Akademik Veri Yönetim Sistemi
Tezin Türü: Yüksek Lisans
Tezin Yürütüldüğü Kurum: Orta Doğu Teknik Üniversitesi, Mühendislik Fakültesi, Gıda Mühendisliği Bölümü, Türkiye
Tezin Onay Tarihi: 2016
Öğrenci: ELİF AKBAŞ
Eş Danışman: ULVİYE BETÜL SÖYLER, HALİL MECİT ÖZTOP
Özet:In recent years, nanoemulsion based systems have been successfully used in food, medical and pharmaceutical applications as effective lipophilic carrier systems for nutraceuticals, drugs, antioxidants and antimicrobial agents. The primary active ingredient of chili pepper, capsaicin is a hydrophobic substance and was proved to be a compound showing good antimicrobial activity against various microorganisms. The aim of the proposed study was to prepare and characterize capsaicin loaded nanoemulsion systems. Nanoemulsions were prepared with emulsifiers Tween 80, lecithin and sucrose monopalmitate (SMP) by using microfluidization and ultrasonication at pH 7.4 and pH 3.8. Effect of glycerol addition and heating the coarse dispersions on nanoemulsion formation were also investigated. Antimicrobial activities of nanoemulsions were evaluated against well-known food pathogens Escherichia coli and Staphylococcus aureus. In the experiments, 2% capsaicin nanoemulsions decreased E.coli population up to 3.4 log after 15 min of contact time by using lecithin and S. aureus population up to 5.89 log after 2 hours of contact time by using Tween 80. The smallest particle size of 33.17 nm was obtained using SMP with microfluidization. Addition of glycerol to the continuous phase showed enhanced effect on the results for both homogenization types. Moreover, nanoemulsions processed by microfluidization exhibited enhanced physical properties and antimicrobial activity. NMR relaxometry technique helped to track changes in nanoemulsions that was associated with the other methods such as particle size, turbidity. In overall, nanoemulsions with improved functionality were obtained using capsaicin.