Sunday, March 27, 2011

Poor Understanding - Raw Milk in New Zealand

Last week, I read an interesting article by Jill Galloway in the Manawatu Standard entitled "Selling milk as it was meant to be".  The story was about the increasing sales of unpasteurised and non-homogenised milk at the farm gate.  Unfortunately, the author and/or her interviewees made a number of errors.

Under New Zealand law, sales of raw milk from the farm gate have been permitted for several decades.  All other milk and milk products must be pasteurised or given an approved alternative treatment. Section 11A of the Food Act 1981 allows for producers to sell up to five litres of raw milk at any one time from their farm gates to people who intend to consume it themselves, or to provide it to their families.  However, the milk must be harvested under an approved Risk Management Programme under the Animal Products Act 1999.

So if farmers follow the rules, there should be no problem about safety.

However the article went on to express some strange views.

For example: "People believe in the integrity of food.  People want to know where it comes from. Processing destroys dairy products".

Or how about: (Farmers) "are up against rules, regulations and science".

But my favourite was:  "Before processed milk, there was no heart disease. Homogenisation means the fat particles are small enough to be ingested, not digested, and go straight through to the blood and arteries," Ms M. says. She thinks homogenisation began because people thought the fat on the top of milk was bad and they did not want to see it.

Hang on a minute.  If Ms M. is correct, then the dairy companies are actually delivering what consumers are demanding.

Second place goes to Farmer C: "When it is pasteurised, the milk becomes dead. People don't want to be eating or drinking dead stuff."

So you never had a steak, Mr. C?

I guess I should not poke fun at these people, who genuinely believe that their product is better than pasteurised milk.  And indeed, they are producing their product according to the NZFSA regulations.  But it does worry me that people can be so smart in some aspects of their lives but authoritatively make such ignorant statements.


Peter Bradley said...

Yes John you should poke fun. The spread of half truths and misinformation are the basis of silly decisions and eventually policy.

Helen Baron-St John said...

A letter to 'The West Australian' newspaper today refers to current threat to the local dairy industry by the two largest supermarket chains indulging in competitive price wars using milk as a loss leader, forcing down returns to farmers. It goes on to say that the local industry will soon be extinct and we shall be compelled to consume UHT milk. The writer argues that the treatment of UHT milk denatures proteins and reduces soluble calcium, thereby reducing it to "junk food". Perhaps you might consider commenting on these opinions? (You can access the newspaper online if you would like to read the full text).

John said...

Helen: UHT processing of milk yields a product with a much longer shelf life than pastuerised milk - typically 6 months.

There is the possibility of a defect called "age gelation", which may develop over time. This appears to be the formation of long chains of casein micelles that go on to form a matrix, increasing the viscosity of the milk. The exact cause is not known, but it may involve the natural plasmin enzymes of the milk, or heat-stable bacterial enzymes that survive the process. Other possibilities are aggregation of the micelles because of chemical reactions.

The suggestion that calcium becomes less available refers mostly to overheated milk, where the rates of Maillard reactions increase. Maillard reactions occur between amino acids and reducing sugars (these are important in some foods, such as baked goods, because they develop colour and flavour).

From my comments above, you can see that it is important to control high temperature processing of milk carefully.

Anonymous said...

I am not sure that anyone knows why milk was homogenised originally. It may have nothing to do with the cream. Not sure why the comment was made. Nowadays people are realising that cream is important as is anyway, so rermoval is no longer delivering to a need to all.

The comment about "dead" does also hold true on steak. The animal which the steak comes from is dead but I think we could find lots of life in raw steak, when it is taken off the beast. The enzymes for digesting it will still be there until it is frozen or cooked. This is why there is a raw food movement.

I am sure that whatever farmers say can be seen in a "strange" light by microbiologists or non farmers as they basically live in a different universe!!

However raw milk is better than pastuerised because it contains constituents that are useful to the human body and digestion, that are definitely destroyed by pasteurisation eg lactase. How come microbiologists are extracting some of these useful items so that dairy companies can sell them separately from milk at higher rices

John said...

I published the comment from Anonymous in the spirit of true debate.

Homogenised milk still contains some of the original fat. The homogeniser simply breaks the fat globule membrane so that the cream doesn't separate and float to the top of the milk.

Normal healthy people don't need enzymes from meat to be able to digest it. The stomach contains powerful proteases that break down proteins. Fats are then emulsified by bile and digested in the small intestine. There may be some benefits to eating raw foods, particularly vegetables and fruit, but I would suggest that consuming raw meat is unnecessary and possibly dangerous because of the other "life" in it i.e. potentially pathogenic bacteria.

Being a microbiologist and a farmer and not mutually exclusive - I have owned and operated a farm for the last 23 years.

I have never heard of lactase being found in milk. Humans produce lactase predominantly in the enterocytes lining the villi of the small intestine.

Anonymous said...

Sorry to be "annonymous" But there do not seem to be enough choices to be anythiung else, I must be blog illiterate!! So you can also laugh at me.

Thanks for the debate you seem to have recognised that steak is still not dead until cooked. You seem to advocate cooking. You seem to have also accepted that the cream is mixed up somehow in homogenising. I suppose you may also agree with GE.

There is definitely lactase in milk, it is the test for pasteurisatrion that lactase is no longer present. I have confirmed that with a lab person whose job it is to check that for a processor. As people age they loose the ability to produce lactase, also others obviously are not as able to produce it and become lactose intolerant.

I obviously omitted a huge long list of other constituents that are also destroyed by pasteurisation and yet are beneficial.

I will recommend this blog to lots of other farmers and microbiologists.

John said...

I think perhaps your lab person is confusing the names of enzymes. The test for successful pasteurisation is to test for alkaline phosphatase activity - if this is inactivated, the milk is considered properly treated to destroy the most heat resistant non-sporeforming bacteria likely to be found: Mycobacterium tuberculosis and Coxiella burnetii.

Anonymous said...

This is a different anonymous from above. I'm curious if those advocating the drinking of unpasteurized milk would also advocate the drinking of fresh blood. Quite curious. There are many many enzymes in blood.

Or feces. I'm guessing the number of enzymes to help break foods down would be extremely high in feces. No doubt this would have to aid in the process of digestion.

Or all three really. It would be easy enough to add some poo on site while collecting the milk, it's only a hop skip and a jump away. A little blood letting could also easily be done.

Call it a milkburger? Hmm...

Anonymous said...

As I understand it, yes our bodies produce enzymes however enzymes are produced for more than just eating - the immune system being highly reliant on enzymes for example. When the food we eat is processed then our bodies have to do all the work at the expense of the other parts that also need enzymes as there is only a limited rates that our bodies can produce them. When we eat unprocessed food digestive enzymes come with the food making it much easier to digest without creating undue enzyme load.

John said...

Thanks Anonymous July 8 2011
I'm assuming that you are not entirely serious in your suggestion, but I suppose that is carrying the argument to its logical conclusion.

John said...

Anonymous July 8, 2011
I delayed posting your comments while I thought about them. I have now published them, again in the spirit of true dialogue.

When we eat food, our intestinal system digests the food using enzymes and other chemicals secreted into the digestive tract. This does not take away enzymes from other cells in the body and there is no need to eat unprocessed foods to relieve stress on other organs.

The breakdown products of digestion are absorbed into the blood and transported to various parts of the body for generation of energy and construction or repair of cells. Some parts of the food are used by bacteria in the intestine and processed further, yielding useful compounds, such as Vitamin K2, which we can then use.

Consumption of a balanced diet, containing meat, vegetables, cereals and fruit, should ensure that every organ in the body receives the nutrition it requires.

Jayson said...

John, poking fun at people who stand behind their beliefs is pretty small minded and ignorant of you. At the end of the day your asumptions and opinions are based on what you've studied in some institution and who's to say they are right? Who says your right?
I'll stick to raw milk, enjoying the fantastic taste and enjoying the health benefits. While you keep drinking tasteless homogenized and pasteurized milk, enjoy your heart disease and clogged arteries.

Anonymous said...

I am an advocate for RAW Milk in New Zealand.

1) The overriding issue is freedom of choice.
2) MAF is prepared to accept a buyer risk situation.
3) Direct sales from farmer to consumer are essentially the same as farm gate sales
4) Delivery is not inherently risky as long as a chilled means of transport and storage can be guaranteed.
5) Visiting the farm for each collection does not necessarily confirm hygiene any better than occasional visits to the farm
6) Suitable regulations can be written to provide for very low risk in drinking raw milk.
7) Risk in New Zealand is inherently low and getting lower.
8) Risk Assessment information to be provided to consumers
9)it tastes better than ice cream!

Anonymous said...

Poking fun at people who stand behind their beliefs is not small minded and ignorant when the beliefs are silly and ignorant.
Consider also that cooking was the technological step that improved the body's ability to digest food to such an extent that it enabled greater development of the brain, and thus the evolution of modern man and civilisation. Silly beliefs that "raw" and "natural" are better should be mocked when they are not founded on science.

Anonymous said...

The Maasai traditional diet consists of mostly raw milk products. They also drink a mixture raw milk and fresh cows blood. Heart disease is almost unknown.

The French eat large amounts of "raw" cheese made from unpasteurized milk. They mostly eat all the dairy fat in milk and other dairy products. Yet they are healthy, and scientists are a little stumped. Hence the term "the french paradox".

So as entire cultures and nations eat this stuff and somehow survive, in fact are thriving and in many ways have better quality of life than those living in countries that outlaw the sale of raw milk, the rest of the "developed" world continues to consume diets deemed "safe" by their Govt and big corporate farmers, while the citizens become obese, diabetic and develop heart disease and higher rates of cancer.

I am an Australian living in the USA, I have spent a bit of time in France, I drink raw milk from our own cow and there is not a govt microbiologist or food safety regulation in sight.

John Brooks said...

Thanks Anonymous 11th June.
I think it is important to draw the distinction between safe diet and potential food borne disease.

For example, the Maasai don't consume large quantities of soda and hamburgers. This might contribute to their absence of heart disease. But you don't say anything about the number of times they get food poisoning.

Similarly, the French consumption of raw milk cheeses cannot be solely credited with their health - there are many other factors.

You have an absolute right to drink raw milk from your own cow, but I don't believe that you should be able to market that milk to others and claim health benefits, nor should you encourage its consumption by children.

As for raw milk cheeses, the cheesemaking process will often ensure that pathogens are destroyed. But once again, certain types of cheese with high water activity,high pH and low salt may allow survival of pathogens, leading to food poisoning of consumers.

Anonymous said...

Anon 11th June responding to John:

I agree I have no idea how often the Massai contract food born illness, and I'm not advocating anyone be forced to use their diet. I'll leave the monopoly on the legal use of force to the govt.

I would like food safety experts such as yourself to be advocates for raw food availability/choice, and find ways to do their job and keep people safe whilst consuming these foods which are definitely at least as nutritious and most probably healthier than the mass produced and homogenized dairy products which at the moment are the only option available to most consumers.

For example we want to consume fresh (< 60 day old) cheese made from unpasteurized milk and it is illegal in the US. This reduces our choice of cheese significantly. And for what reason? It can't be for food safety as the French are not more prone to illness from consuming dairy than the USA.

So our freedom of choice is to
a)move to France
b)become an outlaw and import on the black market
c)maintain our own dairy cow and make the cheese ourselves (We can't make cheese from commercially available milk as it is pasteurized, and there are no dairy's nearby, and in any case it is would be illegal for them to sell unpasteurized milk for human consumption).

So we do have choices but I don't think anyone could characterize these choices as those that would be available in a free society.

Anyhow, thanks John for your necessary expertise (however narrow it might be)and your blog.

Australian living in USA.

Anonymous said...

I appreciate your expertise and time given to this blog, and this post was helpful through the third paragraph.

I agree with the anonymous Aussie living in the US that we all would benefit more from experts as yourself advocating healthy choices. Not saying you have to back every flossy article that strays from the facts, but to tear down advocates because you don't have the same opinion that "people believe in the integrity of food", just isn't that helpful.

And for the comment from farmer C:"People don't want to be eating dead stuff"... as a microbiologist and food specialist you would understand that the more you heat food/drink (yes, even steak) the more the protein structures change, nutrients die, etc. And he's right. I don't like all the "life" taken out of my food.

I liked when you stuck to the facts though. Thanks for the info.

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