship of Scientific Research, Vice Presidency for Graduate Studies and Scientific Research, King Faisal University, Saudi Arabia, under Grant No. KFU254194.
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Nashi Alqahtani contributed to data analysis, visualization, and manuscript editing and revision. Mohammad Fikry was responsible for conceptualization, experimental design, data analysis, visualization, and manuscript writing. All authors reviewed and approved the final version of the manuscript for publication.
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Alqahtani, N., Fikry, M. Impact of microwave pretreatment on drying kinetics, mass transfer and thermodynamic characteristics of Barhi dates during drying process. Sci Rep (2026). https://doi.org/10.1038/s41598-026-39727-6
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DOI: https://doi.org/10.1038/s41598-026-39727-6
