Healthier Milk from Flax-Fed Cows?

By Robby Gardner, Associate Editor

Feeding flax (Linum usitatissimum) to cows can improve the nutritional quality of their milk, according to researchers from Oregon State University who fed various amounts of flax to 10 cows for two weeks.

The notion that a high-flax diet can boost a cow’s milk nutrients is nothing new. Previous studies consistently show this strategy yields milk that is higher in omega-3 alpha-linolenic acid (the omega-3 found in flax) and lower in saturated fat.

So what new information can we glean from Oregon State?

In assigning Holstein cows to a variety of flax levels-up to 7% (6 lb) of their daily diet-the researchers sought to uncover how much flax could be incorporated without negatively affecting the texture and structure of resulting milk products.

"We were looking for a sweet spot,” said lead scientist Gerd Bobe. “Too much of a good thing can be bad, especially when trying to maintain consistency with dairy products.”

The researchers formulated cow’s milk into whole milk, cheese, and butter products. When flax was incorporated into the diet, no negative effects were observed in resulting dairy products-regardless of the amount of flax added. A flax diet even resulted in butter that was less hard and less adhesive because of fewer saturated fats. Such qualities are reasonably believed to improve the spreadability of refrigerated butters.

As for nutritional results, a daily diet including 6 lb of flax resulted in whole milk that was 18% lower in saturated fat and 70% higher in omega-3s than whole milk from a cow fed zero flax. Similar improvements were found in butter and cheese. Because saturated fat still accounted for more than half of the fatty acids in dairy products, utilizing flax as an ingredient for healthy milk is all the more logical.

The flax-fed cows study is published in Journal of Dairy Science.