Akademik Veri Yönetim Sistemi
Tezin Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Gıda Mühendisliği Bölümü, Türkiye
Tezin Onay Tarihi: 2019
Öğrenci: Eda Ceren Kaya
Danışman: HAMİ ALPAS
Özet:Chia seed is a good source of not only protein, dietary fiber and antioxidants but also polyunsaturated fatty acids, which are in higher amounts compared to other seedbased food sources. Nanoemulsions are colloidal dispersions that contain small particles, typically around 20-200 nm in diameter, that may not be distinctively visible since they do not scatter light strongly. Moreover, they have strong stability and can protect the embedded oil from oxidation. Thus, utilization of nanoemulsions from chia seed oil arouses interest among researchers. In this study, oil was extracted from grinded chia seed using conventional extraction methods and high pressure assisted extraction. In addition to oil extraction, chia oil nanoemulsions were prepared using spontaneous emulsification (0.5, 1, 1.25, 1.5, 2.5 and 3 % (w/w)). For chia oil emulsions, particle size analysis, antioxidant activity by DPPH and FRAP, total phenolic content by Folin Ciocalteu, peroxide value, determination of secondary oxidation products by TBARS, oil-water interaction by NMR Relaxometry, instantaneous and long term stability experiments were conducted. Also, HHP was applied to emulsion in order to see the coalescence mechanism. According to results obtained, emulsion systems showed better antioxidant activity and phenolic content than oil samples. In addition to this, among the emulsions, the best antioxidant activity, phenolic content and oxidative stability was found in the emulsion having 2.5 % (w) chia oil. This study showed that formation of nanoemulsions helped to improve the bioavailability and bioactivity.