The Composition of Breast Milk

Next, I’m gonna talk about the composition of breast milk What are the differences between breast milk and baby formula? First, let me explain how does the baby formula manufactured. We can find baby formula from cow milk or goat milk. Whether the baby formula comes from cow milk or goat milk, the main ingredients of formula milk comes from a mammal’s milk. Based on the needs of the babies, formula milk will then be further adjusted to a more appropriate composition. This is the biggest difference. So what are the components difference between human breast milk and other mammals milk? You can look from this slide. Breast milk, cow milk, and goat milk. You can see the differences and comparisons of these three milk.

Breast milk has more lactose in it Comparing to cow milk and goat milk, breastmilk has a lower content of protein while animal milk contains more protein in it. Why is breast milk contain less protein? The protein contained in the milk of mammals is related to the speed of growth and development. This chart shows how many days each animal and human needed to grow twice the amount of their birth weight. Obviously that the human babies requires the longest time Babies require 180 days for them to increase twice of their birth weight Different from other animals, like rats only needed 6 days or cows that needed 47 days.

Human babies need 6 months of time in order to gain twice their birth weight. Therefore, it is normal that the protein content in breast milk is much lower. Other than the differences of three nutrients, the main components of protein is also different. From this image, we can see that the casein content in breast milk is much lower, But the casein in the milk, the element to produce cheese, has a much higher percentage in cow milk. Among them, the ratio in the breast milk is 40% casein and 60% whey protein. However, cow milk is with 80% casein and only 20% whey protein. So when manufacturing baby formula, we probably will think to add more whey protein.

But the whey protein from cow milk contains allergens that might cause allergy to human babies Once the ratio of whey protein is increased, it might also cause higher chance for babies’ allergy reaction. That is to say, the protein content in the breast milk is much appropriate for human babies. Other than different protein, the content and composition of fat are also different. This image on left shows the fat composition of breast milk. Other than fat, it also contain lipase and essential fatty acids But the cow milk doesn’t have any of them. This is usually why baby formula uses skimmed milk powder, and adding vegetable oils to produce the baby formula suitable for human babies Why we’d use vegetable oils?

It is because vegetable oils are essential long chain fatty acids and these long-chain fatty acids are the ones that we need. Generally, the fatty acids from cow milk are saturated short-chain fatty acids.