Feed cows with flax seed to get more nutritious dairy products

Feed  cows with  flax seed to get more nutritious dairy products

When I was young,  I liked to drink plenty of milk.  As a matter of fact, I liked all dairy products. I have heard our grandmother saying that the taste of milk depends on the food  cow eats regularly. I did not believe it.

She knew it from closely watching our cows. Since our cows were not allowed to  graze in the fields most of what they consume was stored  cattle feeds such as oil cakes and agricultural and food wastes. Our grandmother claimed that if we feed cows with the wastes from jackfruit, milk tastes differently compared to straw or grass.  Herbs gave a special flavor .

 OSU researcher Gerd Bobe led a study that fed flaxseed to dairy cows and examined the effects to milk, cheese and butter. (Photo by Hannah O'Leary.)

These observations were simply not grandma tales. Not anymore! Researchers at the Oregon State University has shown that dairy cows that are fed flaxseed produce more nutritious milk.

Their milk contained more omega-3 fatty acids and less saturated fat, the study found.

Diets high in saturated fat can increase cholesterol and cause heart disease, while those rich in omega-3 and other polyunsaturated fatty acids may reduce the risk of heart disease, studies have shown.

Traditional cattle feed mixtures of corn, grains, alfalfa hay and grass silage result in dairy products with low concentrations of omega-3 and other polyunsaturated fats, according to Gerd Bobe, the lead scientist on the study, which has been published online in the Journal of Dairy Science.

Researchers fed ten pregnant cows at OSU's dairy different amounts of flaxseed – up to seven percent of their daily diet. They attempted to pinpoint the amount of flaxseed that would maximize the amount of omega-3 in milk and dairy products without negatively affecting their production and texture.

 One of the special requirements of food industry is that the products must maintain consistency. Otherwise, consumers will find it unacceptable. Researchers carried out detailed studies to get the right mix of flax seeds in cattle feed

Collaborators in OSU's food science and technology department assisted in turning milk into butter and fresh cheese, which were then tested for texture and nutritional composition.

Researchers found  that feeding cows up to six pounds of extruded flaxseed improved the fat profile without negatively affecting the production and texture of the milk and other dairy products. Extrusion presses raw ground flaxseed into pellets with heat.

At six pounds per day, saturated fatty acids in whole milk fat dropped 18 percent, poly-unsaturated fatty acids increased 82 percent, and omega-3 levels rose 70 percent compared to feeding no flaxseed.

Similar improvements were observed in butter and cheese.

Still, saturated fat accounted for more than half of the fatty acids in the dairy products while the increase in polyunsaturated fats comprised no more than nearly nine percent of the total.

Researchers noted that the refrigerated butter was softer and less adhesive thanks to the presence of fewer saturated fatty acids. Also, the cows produced the same amount of milk while eating flaxseed.

Although flaxseed costs more than traditional cattle feeds, Bobe hopes that it still could be an affordable feed supplement for cows because products enriched with omega-3 can sell for a premium at the grocery store.

"Many consumers already show a willingness to pay extra for value-added foods, like omega-3 enriched milk," he said. Fortunately cows loved eating flax seeds like candy.