Antioxidant Protection of an Omega-3 Fatty Acid Fortified Dairy-Based Beverage

Abstract

Skim, butter-derived aqueous phase, anhydrous milk fat, and fish oil were used to formulate ultra high temperature (UHT) processed extended shelf-life omega-3 fatty acid fortified dairy-based beverages with fat contents mimicking whole milk (3.25%). Oxidation of the lipids in the formulated beverages was investigated during storage for 35 days at 4 °C using GC/MS analysis, conjugated diene analysis, and headspace solid phase micro-extraction GC/MS (SPME-GC/MS) analysis of headspace. Omega-3 fatty acid fortified dairy-based beverages were produced that mimicked the physical properties of 3.25% fat whole milk. Oxidation resulted in only small changes in omega-3 lipid content and sensory analysis by an untrained panel indicated that the overall aroma was no different than that of commercially available UHT processed milk. An omega-3 fatty acid fortified dairy-based beverage was produced that delivered 440mg of omega-3 fatty acid per 8oz serving. When consumed daily, the beverage could provide the equivalent amount of omega-3 fatty acids recommended by the American Heart Association, and the equivalent amount of omega-3 fatty acids found in two fatty fish meals over the period of one week.<p> Antioxidants were added to the lipid phase, immediately prior to processing, of additionally produced formulations to determine if a reduction in omega-3 lipid oxidation was observed. No overall reduction in oxidation was observed, as indicated by GC/MS and SPME-GC/MS analysis. Sensory analysis indicated that oxidative aromas increased during storage for the antioxidant and omega-3 fatty acid fortified dairy-based beverage. Ascorbyl palmitate was determined to have a pro-oxidative effect on the formulated omega-3 fortified dairy-based beverages. Antioxidants present in the commercial grade fish oil used for fortification were effective in controlling oxidation in the formulated omega-3 fatty acid fortified dairy-based beverages.