The health benefits of carotenoids in terms of their role in decreasing the risk of diseases, particularly certain cancers and eye disease, are limited by their chemical degradation. Emulsion delivery systems with water dispersions of a carotenoid enhance chemical stability and bioavailability to the host. An emulsified carotenoid delivery system can be based on carotenoid dissolution in lipid media and its stabilization by a surfactant mixture of milk proteins (the caseins) and phospholipids. The inclusion of lutein into an emulsified delivery system comprised of bovine casein or caprine casein in combination with phospholipids (soybean lecithin) enhanced the chemical stability of lutein during storage for 7 days at pH 7.0 at incubation temperatures of 5 and 15°C. The chemical stability of lutein in the corn oil-in-water emulsions stabilized by bovine and caprine caseins in combination with soybean lecithin was in the following order: caprine αs1-II-casein/lecithin > caprine αs1-I-casein/lecithin > bovine casein/lecithin. The results suggest that the chemical stability of lutein in oil-in-water emulsions can be enhanced by altering the thickness of the interfacial layer. Caprine casein/lecithin has the potential for use as an emulsifier in beverage emulsions.
Part of the book: Progress in Carotenoid Research
Food emulsions undergo oxidative deterioration during production and storage, which is usually initiated from the unsaturated fatty acids. Synthetic antioxidants are frequently used to retard lipid oxidation in food emulsions. Most plants and their seeds are rich sources of natural antioxidants such as the carotenoids and polyphenols. The most abundant fatty acids found in the oil from the seeds of Hibiscus mutabilis (HM) are oleic acid (C18:1n-9, 16.3%), linoleic acid, (C18:2n-6, 64.7%), and palmitic acid (C16:0, 18.8%). The total tocopherols in HM seed oil were at an average concentration of 187.0 μg/g, which included α-tocopherol (21.4%), γ-tocopherol (78.2%), and δ-tocopherol (0.4%). The HM seed oil can be incorporated into food emulsions such as in DHA-enriched goat milk emulsion to stabilize added oil from oxidation. The HM seed oil was mixed with algae oil, a rich source of omega-3 docosahexaenoic acid (DHA; C22:6n-3), before emulsification and storage of goat milk. The addition of HM seed oil containing phenolics to algae oil at 1:1 ratio prior to goat milk emulsification significantly (p < 0.05) protected the goat milk emulsions against oxidative deterioration. In goat milk emulsions, the addition of ascorbyl palmitate retarded oxidation as was determined by the peroxide values and anisidine values.
Part of the book: Biochemistry and Health Benefits of Fatty Acids