Osmotic Pretreatment and Solar Drying of Eggplant in Tunisian Rural Areas: Assessing the Impact of Process Efficiency and Product Quality
Abstract
1. Introduction
2. Materials and Methods
2.1. Raw Material and Sample Pretreatment
2.2. Solar Drying and Drying Kinetics
2.3. Rehydration Capacity
2.4. Physicochemical Properties
2.5. Textural Properties
2.6. Thermal Properties
2.7. Statistical Analysis
3. Results and Discussion
3.1. Drying Kinetics
3.2. Rehydration Capacity
3.3. Physicochemical Properties
3.4. Textural and Thermal Properties
4. Conclusions
Author Contributions
Funding
Data Availability Statement
Conflicts of Interest
References
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Eggplant Samples | ||||
---|---|---|---|---|
Parameters | Fresh | Dried | Salted Dried | p-Value |
Moisture (%) | 92.40 ± 0.52 a | 13.58 ± 0.27 b | 9.39 ± 0.09 c | <0.001 |
aw | 0.984 ± 0.007 a | 0.554 ± 0.007 c | 0.539 ± 0.002 b | <0.001 |
Protein (% DM) | 0.94 ± 0.01 c | 9.08 ± 1.95 a | 5.11 ± 0.12 b | <0.001 |
Crude fat (% DM) | 1.35 ± 0.56 a | 0.20 ± 0.01 b | 0.33 ± 0.20 b | 0.003 |
Ash (% DM) | 0.64 ± 0.02 c | 5.62 ± 0.17 b | 7.93 ± 0.89 a | <0.001 |
Carbohydrates (% DM) | 4.80 ± 0.85 c | 79.56 ± 0.01 a | 69.22 ± 3.12 b | <0.001 |
Vitamin C (% DM) | 1.11 ± 0.07 a | 0.84 ± 0.01 c | 0.97 ± 0.00 b | <0.001 |
Potassium (mg/kg) | 1951.30 ± 333 c | 30,890.43 ± 2115 a | 17,104.47 ± 818 b | <0.001 |
Parameters | Eggplant Samples | |||
---|---|---|---|---|
Fresh | Dried | Salted Dried | p-Value | |
Texture | ||||
Hardness (N) | 4.51 ± 2.33 b | 6.19 ± 2.60 ab | 11.15 ± 4.60 a | 0.036 |
Adhesive force (N) × 10−3 | −2.92 ± 0.002 | −4.75 ± 0.001 | −4.69 ± 0.002 | 0.228 |
Elastic force (N/mm2) | 0.042 ± 0.006 | 0.039 ± 0.012 | 0.054 ± 0.017 | 0.214 |
Thermal properties (°C) | ||||
Ti | 102.05 | 100.78 | ||
Tp | 107.44 | 107.38 | ||
Tf | 107.85 | 107.77 |
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Jribi, S.; Essaidi, I.; Ben Rejeb, I.; Ghanem, R.; Hamza, M.E.; Khamassi, F. Osmotic Pretreatment and Solar Drying of Eggplant in Tunisian Rural Areas: Assessing the Impact of Process Efficiency and Product Quality. Processes 2025, 13, 2442. https://doi.org/10.3390/pr13082442
Jribi S, Essaidi I, Ben Rejeb I, Ghanem R, Hamza ME, Khamassi F. Osmotic Pretreatment and Solar Drying of Eggplant in Tunisian Rural Areas: Assessing the Impact of Process Efficiency and Product Quality. Processes. 2025; 13(8):2442. https://doi.org/10.3390/pr13082442
Chicago/Turabian StyleJribi, Sarra, Ismahen Essaidi, Ines Ben Rejeb, Raouia Ghanem, Mahmoud Elies Hamza, and Faten Khamassi. 2025. "Osmotic Pretreatment and Solar Drying of Eggplant in Tunisian Rural Areas: Assessing the Impact of Process Efficiency and Product Quality" Processes 13, no. 8: 2442. https://doi.org/10.3390/pr13082442
APA StyleJribi, S., Essaidi, I., Ben Rejeb, I., Ghanem, R., Hamza, M. E., & Khamassi, F. (2025). Osmotic Pretreatment and Solar Drying of Eggplant in Tunisian Rural Areas: Assessing the Impact of Process Efficiency and Product Quality. Processes, 13(8), 2442. https://doi.org/10.3390/pr13082442