Elmaların osmotik dehidrasyonunda kütle transferinin modellenmesi
Küçük Resim Yok
Tarih
1999
Yazarlar
Dergi Başlığı
Dergi ISSN
Cilt Başlığı
Yayıncı
Ege Üniversitesi
Erişim Hakkı
info:eu-repo/semantics/closedAccess
Özet
IV ÖZET ELMALARIN OSMOTİK DEHİDRASYONUNDA KÜTLE TRANSFERİNİN MODELLENMESİ SULTANOĞLU, Mustafa Yüksek Lisans Tezi, Gıda Mühendisliği Bölümü Tez Yöneticisi: Yrd. Doç. Dr. Figen KAYMAK ERTEKİN Ağustos 1999, 66 Sayfa Bu araştırmada elmaların sakkaroz, dekstroz ve sakkaroz-dekstroz karışımı çözeltiler içinde çeşitli konsantrasyon ve sıcaklıklarda osmotik dehidrasyon mekanizması incelenmiş ve işlem sırasındaki kütle transferini karakterize eden bazı modeller karşılaştınlmıştır. Konsantrasyon ve sıcaklık arttıkça elmalardan su kaybının önemli düzeyde arttığı bulgulanmıştır. Dekstroz-sakkaroz karışımı çözeltide ise aynı toplam kuru madde konsantrasyonunda dekstroz oranı arttıkça hem su kaybı hem de kuru madde kazanımının arttığı gözlenmiştir. Önerilen modellerden Azuara et al. (1992) modeli kullanılarak sonuç denge noktası ve osmotik dehidrasyon kinetiğini belirlemek mümkün olabilmektedir. Bu model deneysel verilerle oldukça iyi uyum göstermiştir. Kararsız rejim ikinci Fick difüzyon eşitliğinin nümerik olarak çözümlenmesiyle ise hem su kaybı hem de kuru madde kazanımına ilişkin difüzyon katsayıları hesaplanmıştır. Elde edilen difüzyon katsayıları 10"10-10"u m2/s mertebesinde ve literatürle uyumlu bulunmuştur
ABSTRACT MODELLING OF MASS TRANSFER DURING OSMOTIC DEHYDRATION OF APPLES SULTANO?LU, Mustafa M. Sc. in Food Eng. Supervisor: Yrd. Doç. Dr. Figen KAYMAK ERTEKİN August 1999, 66 pages In this thesis, the osmotic dehydration mechanism of apples in different concentrations of sucrose, dextrose and sucrose-dextrose mixed solutions and also at different temperatures were investigated and some models, which characterise the mass transfer along this process, were compared. It was recognised that as the concentration and temperature were increased, loss of water in apples was also increased at a considerable level. It was observed that, in sucrose-dextrose mixed solution having the same total dry matter concentration, both water loss and solid gain were increased, if the amount of dextrose in mixture was increased. By using Azuara et al. (1992) model among recommended models, it can be possible to predict the equilibrium point and the kinetics of osmotic dehydration. This model was found to best fit with the experimental values. By the numerical analysis of unsteady state second Fick diffusion equation, the diffusion coefficients related with both water loss and dry matter gain were calculated. The values of calculated diffusion coefficients were found to be in the range of 10"10-10"n m2/s which were in good accordance with literature values.
ABSTRACT MODELLING OF MASS TRANSFER DURING OSMOTIC DEHYDRATION OF APPLES SULTANO?LU, Mustafa M. Sc. in Food Eng. Supervisor: Yrd. Doç. Dr. Figen KAYMAK ERTEKİN August 1999, 66 pages In this thesis, the osmotic dehydration mechanism of apples in different concentrations of sucrose, dextrose and sucrose-dextrose mixed solutions and also at different temperatures were investigated and some models, which characterise the mass transfer along this process, were compared. It was recognised that as the concentration and temperature were increased, loss of water in apples was also increased at a considerable level. It was observed that, in sucrose-dextrose mixed solution having the same total dry matter concentration, both water loss and solid gain were increased, if the amount of dextrose in mixture was increased. By using Azuara et al. (1992) model among recommended models, it can be possible to predict the equilibrium point and the kinetics of osmotic dehydration. This model was found to best fit with the experimental values. By the numerical analysis of unsteady state second Fick diffusion equation, the diffusion coefficients related with both water loss and dry matter gain were calculated. The values of calculated diffusion coefficients were found to be in the range of 10"10-10"n m2/s which were in good accordance with literature values.
Açıklama
Bu tezin, veri tabanı üzerinden yayınlanma izni bulunmamaktadır. Yayınlanma izni olmayan tezlerin basılı kopyalarına Üniversite kütüphaneniz aracılığıyla (TÜBESS üzerinden) erişebilirsiniz.
Anahtar Kelimeler
Gıda Mühendisliği, Food Engineering, Dehidratasyon, Dehydration, Elma, Apple, Kütle aktarımı, Mass transfer, Meyveler, Fruits
