Abstract
The hybrid solar smart dryer (HSSD) was established to dry medicinal and aromatic herbs that are sensitive to direct sunlight. This study explores the effectiveness of the HSSD as an indirect solar drying technique in drying lemongrass, thyme, marjoram, and lavender at different temperatures (30, 40, and 50 ± 2 °C), focusing on its ability to retain quality features. The total energy consumption was estimated by values of 27.72 kWh for lemongrass and 43.02 kWh for lavender using HSSD at 50 ± 2 °C. Generally, HSSD showed an improvement in the studied physicochemical quality parameters. The green color retention was with the parameters of 15.60 ± 0.89, −5.28 ± 1.92, −3.89 ± 1.86, and −5.89 ± 2.40 for lemongrass, thyme, marjoram, and lavender samples, respectively. The highest values of the lemon grass, thyme, marjoram, and lavender oil content (1.96, 1.73, 3.40, and 2.76%, respectively) were obtained when the aromatic herbs were dried using the HSSD at 40 °C. This study showcased the effectiveness of solar dryers in preserving the physicochemical properties of lemongrass, thyme, marjoram, and lavender during drying, which could be applied to other food products. HSSD is a promising energy-efficient method that can save 19–36% of energy consumption, reducing the carbon footprint of drying processes and delivering high-quality products.
Acknowledgment
The authors are grateful to the Agricultural Engineering Research Institute (AEnRI), and Horticulture Research Institute, the Agricultural Research Center (ARC), Egypt, and the Science, Technology & Innovation Funding Authority (STDF) for supporting the project team.
Author contributions
Alia Amer, Ayman Ibrahim, Islam Elsebaee: Conceptualization; Data curation; Formal, analysis; Investigation; Methodology; Project administration; Writing-original draft; Writing-review and editing. Aml Shahin, Rasha Saad, Zeinab Hassan, Mohamed Fathi: Data curation; Investigation; Methodology.
Disclosure statement
The authors have declared no conflicts of interest for this article.
Data availability statement
The authors confirm that the data supporting the findings of this study are available within the article. Also, fully prepared to cooperate by making the data available at reasonable request.