How to make infant formula from bovine milk

After my previous blog about the uniqueness of breast milk (link), it’s now time to dive into infant formula. There are many differences between breast milk and bovine milk. For example, the proteins, vitamin & minerals, lipids, and oligosaccharides all differ. For this reason, although bovine milk is the basis of infant formula, many changes need to be made to create infant formula.

For the proteins, the major difference is the lower protein level, especially of casein (the cheese protein), in breast milk, while it contains relatively high whey protein levels. So to make infant formula, whey protein is used as the basis, to make a product with lower protein content, with a concomitant shift from casein to whey protein.

One of the challenges of using whey as basis for infant formula, however, is that it contains much more minerals than breast milk. And for the infant kidneys, a lower mineral intake is important. Whey is therefore not used as-is, but after a step of mineral reduction, after which more pure whey protein is obtained. For other minerals and vitamins, several differences exist that are compensated by adding these as separate ingredients.

When it comes to lipids, more unsaturated fatty acids are present in breast milk. Therefore, plant oils are used, as these naturally contain more unsaturated fatty acids. Different plant oils, sometimes mixed with bovine milk fat, are used to reflect breast milk lipids best.

Finally, the oligosaccharide content is very different, with much higher contents in breast milk. In the past years, this was usually compensated by adding an oligosaccharide mixture (called GOS/FOS). Although this compensated the oligosaccharide level, GOS/FOS are different oligosaccharide structures. Recently, the production of a oligosaccharide structure that is also present in breast milk became possible.

This is however not the end. We still learn more-and-more each day about breast milk composition, its complexity and its beneficial effects. Challenges will thus remain to keep updating infant formula in future, to minimize these differences.

Kasper Hettinga, November 2017

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What is so special about breast milk?

I hope everyone is aware of the advice to breastfeed a baby in the first six months of life. In this blog, I’ll explain why breast milk is so special. What are the health benefits of breastfeeding? And which components in breast milk may be responsible for these benefits?

First, what are the benefits of breastfeeding? A recent literature overview by the Dutch Institute for Public Health and the Environment shows that even healthy babies in Western countries have short and long term benefits from drinking breast milk (link). There are many benefits, including for the mother. Most of the benefits for the infant are associated with the development of its immune system. So how does breastfeeding contribute to developing the infant’s immune system?

The first group of components that are important for developing a healthy immune system are immune-active proteins. Milk contains antibodies, anti-bacterial proteins, and immune-stimulatory proteins. On the one hand, this directly contributes to the defence against infections. On the other hand, these proteins also stimulate the immune system to mature, leading to a well-developed immune system for the infant.

Milk also contains complex sugar molecules that our body can’t digest, called oligosaccharides. These oligosaccharides are used by the good bacteria in the large intestine. The oligosaccharides in breast milk thereby lead to more of these good bacteria. This contributes to the immune system in two ways. First, if there are more good bacteria, it is more difficult for bacteria that may cause infections to cause problems. Second, these good bacteria, like proteins, can stimulate the immune system to mature.

Besides the proteins and oligosaccharides, milk contains many other components. For example, good bacteria that are transmitted alive to the infant, white blood cells, immune signalling components, and others. How much all these contribute to a healthy infant is not yet known. But it indicates that breast milk is a very complex liquid with many components that in synergy lead to a well-developed immune system, and thereby a healthy infant.

So what about bovine milk? The components mentioned above are only partly present in bovine milk and infant formula. But I will discuss bovine milk-based infant formula in more detail in a next blog post.

Kasper Hettinga, September 2017

Is drinking milk healthy?

One questions that is frequently asked to me, especially by journalists, is whether drinking milk is healthy. This often relates to a number of underlying questions; What are the benefits of drinking milk? What are the risks of drinking milk? Do we need to consume milk at all? In this blog, I will give my perspective on these questions.

First of all, what are the benefits of drinking milk? If we look at a Western diet, a relative large portion of minerals (calcium, magnesium, phosphorus, potassium and zinc) and B vitamins (B2, B11 and B12) originates from dairy products. A number of them (especially calcium, vitamins B2 and B12) hardly originate from other food sources in an average diet. On top of that, the protein in milk is easily digestible and provides a large share of our essential amino acid intake. Especially in a Western diet, rich in grains (bread, pasta, etc), milk provides those essential amino acids that are low in grain, making them a good complementary combination.

But what about the risks of drinking milk? There is a wide range of potentially harmful components in milk. Just try to google this topic and you may be afraid of drinking milk ever again. But are these allegations correct? I previously dealt with two topics, hormones and antibiotics in separate blog posts. In both cases, the risks of drinking milk are simply not there.

Finally, do we need to consume milk at all? Here, I believe the answer is “no, but…”. Although milk contributes many nutrients, as mentioned above, there are alternative sources for these nutrients. At the same time, one should realize that there is no single replacement that contains all these nutrients. Even plant based (e.g. soy) drinks do not provide the full nutritional quality of milk, especially when it comes to amino acid complementarity. So dairy would need to be replaced by a range of other foods. So although this is technically possible, I believe it is rather complicated and would change the diet more extensively.

So, is drinking milk healthy? In my opinion, the answer generally is yes. In our diet, it contributes many essential nutrients and leads to a well-balanced diet.

Kasper Hettinga, September 2017

What is the difference between fresh and long shelf life milk?

When buying milk in the supermarket, there is a wide choice. Two important types are fresh milk, that has a short shelf life and needs to be stored in the fridge, and long shelf life milk, that can be stored at room temperature. Different countries prefer different types of milk. Why does this difference exist? And does the type of milk make a difference to its quality and nutritional value?

The main difference between these types of milk is the temperature used during processing. For fresh milk, a mild pasteurisation is used, with temperatures around 72°C. This way, pathogenic bacteria are killed, making the product safe for consumption. Bacteria that can spoil the milk are however not killed, making it necessary to store the milk in the fridge. For long shelf life, ultra-high temperature (UHT) treatment is commonly applied, with very high temperatures (130-140°C) for seconds. This treatment kills all bacteria that may cause spoilage. This milk has a very long shelf life and can be stored at room temperature, because bacteria can no longer spoil the product. The advantage of UHT milk is that it does not require cooled transport/storage, making it easier for dairy companies & retailers to work with.

But why then do we not just sterilise all milk, if it makes life easier? This is mainly due to taste. Pasteurisation has only a very limited effect on taste compared to raw milk. UHT sterilisation, on the other hand, causes the formation of a specific flavour due to the high temperature used.

And what then about the nutritional value? The main nutrients in milk (protein, fat, lactose, minerals) are not harmed by UHT sterilization, keeping them intact. For some vitamins, small reductions (max 10%) can occur. So the nutritional quality is essentially the same. Only when sterilisation is more intense, which can be noticed through a brown colour, the nutritional value is lower, due to damage to the protein (essential amino acids).

I earlier wrote about raw milk (link) and the immunoprotective components in them. Those components are more harmed by UHT sterilisation than pasteurisation, although health benefits for consuming these components is currently very limited, especially in adults.

Summarizing, the main differentiation between fresh & UHT milk would be on taste and shelf life, whereas nutritionally these products are virtually identical.

Kasper Hettinga, August 2017

What type of milk does a toddler need, if any?

Breastfeeding is the best choice for feeding a baby and toddler, exclusive for the first 6 months and combined with other foods up to 2 years. However, the majority of children will not be breastfed that long, especially after the first year of life. Then, the question is what the best alternative would be. Breast milk provides high quality protein, calcium, and several B vitamins. These nutrients are also provided by regular milk. Therefore, 2 cups of milk (300 ml) are advised for young children. This milk provides these necessary nutrients to the developing child. Completely skipping milk from the diet is therefore unwise. Besides regular milk, there are several popular alternatives, toddler milk, goat milk, or plant-based alternatives.

A product that has gained interest in recent years is toddler milk, also called follow-up formula or growing up milk. This basically is milk enriched with several nutrients. Milk does not sufficiently provide several of these nutrients (e.g. iron, vitamin D, essential fatty acids). But as milk is not the only source of nutrients for toddlers, this is not a problem. A varied, healthy diet and separate vitamin D supplements should be sufficient to provide the necessary nutrients. So although toddler milk will provide many nutrients to the young child, this product is not necessary assuming a varied & healthy diet including regular milk.

Some children can not tolerate bovine milk, for example due to lactose intolerance or cow’s milk allergy. Parents may be tempted to try milk of other mammals. Especially goat milk is drawing a lot of interest recently. However, goat milk contains the same amount of lactose compared to bovine milk. Also when it comes to proteins, goat milk is very similar to bovine milk. Therefore, children with lactose intolerance can’t tolerate goat milk, as do the far majority of children with cow’s milk allergy. Goat milk is thus seldom a solution if bovine milk can’t be consumed.

Another group of alternatives for cow’s milk are plant based product like soy drink. In case of cow’s milk intolerance or allergy, soy drink can usually be consumed without problems. When choosing a soy product for a toddler, several aspects are important. First, the product should be enriched with the same nutrients as regular milk (calcium, B vitamins) because otherwise deficiencies may arise. Second, a product without added sugar is preferred to limit sugar intake. Even when choosing such a product, the protein quality of a soy drink will still be lower than of regular milk.

In conclusion, milk is an important source of nutrients in a toddler’s diet. Special toddler’s milk or goat milk have no apparent benefit over regular bovine milk. Plant based products like enriched, sugar-free soy drink can be a good alternative if bovine milk is not tolerated, although it’s not nutritionally identical.

Kasper Hettinga, April 2017

Is milk full of hormones?

After discussing the social media story on antibiotics earlier, I now want to move on to another component that is often thought to be present in milk at harmful levels: hormones.

First of all, milk does contain hormones. All animals (and humans, if you want to see that as a separate category) make hormones and they are present in all our tissues and secretions. So all our animal-derived food (and also breast milk) contains hormones. For milk, the interest is in two groups of hormones: growth hormones and sex hormones.

When it comes to growth hormones, it depends on where you live. In Europe there is a general ban on growth hormones (BST, IGF-1) in animal husbandry. Still, low levels due to natural presence of these hormones occurs in milk. In other parts of the world, they can be used in animal husbandry, leading to these hormones being present at higher levels in the milk as well.

When it comes to sex hormones, these occur in milk, because they are naturally secreted. In dairy animals, there levels fluctuate over lactation, especially due to most cows being pregnant during lactation. In late lactation, sex hormone levels are therefore somewhat higher.

What happens to these hormones during processing? Research shows that the hormones stay largely intact, except for BST that is broken down during regular dairy processing. There is no difference in hormone levels between regular and organic milk (assuming both did not inject hormones in their dairy animals). For comparison, breast milk contains 10-20 times higher levels of sex hormones than bovine milk.

After processing, we consume the milk. So does this cause any harm? If we look at growth hormones, BST is naturally broken down in our digestive tract. IGF-1 is not broken down, but levels in milk are lower than normally occurring levels of IGF-1 in our body. Sex hormones are also not broken down during digestion. But if we look at sex hormone intake through milk (and animal products in general), they are lower than our daily maximum intake, even at high consumption levels (liters per day). So, in conclusion, although milk (and animal products in general) contribute to dietary hormone intake, it is at such low levels that health effects are not to be expected.

Kasper Hettinga, December 2016

Is milk full of antibiotics?

Last week, there was European Antibiotics Awareness day. So, I took this opportunity to discuss the story that sometimes goes around on social media that milk is full of antibiotics nowadays.

So can there be antibiotics in milk? Yes, there can. If cows have an infection, they are treated with antibiotics, just like us humans. An important reasons that dairy cows get treated with antibiotics is an infection in the udder. The antibiotics used for this treatment can end up in the milk. The milk of cows treated with antibiotics should thus be collected separately and not go into the milk tank, to prevent contamination of the milk in the tank.

Because dairy processor want to be sure about the absence of antibiotics, every individual milk delivery is checked for the presence of antibiotics, before the milk is unloaded at the factory. If milk is found to be contaminated with antibiotics, the milk is destructed and the farmer get a financial penalty.

Besides human health, there is a second reason why dairy factories strictly control the absence of antibiotics, which is the effect it has on fermentation. Many dairy products (e.g. yoghurt and cheese) are made by fermentation, which is a process in which bacteria grow in the milk to achieve the specific taste & texture required. These bacteria used for fermentation do not grow if antibiotics are present. So that is an important reason to check every individual batch of milk delivered to the factory on the presence of antibiotics.

In conclusion, because every individual batch of milk is checked to confirm absence of antibiotics, milk is not a source of antibiotics in the human diet.

Kasper Hettinga, November 2016