As the health benefits of omega-3 fatty acids reach the awareness of consumers eager to improve the functions of their body -- from the cardiovascular system to the brain -- food makers are scurrying to enrich and fortify products with omega-3s and get them to market. But one major obstacle tempers progress -- flavor.
Great sources for omega-3s are fish oils, algal oils and linseed oil. Each can be highly susceptible to oxidation, however. That deteriorates flavor, increases the risk of rancidity and reduces shelf-life.
"Many food companies still don't believe that fish oils can be put in food and that it can still taste good, but there are methods," said Ian Newton of Ceres Consulting in Canada.
Proper handling techniques and special fortification can remedy these hurdles in many cases, and research is moving forward to find more flavorful fortification techniques.
Speaking last Wednesday at the Institute of Food Technologists Annual Meeting and Food Expo, the world's largest annual food science and ingredient convention, scientists described one problem in omega-3 fortification is the compounds that serve as efficient antioxidants can, conversely, increase oxidation in complex food systems.
In a case study of omega-3 fatty acids in mayonnaise, researchers with the Danish Institute for Fisheries Research found that the dressing's low pH, combined with high iron content -- caused by egg yolks in mayonnaise -- are main factors that cause lipid oxidation. They suggested that flavor could perhaps be improved with lower iron levels.
Studies by the same team on the flavor quality of milk that had been fortified showed that flavor improved dramatically when rapeseed oil was used as the source of omega 3s.
Copper can be as big a problem as iron in causing oxidation. Newton described a case of omega-3 enriched margarine makers who experienced an increase in the fishy flavor of their product while at the same time its shelf-life decreased.
"Finally, they realized it started when they changed sea salt suppliers. The new sea salt. . .contained just a small level of copper that triggered a large amount of oxidation," he said.
Foods that contain any levels of peroxide will also have oxidation problems, said the researchers.
Retaining the flavor and shelf life of omega-3 fortified foods can be a simple matter of carefully handling products and thoughtful placement of oils in the ingredient stream, said Brian Langdon, of Omega Protein Inc.
Adding omega-3s as close to the end of the ingredient stream as possible is helpful, he reported, with the best time to add is before the final mixing of the product.
According to the panelists, some products that are emerging as the best for omega-3 fortification include frozen food entrees, soups, refrigerated foods, salad dressings, yogurts, spreads, juices, egg products and cheeses, which are especially helpful in providing omega-3s due to their attraction to a wide audience, ranging from children to the elderly.