August 13/Science Letter -- According to recent research from Lyngby, Denmark, "Fish oil (FO) enrichment of foods is relevant owing to the beneficial effects of omega-3 polyunsaturated fatty acids on human health. However, the susceptibility of FO to oxidation necessitates careful control to avoid this oxidation."
"In this study, energy bars were successfully supplemented with 5% FO. Heating of bars during baking did, apparently, not increase oxidation. Energy bars produced with neat FO were oxidatively unstable as measured by peroxide value, secondary volatile oxidation products and sensory analysis. Pre-emulsification of the FO with sodium caseinate in water offered similar protection toward oxidation as packaging the energy bars in modified atmosphere. These protection methods were although not as efficient as addition of FO as micro-encapsulated powder," wrote N.S. Nielsen and colleagues, Technical University of Denmark.
The researchers concluded, "Addition of the metal chelator ethylene diamine tetra-acetic acid (EDTA) (100-2000 ppm) to emulsified FO decreased the oxidative stability of the energy bars compared with the energy bars with emulsified FO but without EDTA."
Nielsen and colleagues published their study in International Journal of Food Science and Technology ("Methods for Reducing Lipid Oxidation in Fish-oil-enriched Energy Bars." International Journal of Food Science and Technology, 2009;44(8):1536-1546).
For additional information, contact N.S. Nielsen, Technical University of Denmark, Dept. of Seafood Research, National Institute Aquat Resources, DK-2800 Lyngby, Denmark.
From the August 17, 2009, Prepared Foods E-dition