Effects of Green Tea Extract and α-Tocopherol on the Lipid Oxidation Rate of Omega-3 Oils, Incorporated into Table Spreads, Prepared using Multiple Emulsion Technology
Article first published online: 21 NOV 2012
© 2012 Institute of Food Technologists®
Journal of Food Science
Volume 77, Issue 12, pages N58–N65, December 2012
How to Cite
Dwyer, S. P.O’., O’Beirne, D., Ní Eidhin, D. and O’Kennedy, B. T. (2012), Effects of Green Tea Extract and α-Tocopherol on the Lipid Oxidation Rate of Omega-3 Oils, Incorporated into Table Spreads, Prepared using Multiple Emulsion Technology. Journal of Food Science, 77: N58–N65. doi: 10.1111/j.1750-3841.2012.02980.x
- Issue published online: 13 DEC 2012
- Article first published online: 21 NOV 2012
- MS 20120868 Submitted 6/26/2012, Accepted 9/7/2012.
- double emulsion;
- lipid oxidation;
- omega-3 oil;
- table spread
Abstract: This study examined the effectiveness of fat and water soluble antioxidants on the oxidative stability of omega (ω)-3 rich table spreads, produced using novel multiple emulsion technology. Table spreads were produced by dispersing an oil-in-water (O/W) emulsion (500 g/kg 85 camelina/15 fish oil blend) in a hardstock/rapeseed oil blend, using sodium caseinate and polyglycerol polyricinoleate as emulsifiers. The O/W and oil-in-water-in-oil (O/W/O) emulsions contained either a water soluble antioxidant (green tea extract [GTE]), an oil soluble antioxidant (α-Tocopherol), or both. Spreads containing α-Tocopherol had the highest lipid hydroperoxide values, whereas spreads containing GTE had the lowest (P < 0.05), during storage at 5 °C, while p-Anisidine values did not differ significantly. Particle size was generally unaffected by antioxidant type (P < 0.05). Double emulsion (O/W/O) structures were clearly seen in confocal images of the spreads. By the end of storage, none of the spreads had significantly different G′ values. Firmness (Newtons) of all spreads generally increased during storage (P < 0.05).
Practical Application: Lipid oxidation is a major problem in omega-3 rich oils, and can cause off-odors and off-flavors. Double emulsion technology was used to produce omega-3 enriched spreads (O/W/O emulsions), wherein the omega-3 oil was incorporated into the inner oil phase, to protect it from lipid oxidation. Antioxidants were added to further protect the spreads by reducing lipid oxidation. Spreads produced had good oxidative stability and possessed functional (omega-3 addition) properties.