The Milk Series - Part 1 - Dairy

Hi I’m Sammy, 

Your Good Farm in-house nutritionist. Here to bring you essential information on nutrition, diet and permaculture gardening - in a bite size, easy to understand, science-backed way.

The Milk Series

Part 1 - Dairy milk

Gone are the days when you asked for milk and simply got milk. Now the choices are seemingly endless: full cream, skim, A2, lactose-free, organic and non-homogenised. There is so much to unpack that this milk series comes in two parts: dairy milks and non-dairy milks. But, of course, let’s start at the very beginning with traditional dairy.

Dairy milk today can look very different from what our grandparents and great-grandparents drank. Milk once arrived fresh on the doorstep in glass bottles, often from nearby farms, with a thick layer of cream sitting on top. While dairy is not essential for good health, it can provide valuable nutrients for those who tolerate it, including high-quality protein, calcium, phosphorus, vitamin B12 and iodine. But the quality of that milk, and how it is produced, can vary considerably.

So, what has changed?

From paddock to supermarket shelf

Today, a bottle of supermarket milk may contain milk from many different farms and breeds of cows. It can travel long distances, including across state borders, before being pooled at a processing facility.

Once there, the milk is tested, blended and standardised to create a consistent fat content. This can involve separating the cream and adjusting how much is returned before the milk is homogenised, pasteurised, cooled and bottled. Some milk undergoes additional processing to create lactose-free, flavoured or long-life products.

The result is a product that looks and tastes much the same year-round. What becomes harder to see is where that milk came from, what the cows were eating, how the farm was managed and how the milk naturally changed with the seasons.

A cow’s diet and environment

Just as the quality of soil shapes the food grown in it, a cow’s diet shapes the milk she produces. Milk from pasture-fed cows often has a richer flavour, more golden cream and higher levels of omega-3 fats, conjugated linoleic acid and beta-carotene. Full-fat milk retains more of these beneficial fats and fat-soluble nutrients than reduced-fat varieties.

What happens in the paddock also shapes the environmental footprint of that milk. Well-managed grazing can support healthier soil, greater plant diversity and improved water retention, while manure returns nutrients to the land. Regenerative dairy farms may rotate cows between paddocks, allowing pastures time to recover and reducing reliance on synthetic fertilisers.

As dietitian and sustainability advocate Diana Rodgers puts it: “It’s not the cow, it’s the how.” A sustainable diet is not simply about avoiding animal products but understanding how our food is produced, both animals and plants, and whether those farming practices support or deplete the land.

Pasteurisation vs Raw Milk

Pasteurisation uses controlled heat to reduce disease-causing microorganisms. It was one of the most important food-safety developments in the history of milk, particularly before reliable refrigeration and modern hygiene.

It does, however, change milk. Heating affects some bacteria, enzymes, immune compounds and heat-sensitive vitamins, although research suggests ordinary pasteurisation has only a small overall effect on its major nutrients. Protein, fat, calcium and most of the nutrients for which we drink milk remain largely intact.

Anecdotally, some people say they tolerate raw milk better than pasteurised milk. This may relate to differences in the milk, the herd, freshness, fat content or processing, but the research is not yet strong enough to say that raw milk is generally easier to digest.

Pasteurisation is not one single process. Larger commercial dairies typically use higher temperatures for shorter periods, while smaller dairies may choose gentler, lower-temperature batch processing to preserve more of the milk’s natural character. Ultra-high-temperature (UHT) milk undergoes more intense heating to make it shelf-stable.

This brings us to raw milk. The traditional view sees raw milk not as supermarket milk with one processing step removed, but as a fresh food from healthy, pasture-raised animals, produced and consumed close to its source.

I listened to a podcast with farmer and food writer Matthew Evans, who offered a useful way of thinking about it. Raw milk belongs to a different food system. It must be chilled quickly, handled carefully and consumed very fresh. If it were legally available, Evans argues, it should come directly from farms operating under strict testing and handling requirements. You would want to know where it came from, when the cows were milked and how the milk had been stored.

Pasteurisation and refrigeration allowed milk to travel farther, last longer and become a large-scale commodity. Raw milk belongs to a smaller model built around proximity, freshness, traceability and trust. It cannot just be placed into the industrial supply chain with the pasteurisation step removed.

Much of our food system prioritises shelf life and transportability. These things have made food more accessible, but convenience and longevity are not always the same as quality. When nutrient density is our goal, as I repeat time and again, we are often led closer to the source, asking how the food was raised, when it was produced and what happened before it reached us.

Raw cow’s milk cannot legally be sold for drinking in Australia, although some other countries permit it under regulated schemes.

Homogenisation

Milk naturally separates. Given time, its larger fat globules rise and form a layer of cream at the top. Homogenisation was introduced to stop this happening and create the smooth, uniform milk most of us grew up buying from the supermarket.

To homogenise milk, it is forced at high pressure through a very small opening. This breaks the naturally larger fat globules into tiny droplets. Their original membranes are disrupted and the droplets become coated with other milk proteins, preventing them from joining together and rising again. Nothing is necessarily added or removed, but the physical structure of the milk is changed.

From a traditional-food perspective, that extra step is worth questioning. The membrane surrounding each natural fat globule contains phospholipids and other bioactive compounds that researchers are still learning about. Homogenisation changes this structure and the way the fat is digested, although current evidence has not established that it damages the gut, prevents nutrient absorption or causes disease.

For me, choosing non-homogenised milk is about choosing a product that is one step less processed and closer to the form in which it left the cow. I enjoy its richer texture, I like seeing the cream line, and it usually points towards a smaller producer making full-cream milk with less intervention.

Give the bottle a gentle shake if you want to mix the cream back through or claim the cream from the top for yourself.

Lactose intolerance

Lactose intolerance occurs when the small intestine does not produce enough lactase, the enzyme needed to digest lactose, the natural sugar in milk. Most babies produce plenty of lactase, but levels decline after childhood in much of the world.

In populations with a long history of dairying, however, humans evolved the ability to continue producing lactase into adulthood. So, the idea that humans are simply “not meant” to drink cow’s milk misses’ part of the story. Some of us have adapted to digest it, while others have not. Tolerance varies partly according to genetics and ancestry.

Lactose intolerance can also be temporary, particularly after an infection or another condition damages the lining of the small intestine. Some people need lactose-free milk, while others tolerate small amounts, yoghurt or hard cheese. Persistent digestive symptoms should be properly investigated rather than automatically blamed on dairy.

What is A2 milk?

A1 and A2 are variants of beta-casein, a protein found in cow’s milk. A2 is the older form and is more common in heritage breeds such as Jersey and Guernsey cows, although breed alone does not guarantee A2 milk.

Some people find A2 milk easier to digest, but it still contains lactose and other milk proteins, making it unsuitable for those with a milk allergy. Fermented dairy, such as yoghurt and aged cheese, may also be better tolerated.

An important note on allergy versus intolerance

A cow's-milk allergy is an immune reaction to one or more milk proteins. Reactions can include hives, swelling, vomiting, wheezing, blood in the stool or, rarely, anaphylaxis.

An intolerance does not involve the same allergic mechanism. Lactose intolerance occurs when there is not enough lactase enzyme in the small intestine to digest lactose, the natural carbohydrate in milk. Symptoms may include bloating, wind, pain and diarrhoea. Lactase production varies between people and populations, and temporary lactose intolerance can occur after gastroenteritis or injury to the intestinal lining.

Lactose-free cow's milk has lactase added to break the lactose into simpler sugars. It still contains cow's-milk protein. Fermented dairy such as yoghurt and kefir may be better tolerated by some people because cultures digest some of the lactose, but the amount remaining varies between products.

Full fat over skim

It is time to ditch skim and “lite” milk and bring back the fat. For decades, we were told that removing dairy fat would make milk healthier, yet emerging research has associated full-fat dairy with neutral, and in some studies more favourable, cardiometabolic outcomes than we were once led to believe.

Skim milk began as the liquid left after valuable cream was separated for butter-making. Before it was transformed into a diet product, much of it was discarded or fed to farm animals; food historian Kendra Smith-Howard notes that it was once referred to as “hog slop.” We then found a way to package and market what had previously been treated as a low-value by-product.

To produce skim milk, whole milk must be separated and standardised, removing almost all its naturally occurring fat along with fat-associated compounds that contribute flavour, texture and satisfaction. Plain skim milk does not usually contain added sugar, but it can contain slightly more naturally occurring lactose per 100 millilitres because the fat has been removed and the remaining milk components become proportionally more concentrated.

If you tolerate dairy and have no medical reason to restrict it, choose the milk closest to the whole food, with all the flavour of its natural fat intact. Nom!

Fermented milk

Cultures around the world developed their own ways of fermenting milk, from yoghurt and cultured buttermilk to Indian lassi and Scandinavian filmjölk. Kefir is traditionally associated with the Caucasus Mountains, where communities used living “grains” of bacteria and yeasts to ferment milk and passed them down through generations. These microbes transform some of the lactose, create acids and other compounds, and produce a tangy drink that many people find easier to tolerate than fresh milk. When it has not been heat-treated afterwards, kefir also provides a diverse community of live microorganisms alongside protein, calcium, phosphorus and B vitamins, although its exact benefits vary with the grains, milk and fermentation method.

What I look for when buying milk

When I visit family on the Mid North Coast, we stock up on milk from Hastings Riverlands Dairy. Fifth-generation farmer Jimmy Eggert produces single-source milk from his Jersey herd, processes and bottles it on the farm, and uses lower-temperature batch pasteurisation rather than high-temperature continuous processing. It is also non-homogenised and produced using organic farming practices. The colour, texture and flavour are next level. Dream milk!

When I am shopping at a supermarket or local grocer, I look for certified organic, full-cream milk that is non-homogenised and, where possible, single source. It will not always tick every box, but these labels help me find milk that is a little less processed and easier to trace back to where it came from.

Oli’s mango, turmeric and kefir lassi

This much-loved drink makes a regular appearance in our household as the weather warms up. It is a great way to introduce kefir to kids, or adults, who are not used to drinking it straight, and its combination of protein, fats and carbohydrates makes it a well-balanced snack.

·      1 cup organic frozen mango

·      1 cup plain, full-fat kefir

·      ¼ cup full-fat milk, or more if needed

·      ¼ teaspoon ground turmeric

·      A pinch of ground cardamom

·      Optional: 1 scoop unflavoured collagen powder

·      Optional: a little honey or a squeeze of lime

Blend until smooth and creamy, adding extra milk, mango or honey as needed. Taste and adjust as you go. My ratios change every time and are never exact.

If you do not have kefir on hand, use full-fat milk and full-fat yoghurt instead.

Keeping with the milky goodness theme, three of our family’s favourite milk-rich meals are the Mac ’n’ Cheese and Cauliflower Cheese, and Stroganoff, all made with organic milk/cream and plenty of flavour.

Up next: Part Two, Non-Dairy Milks. Are they really the healthier and more sustainable choice?

Further exploring

Sacred Cow, documentary by Diana Rodgers and Robb Wolf. Explores the relationship between animal agriculture, nutrition and regenerative farming.

Milk: The Truth, the Lies and the Unbelievable Story of the Original Superfood, by Matthew Evans. An investigation into the history, science and politics of milk.

Soil: The Incredible Story of What Keeps the Earth, and Us, Healthy, by Matthew Evans. Explores the connection between soil health, farming practices and the food we eat.

Nutrition and Physical Degeneration, by Weston A. Price. Examines traditional diets and the role of nutrient-dense foods, including dairy, in human health.

References

Food Standards Australia New Zealand. Raw Drinking Milk.

NSW Food Authority. Dairy Food Safety Scheme: Guidelines for Small Dairy Processors.

Macdonald, L.E. et al. “A Systematic Review and Meta-analysis of the Effects of Pasteurisation on Milk Vitamins.” Journal of Food Protection, 2011.

Michalski, M.C. “On the Supposed Influence of Milk Homogenisation on the Risk of Cardiovascular Disease, Diabetes and Allergy.” British Journal of Nutrition, 2007.

Alothman, M. et al. “The Grass-Fed Milk Story: Understanding the Impact of Pasture Feeding on the Composition and Quality of Bovine Milk.” Foods, 2019.

Gerbault, P. et al. “Evolution of Lactase Persistence: An Example of Human Niche Construction.” Philosophical Transactions of the Royal Society B, 2011.

Küllenberg de Gaudry, D. et al. “A1- and A2 Beta-Casein on Health-Related Outcomes: A Scoping Review of Animal and Human Studies.” European Journal of Nutrition, 2022.

Kiesswetter, E. et al. “Effects of Dairy Intake on Markers of Cardiometabolic Health in Adults.” Advances in Nutrition, 2023.

Rosa, D.D. et al. “Milk Kefir: Nutritional, Microbiological and Health Benefits.” Nutrition Research Reviews, 2017.

Australasian Society of Clinical Immunology and Allergy. Lactose Intolerance.