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The US Dairy Council On Milk Safety And The Raw Milk Movement

I recently discussed the emerging black market for raw (unpasteurized) milk and the FDA’s crackdown on California farmers. Soon after I posted my comments, a reader asked some detailed questions about heat, enzymes, and milk’s nutritional value. At the same time I received an email from the Vice President of Nutrition Affairs-Health Partnerships at the National Dairy Council, offering to connect me with a dairy product scientist to further the discussion. Isn’t it nice when all the stars align correctly?

I just interviewed Gary Rogers, Ph.D., the Editor-In-Chief of the Journal of Dairy Science and Professor of Animal Science and Dairy Extension Leader at the University of Tennessee in Knoxville. You may listen to the podcast, or enjoy my synopsis below:

Dr. Val: What is pasteurization?

Dr. Rogers: Pasteurization is the heating of milk to a specific temperature for a specified period of time to kill harmful bacteria that may be living in the milk.

Dr. Val: Raw milk enthusiasts argue that pasteurization decreases the health benefits of milk. What exactly is lost when milk is pasteurized?

Dr. Rogers: There are really no important changes that occur (from a nutritional standpoint) to milk when it’s pastuerized. Heat treatment is simply used to kill the bacteria that may present a health risk to those of us who consume milk. Research over the years has shown that there are no significant nutritional benefits to raw milk, but there are risks associated with exposure to bacteria.

Dr. Val: Some people say that raw milk is easier to digest than pasteurized milk. Is that primarily a myth?

Dr. Rogers: Yes, that’s a myth. There is no scientific evidence to suggest that raw milk is easier to digest than pasteurized milk. In fact, many people who have digestive difficulty with fluid milk can eat cheese and yogurt without any difficulty.

Dr. Val: I’ve heard some people claim that there are certain beneficial enzymes in raw milk that are destroyed in the pasteurization process. Is there any truth to that?

Dr. Rogers: There are dozens of enzymes in milk, but most of them are proteases that are involved in the break down of milk proteins and fats. While it’s true that heating can destroy some of these enzymes, they really have no role in human digestion. The enzymes are responsible for milk spoilage, so removing them extends the shelf life of the milk.

Dr. Val: Tell me about UHT milk (the boxed milk that is stored at room temperature) – does it differ -nutritionally and chemically - from pasteurized milk?

Dr. Rogers: UHT (or “ultra-high temperature”) milk undergoes a pasteurization process at a much higher temperature than regular milk. This increases its shelf life, but nutritionally and chemically it’s no different from regular pasteurized milk. It contains all the calcium, phosphorus, and protein of regular milk. However, UHT milk does have a different flavor that some Americans don’t like. In Europe, though, they really enjoy the flavor of UHT milk and often prefer to drink it over pasteurized milk. In the U.S. we use it for flavored milk products, and for military personnel who can’t keep their milk refrigerated as easily.

Dr. Val: I think the key confusion that people have here is that they think of heating milk like heating vegetables. We all know that when we boil vegetables for a long time the nutritional value decreases because their vitamins are removed in the water. However, with milk we’re essentially heating it without removing the “water” part.

Dr. Rogers: That’s exactly right.  Pasteurization doesn’t add or subtract anything from milk nutritionally, it’s just a heat treatment to destroy bacteria like listeria and salmonella.

Dr. Val: Are US cows exposed to antibiotics and hormones that could find their way into milk?

Dr. Rogers: I know that consumers are very concerned about these issues, but they need to know that every milk tanker is required by law to be tested for antibiotics. There’s a huge incentive for milk producers not to include milk from cows that may have been sick and treated with antibiotics because any tanker that’s found to have any trace of antibiotic in the milk will have its milk discarded. Not only that, but since tankers usually carry milk from multiple producers, one small contribution of contaminated milk will cause all the neigboring farms’ milk to be destroyed. So there’s a lot of peer pressure to keep the milk supply clean. Farmers who contribute milk from cows on antibiotics are fined for the losses of other producers’ milk as well.

As far as “hormones” are concerned, you’re talking about RBST (recombinant bovine growth hormone) to enhance milk production in cows. Although no lab test was ever able to distinguish milk from RBST treated cows from non-treated cows, consumers expressed such concerns about the practice that few milk producers use RBST anymore. I’d say that maybe 10-15% of dairy producers use it, and then it’s not for fluid milk sale, but rather cheese and other dairy products. Those numbers are continuing to decline.

Dr. Val: What does it mean when milk is labeled “organic?” Given the high price of groceries, are there advantages to purchasing organic milk?

Dr. Rogers: I work with both conventional dairy producers and organic dairy producers in my “day job” so I have friends on both sides. As far as nutrition and healthfulness is concerned, organic and conventional milk are equal. The “organic” label has to do with the production practices on the farms that produce the milk, not the properties of the milk itself. On organic farms, they do not use chemical fertilizers or pesticides to raise the crops that they feed to their cows. Some people like the idea of supporting organic farmers and consumers have every right to do that. But both organic milk and conventional milk are safe and equivalent nutritionally.

Milk is heavily regulated and controlled so that even on conventional farms, the pesticides do not get into the milk. All milk is tested for pesticides, and in my experience it has always contained far lower levels than the standard set for safety by the FDA.

Dr. Val: But isn’t it possible that the organic milk might have an even lower level of pesticides in it than conventional milk?

Dr. Rogers: Actually the tests that I’ve seen have not been able to distinguish organic from conventional milk as far as pesticide levels are concerned. However, I haven’t received results from all the organic farms in the U.S. But keep in mind that pesticides exist in such small quantities in milk that usually we can’t even detect them with the most sensitive instruments that we have in the laboratory.

Dr. Val: Is soy milk a good substitute for cow’s milk?

Dr. Rogers: It’s really hard to replicate the nutrition that comes from traditional milk sources. The calcium absorption, amino acids, vitamin, and mineral contents of milk provide a distinct advantage over soy milk, unless you have a specific dairy allergy. In a large recent study on baby formula, for example, there was no advantage to using soy based formulas over cow’s milk. People may prefer to use soy milk for its flavor, or because they support vegetarian food sources. But most soy milk is processed by dairy farms anyway.

*Listen to the interview with Gary Rogers*This post originally appeared on Dr. Val’s blog at

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4 Responses to “The US Dairy Council On Milk Safety And The Raw Milk Movement”

  1. ileana says:

    Dr. Val,

    I very much appreciate  you following up on my comments. 

    However, this answer made me wonder even more than before. I am no scientist, so I probably don’t know all the facts, but the answers did not convince me at all.

    “There is no scientific evidence to suggest that
    raw milk is easier to digest than pasteurized milk”

    But is there any scientific evidence to suggest that it’s not easier to digest? How do you measure easy to digest anyway?

    “In fact, many
    people who have digestive difficulty with fluid milk can eat cheese and
    yogurt without any difficulty.”

    “There are dozens of enzymes in milk,
    but most of them are proteases that are involved in the break down of
    milk proteins and fats. While it’s true that heating can destroy some
    of these enzymes, they really have no role in human digestion. The
    enzymes are responsible for milk spoilage, so removing them extends the
    shelf life of the milk.”

    That’s exactly the point. Aren’t cheese and yogurt made from “spoiled” milk? Aren’t maybe those enzymes that exist in cheese and yogurt, but not in the pasteurized milk the element that makes yogurt and cheese easier to digest? How do you know what has or hasn’t any role in human digestion? Is the digestion process as well known?

    In today’s world, I would be more convinced by someone that is more aware and more open with what is not known.  I am not drinking raw milk and would not give it to my kid either, and I listen to advice from my doctors and  the medical world at large because I think they have the best  information that exist at this time,  it is an informed decision and as good of a decision as can be made today.

  2. MichaelBrianFennertyMD says:

    Here are some musings on the “rhetorical” questions posed by one of your respondents. As to digestion, most milk is protein and carbohydrate as well
    as water. The

    “digestion” of milk protein and carbohydrate is
    not different than other

    food proteins and carbohydrates in that protein are broken
    down by

    specific enzymes (proteinases including pepsin, trypsin,
    etc. that are

    secreted into gastric juice in the case of pepsin and the

    intestine from the pancreas in the case of trypsin and
    others) as are

    carbohydrates (the principle digestive enzyme for the
    carbohydrate found

    in milk is lactase that breaks down lactose). This later
    enzyme is found

    mainly in the cells on the surface of the small bowel the
    site where

    most digestion and then absorption of short segments of
    proteins and

    free amino acids as well as products of carbohydrate
    digestion are then

    absorbed. There is no evidence that any
    “nutrients” are lost by

    pasteurization, nor can one hypothesize a reason they
    would be.  Perhaps

    most importantly the issue seems rather specious in
    concept, in that the

    overwhelming problem in the U.S. is the epidemic of
    “over-nutrition” not

    lack of available nutrients.  Perhaps if
    pasteurization actually did

    what these zealots propose, the obesity epidemic in the
    U.S. could be

    cured! Alas, as William Shakespeare once wrote, this is
    “Much Ado About


  3. SanFranciscoChiropractor says:

    This is interesting. I think your readers may be interested in this excellent article by Dr. John Mcdougall, MD,entitled: Marketing Milk And Disease

  4. bjohnsonrd says:

    Dr Val:

    I appreciate your willingness to listen to both sides of the story when it comes to “raw milk”.  As a Registered Dietitian and a mom I think it is critical to restate the fact that pasteurization is an essential food safety tool that makes milk and dairy foods unquestionably safe.  I worked for the local dairy industry for a number of years and I know and respect the processes that are in place aimed to ensure that milk and dairy foods are among the safest in the country.

    At a time when media reports of compromised food safety have us all on edge, it is nice to know that there is one thing in the refrigerator that I don’t have to triple wash before serving to my family.   

    Bonnie Johnson, MS, RD

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