From a chemical point of view, milk is one of the most complex fluids in the world. It is a heterogeneous mixture made up of different components in unstable equilibrium. This characteristic is also reflected in the differences between various types of milk, like, for example, sheep milk and cow’s milk.
When comparing the composition of sheep milk and cow’s milk, there are major differences as far as nutrients are concerned. To be specific, sheep milk contains less water than cow’s milk (82% compared to 87.5%) but more fat (6.5% compared to 3.6%). This is reversed however with regard to cholesterol; sheep milk has a lower concentration of cholesterol (11mg/100g) than standard cow’s milk (14mg/100g).
Sheep milk also contains a higher percentage of protein (5.5% compared to 3.2%). The percentage of lactose, however, is the same (4.8% for sheep milk and 4.7% for cow’s milk). The percentage of minerals is also almost identical although sheep milk contains slightly more (0.92% compared to 0.72% in cow’s milk). The amounts of calcium and phosphorus, the two main minerals in milk and one of the main reasons why it is consumed, vary considerably however. 100g of sheep milk contains 193mg of calcium compared to the 119mg in cow’s milk, and 145mg of phosphorus compared to the 93mg in cow’s milk.
As far as vitamins are concerned, milk contains Thiamin (B1), Riboflavin (B2) and Niacin (B3), as well as fat-soluble vitamins such as A and E. Also here sheep milk is generally a lot more nutritious than cow’s milk with regard to the following: Riboflavin (230/382mg/100g compared to 162/215mg/100g), Vitamin C (4000/5000mg/100g compared to 940/2400mg/100g), Niacin (400/450mg/100g compared to 84/270mg/100g) and Pantothenic Acid (450mg/100g compared to 314mg/100g). A part of the vitamins to be found in sheep milk come from Rumen bacteria.
As far as fatty acids are concerned, both types of milk contain Conjugated Linoleic Acid (CLA) which is potentially considerably beneficial to human health. On average, sheep milk contains more than cow’s milk (4/10mg/g compared to 2/11mg/g).