UK – Cows that are fed on a diet containing certain levels of rapeseed oil produce milk with noticeably lower levels of saturated fat, according to research conducted at Queen’s University Belfast.

Rapeseed is rich in unsaturated fats, which pass through the cow’s digestive system and into the milk. Cows that eat 600g of the oil a day produce milk with 35% more oleic acid – a naturally occurring unsaturated fat in rapeseed – and 26% less palmitic acid, a saturated fat linked to heart disease and obesity.

The results were published in the Journal of the Science of Food and Agriculture, and give credence to Naturally Spreadable Butter, which is made from cows fed higher levels of rapeseed oil and is available at Marks & Spencer stores.

The rapeseed oil also changes the milk’s fat composition so that when butter is produced from it, it is more spreadable.