Healthier milk straight from the cow

British scientists have found a natural way to produce healthier milk and butter, according to new research in the Journal of the Science of Food and Agriculture. Cows fed rapeseed oil as part of their daily diet produce milk with a significantly less saturated fat. Butter made from the milk is easier to spread at fridge temperatures because it is lower in saturated fat than ordinary butter. According to Anna Fearon, one of the authors of the study: “This kind of tailored milk production could in future be applied to make any dairy product healthier, from cheese to ice cream”.

High in good fat, low in bad fat

Increasing the amount of rapeseed oil in the cows’ diet had an effect on the kind of fats their milk contained – unsaturated fatty acids (the ‘good’ fats) went up while saturated fatty acids (the ‘bad’ fats) went down. Cows eating 600g of oil a day produced milk with 35% more oleic acid, the unsaturated fat that is also present in olive oil, than cows on an ordinary diet., and 26% less palmitic acid, the saturated fat which has been linked to heart disease and obesity.

Future tests

Fearon and her colleagues tested the effect of four different amounts of rapeseed oil – the control group got none, while other parts of the herd were given 200g, 400g or 600g a day. The cows’ milk got ‘healthier’ with each increase of oil in their diet, and the cows themselves also stayed healthy. “The milk fat changes showed no signs of plateauing-out as the amount of dietary rapeseed increased,” the authors point out. “it seems likely that by giving dairy cows even more oil supplement in their diet, we can achieve an even more beneficial balance of fatty acids.”