Flaxseed-fed cows produce omega-3-rich milk, US researchers claim

Lactating cows fed flaxseed produce milk containing more omega-3 fatty acids and less saturated fat, US researchers have claimed.

A study conducted at Oregon State University (OSU) has found that cows fed up to 2.72kg of extruded flaxseed produced milk with an improved nutritional profile, and without negatively impacted texture or production parameters.

At 2.72kg per day, saturated fatty acids in whole milk fat dropped by 18%, poly-unsaturated fatty acids increased 82%, and omega-3 levels increased 70%.

This milk was then manufactured into butter and fresh Mozzarella cheese. Similar nutritional improvements were observed in the butter and cheese produced.

More fatty acid, less saturated fat

According to the study, Effect of flaxseed supplementation rate and processing on the production, fatty acid profile, and texture of milk, butter and cheese, extruded flaxseed is high in fatty acid C18:3n-3.

Diets high in saturated fat can lead to increased cholesterol and cause heart disease, while those rich in fatty acids such as oemga-3 may reduce the risk of heart disease.

“Health and nutrition professionals advise consumers to limit consumption of saturated fatty acids and increase the consumption of foods rich in n-3 fatty acids,” said the report.

“Researchers have previously reported that feeding extruded flaxseed, which is high in C18:3n-3, improves the fatty acid profile of milk and dairy products to less saturated fatty acids and to more C18:3n-3.”

“The objective of this study was to determine the optimal rate of flaxseed supplementation for improving the fatty acid profile without decreasing production characteristics of milk and dairy products,” said the report.

Without negatively affecting texture

Under the study, ten pregnant cows were fed different amounts of flaxseed. Researchers then attempted to pinpoint the amount of flaxseed needed to maximise the amount of omega-3 in the milk and dairy products without negatively affecting production parameters or texture.

“Increasing supplementation rates of extruded flaxseed improved the fatty acid profile of milk butter, and cheese gradually to less saturated and atherogenic fatty acids and to more C18:3n-3 by increasing concentrations of C18:3n-3 in serum,” the report added.

“Flaxseed processing did not affect production, fatty acid profile of milk, or texture of butter and cheese. Feeding up to 2.72kg per day of extruded flaxseed to mid- to late-lactation Holstein cows may improve nutritional and functional properties of milk fat without compromising production parameters.”