TitleImproving health-promoting effects and stability of food ingredients using nanoencapsulation
NameWang, Yuwen (author), HUANG, QINGRONG (chair), Lee, Tung-Ching (internal member), HO, CHI-TANG (internal member), HUANG, MOU-TUAN (outside member), Rutgers University, Graduate School - New Brunswick,
DescriptionThe stability and bioavailability of food ingredients and foods fortified with functional ingredients has long been an issue. In this thesis, nanoemulsion-based delivery systems were used to improve health-promoting effects and stability of food ingredients. First, nanoemulsions, including solid lipid nanoemulsions, stabilized by Tween 20 and glycerol monooleate, lecithin, or modified starch were developed. The average particle size of nanoemulsions with sufficient emulsifiers (Tween 20 and glycerol monooleate) and energy input can reach 60.5 nm. The nanoemulsion system has been further proved to improve bioavailability of dibenzoylmethane by 2.95-fold, compared to that of conventional emulsions. Curcumin, a polyphenol compound extracted from turmeric powders, possesses a variety of health-promoting effects but has extremely low bioavailability, mainly due to limited solubility. A dry curcumin emulsion system was developed combining solvent displacement, emulsification, and freeze-drying technology. Two ug/ml of encapsulated curcumin decreased viability of HepG2 cells to 52% (100% by DMSO-dissolved curcumin); 13.69 mg/ml of encapsulated curcumin inhibited 71% of TPA-induced inflammation of mice ears (none by DMSO-dissolved curcumin). HPLC showed that the encapsulated curcumin was stable for at least two months. FTIR and DSC studies suggested that lower crystallinity of encapsulated curcumin contributed to the enhanced activities of encapsulated curcumin. Stability is another issue to be addressed. Citral, derived from citrus fruits, is one of the most important flavor ingredients in the food industry, but it is very susceptible to oxidation and off-flavor generation at acidic environment, in which citral is most often used. The modified-starch-based solid lipid nanoemulsion system was used to stabilize citral. For comparison, two emulsions stabilized either by Tween 20/glycerol monooleate or modified starch were also used to encapsulate citral. The results showed that the citral stability was best retained if encapsulated in solid lipid nanoemulsions, and the off-flavor generation was best inhibited by using thick emulsifiers such as modified starch. In the thesis, it was proved that the nanoemulsion and its variations improve the health-promoting effects of insoluble nutraceuticals and the stability of delicate food ingredients.
NoteIncludes bibliographical references
Noteby Yuwen Wang
CollectionGraduate School - New Brunswick Electronic Theses and Dissertations
Organization NameRutgers, The State University of New Jersey
RightsThe author owns the copyright to this work.