Thin-layer modeling, drying parameters, and techno-enviro-economic analysis of a solar dried salted tilapia fish fillets

Tarek Hussien M Ghanem; Loai S Nsasrat; Omar Shahat Younis; Khaled A Metwally; Ali Salem; Zoltan Orban; Mohamed Hamdy Eid; Hany S El-Mesery; Abdalla Zain Eldin; Khaled Mohamad Elmolakab; Samy F Mahmoud; Abdallah Elshawadfy Elwakeel

doi:10.1038/s41598-025-87807-w

Thin-layer modeling, drying parameters, and techno-enviro-economic analysis of a solar dried salted tilapia fish fillets

Sci Rep. 2025 Feb 11;15(1):5073. doi: 10.1038/s41598-025-87807-w.

Authors

Affiliations

¹ Agricultural Products Processing Engineering Department, Faculty of Agricultural Engineering, Al Azhar University, Cairo, Egypt.
² Electrical Power Engineering Department, Faculty of Engineering, Aswan University, Aswan, 81528, Egypt.
³ Food Manufacturing Engineering and Packaging Department, Food Technology Research Institute, Agriculture Research Center, Giza, Egypt.
⁴ Soil and Water Sciences Department, Faculty of Technology and Development, Zagazig University, Zagazig, 44519, Egypt.
⁵ Civil Engineering Department, Faculty of Engineering, Minia University, Minia 61111, Egypt. salem.ali@mik.pte.hu.
⁶ Structural Diagnostics and Analysis Research Group, Faculty of Engineering and Information Technology, University of Pécs, Pécs 7622, Hungary. salem.ali@mik.pte.hu.
⁷ Structural Diagnostics and Analysis Research Group, Faculty of Engineering and Information Technology, University of Pécs, Pécs 7622, Hungary.
⁸ Institute of Environmental Management, Faculty of Earth Science, University of Miskolc, Miskolc-Egyetemváros, 3515, Hungary.
⁹ Geology Department, Faculty of Science, Beni-Suef University, Beni-Suef, 65211, Egypt.
¹⁰ School of Energy and Power Engineering, Jiangsu University, Zhenjiang, 212013, China.
¹¹ Agricultural Engineering Research Institute, Agricultural Research Center, Giza, 12611, Dokki, Egypt.
¹² Agricultural and Biosystems Engineering Department, Faculty of Agriculture, Alexandria University, Alexandria, Egypt.
¹³ Agricultural Engineering Department, Faculty of Agriculture and Natural Resources, Aswan University, Aswan, Egypt.
¹⁴ Department of Biotechnology, College of Science, Taif University, Taif City, Saudi Arabia. s.farouk@tu.edu.sa.

Abstract

This study focused on the development of an indirect forced solar dryer that incorporates a three-sided flat plate solar collector (TSFPSC) specifically designed for increasing thermal efficiency, and the system used for drying salted tilapia fish fillets (STFF). The investigation analyzed three fillet thicknesses-4 mm, 8 mm, and 12 mm, employing both open sun drying (OSD) and the developed solar dryer (DSD), with a constant airspeed of 0.5 m/s. The research additionally developed thin-layer drying models (TLDM), assessed drying parameters, and performed an extensive techno-enviro-economic analysis. Results showed that the initial and final moisture content (MC) (w.b. %) of the STFF were 74.83 and 18.84%, respectively, and reached the equilibrium MC after 16-20.5 h for the DSD and 30-36 h for the OSD, which means the drying time reduced by about 53.3%, and 61.11% compared with the OSD. This reduction in drying time demonstrates the effectiveness of the developed solar dryer. The effective moisture diffusivity (EMD) of different STFF samples at both drying systems were 0.51 × 10^-10 to 9.16 × 10^-10 m²/s. In addition, all eleven basic TLDM were applied to predict the drying behavior of STFF during the drying process, while the combined Two-Term and Page model had the best fitting for the OSD system, and the modified Midilli II model and combined Two-Term and Page model had the best fitting for the DSD system. In terms of economic analysis, the annual capital and investment costs were calculated to be $22.458 and $21.334, respectively. Additionally, the environmental analysis indicated an energy payback (EP) period of 1.59 years, with a net CO₂ mitigation of 14 tons realized over the operational lifetime of the DSD.

Keywords: Carbon footprint; Effective moisture diffusivity greenhouse gas; Fish; Mathematical modeling; Solar drying; Solar energy.

MeSH terms

Animals
Desiccation* / methods
Food Preservation* / economics
Food Preservation* / methods
Solar Energy
Sunlight
Tilapia*