Effect of Solar Collector Geometry on Drying Time and Nutritional Properties of Levant Quality Hazelnuts

Abstract

This study examines the impact of drying Levant quality hazelnut samples, including husk and shell, using hot air heated by solar panels at a constant speed of 6 m/s. The study also investigates the impact of collector irradiation absorption surface geometries on hazelnut drying time. A solar collector with four types of air duct geometry was used to dry hazelnuts. The radiation-absorbing surface of the air duct was manufactured flat, and three different trapezoidal geometries (30, 45 and 60 angles) were used. The mass losses of hazelnuts were measured and determined at regular intervals. In addition, the total phenolic content, the DPPH radical scavenging activity, the FRAP, the free fatty acid content, the peroxide value and the moisture content were measured. For the purpose of comparison, some of the products have been dried by means of unheated air at ambient temperature. The pre-drying process (withering process) to separate the hazelnuts from husk, only took 1.5 days (14 h excluding night). In these systems, the shelled fresh hazelnuts, separated from the husk, fell below the equilibrium moisture content of 6% in 2 days (except for 18 h at night). It was found that the most suitable collector geometry for all the parameters studied in the drying of hazelnuts with solar collectors was 45 degrees, and that other geometries could be used in terms of food properties.

Keywords

• Drying
• Solar collector
• Hazelnut traits
• Husk

Effect of Solar Collector Geometry on Drying Time and Nutritional Properties of Levant Quality Hazelnuts

Abstract

This study examines the impact of drying Levant quality hazelnut samples, including husk and shell, using hot air heated by solar panels at a constant speed of 6 m/s. The study also investigates the impact of collector irradiation absorption surface geometries on hazelnut drying time. A solar collector with four types of air duct geometry was used to dry hazelnuts. The radiation-absorbing surface of the air duct was manufactured flat, and three different trapezoidal geometries (30, 45 and 60 angles) were used. The mass losses of hazelnuts were measured and determined at regular intervals. In addition, the total phenolic content, the DPPH radical scavenging activity, the FRAP, the free fatty acid content, the peroxide value and the moisture content were measured. For the purpose of comparison, some of the products have been dried by means of unheated air at ambient temperature. The pre-drying process (withering process) to separate the hazelnuts from husk, only took 1.5 days (14 h excluding night). In these systems, the shelled fresh hazelnuts, separated from the husk, fell below the equilibrium moisture content of 6% in 2 days (except for 18 h at night). It was found that the most suitable collector geometry for all the parameters studied in the drying of hazelnuts with solar collectors was 45 degrees, and that other geometries could be used in terms of food properties.

Keywords

• Drying
• Solar collector
• Hazelnut traits
• Husk

References

1. Akgün M, Akgün M. 2023. Effect of solar collector drying on the nutritional properties of Çakıldak hazelnut. Turkish J Food Agri Sci, 5(2): 130-140.
2. Akgün M, Kandemir L, Öztürk B. 2018. Effect of led drying on drying behavior of Prunus domestica L. fruit. Indian J Pharmac Edu Res, 52(4): 115-118.
3. Aksüt B, Dinçer E, Saraçoğlu O, Polatcı H. 2023. Kurutma yöntemi ve sıcaklık değerlerinin mor reyhanın kuruma kinetiği ve renk kalitesi üzerine etkisi. Anad Tarım Bilim Derg, 38 (1): 187-198.
4. Aktaş M. 2003. Optimization of fins in indirect hot water preparation systems with solar energy natural circulation. MSc thesis, Gazi University Institute of Science and Technology, Ankara, Türkiye, pp: 53-99.
5. AOAC. 1990. Oils and fats official methods of analysis of the association of official analytical chemists. Washington DC, US, pp: 485-518.
6. Balık HI, Balık SK, Duyar Ö. 2021. Hazelnut genetic resources project. 2nd International Cukurova Agriculture and Veterinary Congress, January 4-5, Adana, Türkiye, p: 75-76.
7. Balık HI. 2021. Bioactive compounds and fatty acid composition of new Turkish hazelnut cultivars. Int J Fruit Sci, 21(1): 106-114.
8. Behera DD, Mohanty AM, Mohanty RC. 2022. Recent advances in solar drying technologies: A Comprehensive review. JES, 6(4): 503-519.

9. Benzie IF, Strain JJ. 1996. The ferric reducing ability of plasma (FRAP) as a measure of “antioxidant power”: the FRAP assay. Analytical Biochem, 239(1): 70-76.
10. Brand-Williams W, Cuvelier ME, Berset CLWT. 1995. Use of a free radical method to evaluate antioxidant activity. LWT-Food Sci Technol, 28(1): 25-30.
11. Çelik ÖF. Aktaş N, Tugay Mİ, Tunçil YE. 2023. Hazelnut (Corylus avellana L.) skin, a by‐product of hazelnut industry, possesses oil with high oxidative and thermal stabilities. Int J Food Sci Technol, 58(10): 5471-5477.
12. Ceylan İ, Aktaş M, Doğan H. 2006. Apple drying in a solar drying oven. Polytechnic J, 9(4): 289-294.
13. Danso-Boateng E. 2013. Effect of drying methods on nutrient quality of Basil (Ocimum viride) leaves cultivated in Ghana. Inter Food Res J, 20(4): 1569-1573.
14. Demirtaş C. 1996. Fındık kurutma şartlarının belirlenmesi. PhD Thesis, Institute of Science and Technology, Karadeniz Technical University, Trabzon, Türkiye, pp: 151.
15. EL-Mesery HS, EL-Seesy AI, Hu Z, Li Y. 2022. Recent developments in solar drying technology of food and agricultural products: A review. Renew Sustain Energy Rev, 157: 112070.
16. Fernandes L, Tavares PB. 2024. A review on solar drying devices: Heat transfer, air movement and type of chambers. Solar, 4(1): 15-42.
17. Genç S, Soysal Mİ. 2018. Parametric and nonparametric post hoc tests. BSJ Eng Sci, 1(1): 18-27.
18. Ghirardello D, Contessa C, Valentini N, Zeppa G, Rolle L, Gerbi V, Botta R. 2013. Effect of storage conditions on chemical and physical characteristics of hazelnut (Corylus avellana L.). Postharvest Biol Technol, 81: 37-43.
19. Harini, S, Kavya, VS, Ramana, AS. 2022. Recent developments in design and operations of solar dryer. IOP Conference Series: Earth and Environmental Science, 1100: 012007.
20. Huang D, Yang P, Tang X, Luo L, Sunden B. 2021. Application of infrared radiation in the drying of food products. Trends Food Sci Technol, 110: 765-777.
21. Karaosmanoğlu H. 2022. Lipid characteristics, bioactive properties, and mineral content in hazelnut grown under different cultivation systems. J Food Proces Preserv, 46(7): e16717.
22. Kashaninejad M, Tabil LG, Mortazavi A, Safe Kordi A. 2003. Effect of drying methods on quality of pistachio nuts. Drying Technol, 21(5): 821-838.
23. Kian-Pour N. 2020. Fundamental drying techniques applied in food science and technology. Int J Food Eng Res, 6(1): 35-63.
24. Köksal AI. 2002. Turkish hazelnut cultivars. Hazelnut Promotion Group, Ankara, Türkiye, pp: 136.
25. Kontaş E. 2022. Periyodik kurutma şartlarının fındığın kurutma davranışına etkisi. MSc Tthesis, Institute of Science and Technology, Ordu University, Ordu, Türkiye, pp: 71.
26. Memur E. 2022. Drying performance evaluations with solar food dryer design. Yekarum, 7(2): 48-57.
27. Mohana Y, Mohanapriya R, Anukiruthika T, Yoha KS, Moses JA, Anandharamakrishnan C. 2020. Solar dryers for food applications: Concepts, designs, and recent advances. Solar Energy, 208: 321-344.
28. Mokhtarian M, Tavakolipour H. 2019. The effects of solar drying systems and packaging types on the quality indicators of dried pistachio nuts. Pistachio Health J, 2(1): 71-82.
29. Özçağıran R, Ünal A, Özeker E, İsfendiyaroğlu M. 2014. Temperate climate fruit species. Ege University Press House, No: 566, İzmir, Türkiye, pp: 262.
30. Özcan MM, Uslu N. 2023. Investigation of changes in total phenol, flavonoid, antioxidant activity, fatty acids, polyphenol and mineral profiles of hazelnut kernels dried in air, oven and microwave. JSFA Rep, 3(2): 72-81.
31. Re R, Pellegrini N, Proteggente A, Pannala A, Yang M, Rice-Evans C. 1999. Antioxidant activity applying an improved ABTS radical cation decolorization assay. Free Radical Biol Medic, 26(9-10): 1231-1237.
32. Reddy TA. 1987. The design and sizing of active solar thermal systems. Oxford University Press, New York, US, pp: 4-10.
33. Saleh SM, Gatea AA. 2010. Design, construction, and performance evaluation of solar maize dryer. Iraqi J Mechan Mater Eng, 10(3): 365-376.
34. Shariah A, Al-Akhras M-Ali, Al-Omari IA. 2002. Optimizing the tilt angle of solar collectors. Renew Energy, 26: 587-598.
35. Simsek A, Artik N, Konar N. 2017. Phenolic profile of meals obtained from defatted hazelnut (Corylus avellana L.) varieties. Int J Life Sci Biotechnol Pharma Res, 6(1): 7-12.
36. Singleton VL, Orthofer R, Lamuela-Raventós RM. 1999. Analysis of total phenols and other oxidation substrates and antioxidants by means of Folin-ciocalteu reagent. Methods Enzymol, 299: 152-178.
37. Topdemir A. 2019. Mikroçoğaltımla üretilmiş fesleğenin (Ocimum basilicum L.) tepsili kurutucuda kuruma karakteristiğinin belirlenmesi. Fırat Üniv Müh Bilim Dergi, 31(2): 545-550.
38. TÜİK 2021. https://data.tuik.gov.tr/Kategori/GetKategori?p=tarim-111&dil=1 (accessed date: January 21, 2023).
39. Turan A, İslam A. 2018. Effect of drying methods on some chemical characteristics of hazelnuts (Corylus avellana L.) during storage. J Inst Sci Technol, 8(3): 11-19.
40. Turan A. 2018a. Effect of drying methods on fatty acid profile and oil oxidation of hazelnut oil during storage. European Food Res Technol, 244(12): 2181-2190.
41. Turan A. 2018b. Effect of drying methods on nut quality of hazelnuts (Corylus avellana L.). J Food Sci Technol, 55(11): 4554-4565.
42. Uzundumlu AS, Bilgiç A, Ertek N. (2019. Forecasting hazelnut production of Turkey's leading hazelnut producing provinces between 2019 and 2025 with ARIMA model. Acad J Agri, 8(Special Issue): 115-126.
43. Yaman M, Balta MF, Karakaya O, Kaya T, Necas T, Yildiz E, Dirim E. 2023. Assessment of fatty acid composition, bioactive compounds, and mineral composition in hazelnut genetic resources: Implications for nutritional value and breeding programs. Horticulturae, 9(9): 1008.
44. Yıldız Z, Gökayaz L. 2019. Drying of apple slices with different solar drying methods. J Food Feed Sci Technol, 22: 29-36.
45. Yılmaz M, Karakaya O, Balta MF, Balta F, Yaman İ. 2019. Change of biochemical characteristics depending on kernel size in Çakıldak hazelnut cultivar. Acad J Agri, 8(Special Issue): 61-70.