Researchers at Virginia Tech say milk is an overlooked delivery vehicle for omega-3 fatty acids, which increasingly are viewed as beneficial to health.
The main omega-3 source in the diet is fish but researchers say incorporating omega-3 into milk and dairy-based beverages is a way to increase its consumption. They say it can be added to milk in amounts sufficient to promote heart health without destroying the product's taste or limiting its shelf life.
And best of all, it reportedly passes the smell test. Twenty-five volunteers evaluated one-ounce cups of standard 2 percent milk alongside samples of skim milk containing 78 parts butter oil to 22 parts fish oil in institutionally approved study conditions.
"We couldn't find any aroma differences," said Susan E. Duncan, a professor of food science and technology in the College of Agriculture and Life Sciences. "We were concerned the fish oil would undergo a chemical process called oxidation, which would shorten the milk's shelf life, or the milk would acquire a cardboard or paint flavor by reacting with the fish oil. It appears we have a product that is stable, with no chemical taste or smell issues."
The aroma-free fortified milk delivered 432 milligrams of heart-healthy fatty acids per cup, close to the 500 milligram daily target for healthy people suggested by a broad range of health studies. The U.S. Department of Agriculture suggests daily consumption of 250 milligrams per day in healthy adults.
This is significant since recent research has shown omega-3 fatty acids are helpful for preventing coronary disease, reducing inflammation, and providing other health benefits.
The American Heart Association recommends eating two servings of fatty fish per week, citing research that has shown omega-3 fatty acids decrease the risk of potentially fatal heart arrhythmias, decrease triglyceride levels, slow growth of atherosclerotic plaque, and slightly lower blood pressure.
But not everyone eats fish. That, says researchers, means there is a need for new foods and beverages fortified with omega-3s in the marketplace. Sales are expected to reach more than $3 billion in 2016, according to marketing analysts.
"I think the dairy industry can look at our study and determine whether it is plausible to modify its products," Duncan said. "I would like to help people who love milk, yogurt, and dairy, which have intrinsic nutritional value, address an additional need in their diets, especially if they don't like to eat fish or can't afford it. One of these dairy servings a day apparently is enough to sustain enough continuous omega-3 to benefit heart health."
If such a product catches on with consumers, Duncan said the next step for researchers is to follow groups of volunteers in a study to determine whether the food improves health. And milk has a history of being used to deliver other healthy substances.
"Milk was first fortified with Vitamin D as a way to fight rickets -- a disease that leads to soft or weak bones," said Kerry E. Kaylegian, a dairy foods research and extension associate with Penn State's College of Agricultural Sciences, who was not involved in the research. "It was a good approach to address a dietary deficiency disease, because so many people drink milk, which is already loaded with nutrients. This study describes fortification of milk with omega-3 fatty acids EPA and DHA. We can't say lack of those compounds definitively causes cardiac disease, but there is evidence that they protect us and contribute to heart and brain health. Milk would be a good delivery vehicle for those nutrients."