| Author | Nuntarat Baoonlao |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Science in Food Engineering and Bioprocess Technology, SERD |
| Publisher | Asian Institute of Technology |
| Abstract | This study aims to evaluate the effects of whey protein isolate (WP!) and xanthan gum
(XG) stabilized oil-in-water emulsions loaded with astaxanthin for their physicochemical
stability and in-vitro gastrointestinal tract behavior. The formulations of emulsions with
different WP! and XG concentrations were evaluated. Whey protein isolate concentration
was varied from 2 to 5 wt%, while XG was varied from 0 to 0.5 wt%. The result showed
that the additions of 0.5 wt% XG with all different WP! concentrations increased the
viscosity, reduce creaming and the phase separations. Fmthennore, the emulsion with 0.5
wt% XG did not exhibit any phase separation during the storage period of 30 days. The
astaxanthin-loaded emulsions were fmiher evaluated for the influences of temperature, pH,
ionic concentration and light. Emulsions were found physically stable up to 70 °c. The
retention of astaxanthin after processing conditions based on pasteurization was
determined at 63 °c and 72 °c under different intervals of time. The retention of
astaxanthin was around 80% after heating at 63 °c during 15, 30 and 45 min. However, the
highest astaxanthin retention (98%) was found under 72 °c for 15 min. The emulsions
were not stable at pH 2-4. Futihermore, emulsions were found physically stable under the
different salt concentrations, in the ranges of 0-150 mM. The astaxanthin retention of
emulsion exposure to light condition is 78 % over 32 h. Additional, emulsions with WPI
and WPI+ XG were assessed through an in-vitro gastrointestinal model and changes in their
particle size, zeta potential were evaluated. The bioaccessibility of astaxanthin
incorporated into WPI-stabilized emulsion and emulsion with WPI+ XG is 46.2 % and 12.6
% respectively. |
| Year | 2018 |
| Type | Thesis |
| School | School of Environment, Resources, and Development (SERD) |
| Department | Department of Food, Agriculture and Natural Resources (Former title: Department of Food Agriculture, and BioResources (DFAB)) |
| Academic Program/FoS | Food Engineering and Bioprocess Technology (FB) |
| Chairperson(s) | Anal, Anil Kumar; |
| Examination Committee(s) | Loc Thai Nguyen ;Sadiq, Muhammad Bilal ;Uracha Ruktanonchai ; |
| Scholarship Donor(s) | Her Majesty the Queen's Scholarships; |