title: Phytosterol structured algae oil nanoemulsions and powders: improving antioxidant and flavor properties.
abstract: Algae oil, enriched with omega-3 long-chain polyunsaturated fatty acids (ω-3 LC-PUFA), is known for its health benefits. However, protection against lipid oxidation as well as masking of unpleasant fishy malodors in algae oil enriched foods is a big challenge to achieve. In this study, we firstly achieved a one-pot ultrasound emulsification strategy (alternative heating-homogenization) to prepare phytosterol structured thermosensitive algae oil-in-water nanoemulsion stabilized by quillaja saponin. After spray drying, the resulting algae oil powders from the structured nanoemulsion templates exhibit an excellent reconstructed behavior, even after 30 d of storage. Furthermore, an enhanced oxidative stability was obtained by reducing both the primary and secondary oxidation products through formulation with β-sitosterol and γ-oryzanol, which are natural antioxidants. Following the results of headspace volatiles using dynamic headspace-gas chromatography-mass spectrometry (DHS-GC-MS), it was clear that the structured algae oil-loaded nanoemulsion and powder had lower levels of fishy off-flavour (e.g., (Z)-heptenal, decanal, ethanone, and hexadecenoic acid), whereas the control emulsion and oil powder without structure performed worse. This study demonstrated that the structure from phytosterols is an effective strategy to minimize the fishy off-flavour and maximize oxidative stability of both algae oil nanoemulsions and spray-dried powders, and opens up the possibility of formulation design in polyunsaturated oil encapsulates as novel delivery systems to apply in functional foods and beverages.
authors: Research and Development Center of Food Proteins, Department of Food Science and Engineering, South China University of Technology, Guangzhou 510640, People's Republic of China. fexqyang@scut.edu.cn fexqyang@163.com.
authors: Xiao-Wei
authors: XW
authors: Chen
authors: Ya-Jun
authors: YJ
authors: Chen
authors: Jin-Mei
authors: JM
authors: Wang
authors: Jian
authors: J
authors: Guo
authors: Shou-Wei
authors: SW
authors: Yin
authors: Xiao-Quan
authors: XQ
authors: Yang
mesh_terms: D000975:Antioxidants / Q000032:analysis*; D004355:Drug Stability; D004655:Emulsions / Q000737:chemistry*; D015525:Fatty Acids, Omega-3 / Q000737:chemistry*; D005527:Food, Fortified; D009812:Odorants / Q000032:analysis; D009821:Oils / Q000737:chemistry*; D010666:Phenylpropionates; D010840:Phytosterols / Q000737:chemistry*; D011208:Powders; D062605:Quillaja Saponins; D012855:Sitosterols; D013649:Taste
chemical_list: D000975:Antioxidants; D004655:Emulsions; D015525:Fatty Acids, Omega-3; D009821:Oils; D010666:Phenylpropionates; D010840:Phytosterols; D011208:Powders; D062605:Quillaja Saponins; D012855:Sitosterols; C025473:gamma-sitosterol; C013172:gamma-oryzanol