Encapsulation of wheat germ oil


Tezin Türü: Yüksek Lisans

Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Gıda Mühendisliği Bölümü, Türkiye

Tezin Onay Tarihi: 2013

Öğrenci: BAŞAK YAZICIOĞLU

Eş Danışman: SERVET GÜLÜM ŞÜMNÜ, SERPİL ŞAHİN

Özet:

Wheat germ oil is a rich source of omega 3 and omega 6, octacosanol and tocopherol which has vitamin E activity. Due to these properties it is beneficial for health but it is prone to oxidation in free form. The aim of this study was to encapsulate wheat germ oil in micron size and determine the best encapsulation conditions by analysing encapsulation efficiency, particle size distribution and surface morphology of the capsules. The effects of core to coating ratio, coating materials ratio and ultrasonication time on encapsulation of wheat germ oil were investigated. Maltodextrin (MD) and whey protein concentrate (WPC) at different ratios (3:1, 2:2, 1:3) were used as coating materials. Total solid content of all samples was 40% (w/w). Five different core to coating ratios (1:8, 1:4, 2:4, 3:4, 4:4) were experimented. Ultrasound was used at 320 W and 20 kHz frequency for three different times (2, 5, 10 min). Prepared emulsions were frozen and then freeze dried for 48 hours to obtain microcapsules. Encapsulation efficiency analysis, particle size analysis and scanning electron microscopy (SEM) analysis were performed. Increasing WPC content in coating led to an increase in encapsulation efficiency. Microcapsules prepared with MD:WPC ratio of 1:3 were found to have higher encapsulation efficiencies (65.62%-89.62%) than the other ratios. Increase in oil load led to decrease in encapsulation efficiency thus 1:8 core to coating ratio gave better results. The best conditions for microcapsules were determined as ultrasonication time 10 min, core to coating ratio of 1:8 and MD:WPC ratio 1:3.