Irish grass-fed milk contains more beneficial nutrients than milk from conventional indoor-feeding practices, according to research from Teagasc and Food for Health Ireland (FHI).

The study compares the Irish grass-fed system to what is more commonly operated around the world, whereby cows are housed indoors year round to maximise the quantities of milk produced. 

Irish grass-fed dairy cows produced milk with higher percentages of omega-3 and conjugated linoleic (CLA) fatty acids, than cows fed medium and low proportions of grass.

While grass-based feeding systems are the “most common” source of dairy produce in Ireland, PhD researcher at the Teagasc Food Research Centre, Moorepark, Co. Cork, Mark Timlin said:

“The levels of fresh grass fed to dairy cows in countries such as the United States, Germany, Austria and Denmark is significantly less than in Ireland.”

The research conducted compared the impact of three dairy systems on the nutritional composition and properties of milk.

These systems included:

  • A high-grass allowance diet, typical of that operated by Irish farmers;
  • A medium-grass allowance diet; and
  • A low-grass allowance diet most commonly operated around the world.

The scientific paper titled Impact of varying levels of pasture allowance on the nutritional quality and functionality of milk throughout lactation was published in the Journal of Dairy Science.

Irish grass-fed system

Researchers found that cows which grazed on an Irish high-grass allowance diet produced milk with significantly more beneficial nutrients, compared to cows fed a medium, or low-grass diet.

These findings include:

  • 83% increase in omega-3 fatty acids, including an improved n-3 to n-6 ratio;
  • 141% increase in conjugated linoleic acids (CLA);
  • Highest levels of unsaturated fatty acids (including mono- and polyunsaturated);
  • Lowest levels of saturated fatty acids.

The high-grass allowance diet is typical of the system implemented by most Irish dairy farmers, and meets the Bord Bia grass-fed standard, Teagasc lead scientist, Dr. André Brodkorb said.

The results are part of wider research which studies the composition, functionality and sensory characteristics of Irish grass-fed dairy and the impact of the cow’s diet on human health.

This is according to FHI centre director, Dr. Nessa Noronha. Commenting that this study gives consumers in Ireland and abroad a “reason” to buy a premium Irish product, she said:

“On a global scale, a premium may now be applied to Irish grass-fed dairy products, highlighting the nutritional benefits of ensuring a more natural and sustainable way of life for the farms in Ireland.”

Previous research has shown that pasture-based, grass-fed systems are seen as more natural and better for the environment, allowing cows to express their natural behaviours by grazing, Teagasc said.