With a health claim decision expected any day now by the Food & Drug Administration, and popularity growing worldwide, sales of omega-3 fatty acids such as EPA and DHA are booming, with no levelling in sight.
The challenge for formulators is getting omega-3 components into food sources without risking rancidity. Through the R&D efforts of corporations and academia, many of these formulation challenges are being overcome.
?Supplements with fish oils can give you the fish oil experience throughout the day whenever you burp,? noted Eric Decker, professor in the Department of Food Science at the University of Massachusetts. ?But food products don?t give you reflux problems.?
Rancidity, however, is the chief concern because even a small amount of oxidation affects flavour, said Decker.
The food matrix can be conducive or detrimental to fatty acid oxidation, according to Srinivasan Subramankin, ingredients developer at Martek Biosciences, which sources omega-3s from algae. It uses a proprietary and patented micro-encapsulation technology to deliver its omega-3s (mostly DHA) into soft gels and foods.
?Yoghurt, for example, is conducive because of lower temperatures for storage, a shorter shelf life, and because its strong acidic and sour flavour helps mask the polyunsaturated fatty acids,? he said.
Micro-encapsulation can protect omega-3s from secondary thermal processing, extend shelf life and prevent ingredient interaction. The most common mechanical micro-encapsulation technology is spray drying, said Subramankin, though fluid bed coating with spray drying and spinning disk are also sometimes used. Other broad technologies emerging include chemical and physicochemical means such as interfacial polymerisation and solvent evaporation.
Emulsification technologies are also used to stabilise omega-3s, said University of Massachusetts professor Julian McClements. They protect omega-3s by encapsulating them in emulsifications. Studies show mixed tocopherols are better than only alpha-tocopherol in slowing down the oxidation of omega-3s.
Transferring the oils to a powder form has also benefited oxidation. Ocean Nutrition is the leader in technology on this front. However, there is a caveat. Such powders tend to result in relatively lower amounts of EPA and DHA, according to Ian Newton, managing director of Ceres Consulting, based in Canada.
While contaminants such as mercury have caused concern in the consumer market for farmed fish, the same cannot be said of supplements. ?With proper refining there are no detectable levels of these contaminants in properly refined oils,? stated Robert Orr, president of Ocean Nutrition.
These technologies mean omega-3s are finding their way into diverse foods such as frozen foods, refrigerated foods from salad dressings to yoghurts, and baked goods like pizza dough.
To qualify for the health claim in the US, foods must contain a minimum of 125mg long-chain omega-3 fatty acids per serving, and be part of a food that is low in fat, saturated fat, trans fat and cholesterol.