A COMPARATIVE STUDY BETWEEN FRESH AND DRIED WALNUT BASED ON INDUSTRIAL PROCESSING

Abstract

Post-harvest processes of walnuts in the industry are preliminary before consumption. In this study, the dimensions, nut density, terminal velocity, drag coefficient, color, oil quality, protein content, water permeation pathway, and microstructure variation of the fresh and dried walnut samples were researched. The results indicated that every physical and aerodynamic property of fresh samples (except drag coefficient) was a higher value than dried walnuts. In terms of total color difference, the difference was calculated as 6.3. However, no significant (p<0.05) difference was determined between samples in AV, PV, and protein content. By comparison of scanning electron microscopy images, both fresh and dried walnut kernels of the surface had a smooth surface and no apparent porous structure. In conclusion, it was determined that the industrial drying method did not affect the internal structure while affecting the external structure.

Keywords

• dimensions
• color
• oil
• quality

Supporting Institution

TÜBİTAK-2219 Yurt Dışı Doktora Sonrası Araştırma Burs Programı

Project Number

1059B192000976

Thanks

We (Onur TASKIN and Zhongli PAN) thank TUBITAK for funding the project.

ENDÜSTRİYEL İŞLEME ESASLI TAZE VE KURU CEVİZİN KARŞILAŞTIRILMASI

Abstract

Endüstride cevizin hasat sonrası işlemleri tüketim öncesinde ön hazırlık niteliğindedir. Bu çalışmada taze ve kurutulmuş ceviz örneklerinin boyutları, tane yoğunluğu, kritik hızı, sürtünme katsayısı, rengi, yağ kalitesi, protein içeriği, su geçirgenlik yolu ve mikroyapı değişimleri araştırılmıştır. Sonuçlar taze ceviz örneklerinin tüm fiziksel ve aerodinamik özelliklerinin (sürtünme katsayısı hariç) kuru cevizlere göre daha yüksek değerde olduğunu göstermiştir. Toplam renk farkı 6.3 olarak hesaplanmıştır. Ancak yağ kalitesi ve protein içeriği açısından örnekler arasında anlamlı bir fark saptanmamıştır (p<0.05). Taramalı elektron mikroskopu görüntüleri karşılaştırıldığında, hem taze hem de kurutulmuş ceviz yüzeyinin pürüzsüz bir yapıya sahip olduğu ve belirgin gözenekli bir yapıya sahip olmadığı görülmüştür. Sonuç olarak, endüstriyel kurutma yönteminin dış yapıyı etkilerken içyapıyı etkilemediği tespit edilmiştir.

Keywords

• Boyut
• renk
• yağ
• kalite

Project Number

1059B192000976

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