Raw milk

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Raw milk is milk that has not been processed via pasteurization or homogenization before consumption. The taste and digestibility are different, but there is no consensus as to whether it is healthier than processed milk.

This article or section deals primarily with United States and does not represent a worldwide view of the subject.
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Contents

[edit] Pasteurization

[edit] Views by supporters

Proponents believe that it preserves the natural flavors, and claim that calves fed pasteurized milk die before maturity. They believe that:

  • The pasteurization process kills most, if not all, resident microorganisms (including beneficial ones that aid in its digestion and metabolization) and many nutritional constituents. The resulting pasteurized product causes digestive problems, is less nutritional and turns rancid (as opposed to souring) when aging.
  • The beneficial bacteria (probiotics) promote good health by crowding out bad bacteria (competitive exclusion) and help prevent yeast overgrowth in the intestinal tract, such as of Candida.
  • Pasteurization enables the milk industry to raise cows in less-expensive, less-healthy (constrained, crowded and filthy) conditions. Organic raw milk produced in such industrial conditions would, as critics charge, be very unhealthy. [1].
  • Enzymes are destroyed by pasteurization which would aid in digestion. Lactase is an enzyme created by bacteria present in raw milk, but not in pasteurized milk, that aids digestion of the milk sugar lactose. Many lactose intolerant individuals can drink unpasteurized dairy products for this reason.
  • Raw milk will sour naturally due to the bacterial production of lactic acid (such as Lactobacillus acidophilus), and still be healthy, whereas pasteurized milk, which lacks the healthy bacteria, will only putrefy.
  • People with genetic connective tissue disorders (such as Ehlers-Danlos syndrome) that prevent them from making at least one protein in collagen, may be able to absorb this from raw animal sources such as raw milk.

Advocates of raw milk often promote:

The majority of the milk in the U.S. comes from Holstein cattle, which produce the most milk of all common cow breeds. Some raw milk dairies raise Holsteins, but many raw milk dairies feature milk from Jersey cattle, which are smaller than Holsteins and produce milk higher in butterfat, or from Guernsey cattle, which are slightly larger than Jerseys, and produce larger volumes of less-rich milk.

A great deal of raw milk is purchased directly at the farm, due to legal restrictions regarding sale at stores. Buying milk directly from the farm typically means getting milk that is only a few hours old. If properly refrigerated, raw milk will keep 8 days, versus the 5-6 days for the much-handled pasteurized milk purchased in a supermarket.

[edit] Views by opponents

The pasteurization process for milk was implemented specifically to kill common pathogens, believed to have been transmitted by milk, and secondarily, to give milk a longer shelf life by reducing the number of spoilage-causing organisms. The most significant diseases transmitted by milk are salmonellosis, brucellosis, tuberculosis, and campylobacteriosis.

Opponents, including the US Food and Drug Administration (FDA) and the group Public Citizen, cite the dangers of pathogens and dispute the health claims. Owing to the lack of pasteurization, raw milk must be produced under strict sanitary conditions, has a shorter shelf life and must be maintained consistently at a low (<40°F) temperature. Despite the restrictions and conditions imposed on producers of raw milk, the FDA states "raw milk, no matter how carefully produced, may be unsafe."

Raw milk is frequently promoted as a "health food," especially to those who are already ill or have compromised immune systems, such as patients with cancer or AIDS. The additional load presented to the immune system from disease-causing bacteria present in raw milk can be too much for the body to bear. A notable opportunistic infector of elderly and immunocompromised patients is Salmonella dublin.

Between 2001 and 2004, an outbreak of tuberculosis, which health officials believed to be from unlabelled, illegally imported, Mexican soft raw milk cheese, caused the death of one infant and sickening of dozens of people in New York City. [2]

Some people say that pasteurized milk converts the protein casein into beta-casomorphin-7, which some in turn link to autism. This argument is based on incorrect knowledge of casein digestion. The process of human digestion, not pasteurization, converts casein into casomorphins (including beta-casomorphin-7) regardless of whether the consumed milk product was pasteurized. Since a person's body creates these byproducts from any casein it encounters, it makes no difference as to the source of the casein, be it from raw or pasteurized milk, cheese, yogurt, etc. In addition, casein and casein micelles are not degraded by pasteurization temperatures [3], but are coagulated upon boiling, which explains the different consistency of boiled milk. In regard to total elimination of casein from a person's diet, see gluten-free, casein-free diet for more information on reported effects of this particular diet.

[edit] Diseased cows

Cows with mastitis, an infection of their breast tissue, pass the infecting bacteria into their milk. The most significant bacteria causing bovine mastitis are Streptococcus agalactiae (and other streptococcus species), Staphylococcus aureus, various species of Mycoplasma, and coliform bacteria, all of which are human pathogens.

Cows that carry internal salmonella infections, especially Salmonella dublin, can shed the bacteria in their milk, despite external washing and cleaning of their udders. In addition, many kinds of bacteria can continue to reside on the udders' surface after washings, including salmonella and staphylococcus.

Buying "certified" raw milk is no guarantee that the milk is disease-free: some cases of Salmonella dublin infection in humans have been caused by consumption of infected certified raw milk.[citation needed] Certification of raw milk is performed by a dairy industry association, not by public health authorities.

[edit] Homogenization

Most of the raw milk debate traditionally has focused on pasteurization. Historically, most producers have not homogenized their milk because of the large investment in the required equipment, and for marketing reasons: milk with the cream floating on the top seems more natural.

In recent years, however, there has been increased attention placed on the health significance of homogenization. Dr. Kurt A. Oster's studies from the 1960s to the 1980s suggest that homogenized milk is a major factor in plaque formation, causing heart disease.

Atherosclerosis begins with a small wound or lesion in the wall of the artery. Oster reasoned that the initial lesion was caused by the loss of plasmalogen from the cells lining the artery, leading to the development of plaque. He believed that the enzyme xanthine oxidase (XO) has the capacity to oxidize, or change, plasmalogen into a different substance, making it appear that the plasmalogen had disappeared.

Oster and partner Ross investigated cow's milk, "…presently under investigation in this laboratory since it has been shown that milk antibodies are significantly elevated in the blood of male patients with heart disease." Homogenization became widespread in the United States in the 1930s and nearly universal in the 1940s - which is when atherosclerotic heart disease began to skyrocket. Oster theorized that the homogenization of milk somehow increased the biological availability of xanthine oxidase.

Oster asserted that XO is found on the membrane of the fat globules in milk. Homogenization, on the other hand, would encapsulate the XO, so that it would not be digested in the stomach and intestines, but enter the bloodstream, where it caused its damage.

Auguste Gaulin's 1899 patent on homogenization forced milk through fine holes to reduce the size of fat globules. At 15 MPa, pasteurization multiplies the fat globules 600-fold in number, while reducing mean size from 3.3 to 0.4 micrometres.

Neither opponents nor proponents of the xanthine oxidase/plasmalogen hypothesis have presented convincing evidence in all of their writings, but the debate is hardly over. Research by RJ Hajjar and JA Leopold resulted in the 2006 study, "Xanthine oxidase inhibition and heart failure: novel therapeutic strategy for ventricular dysfunction", published in the American Heart Association journal Circulation Research

[edit] Legal restrictions

Most states in the United States impose far more restrictions on raw milk suppliers than on the suppliers of pasteurized, homogenized milk. Of the 50 states, 46 have passed the Pasteurized Milk Ordinance proposed by the United States Public Health Service in 1924 - every state but Pennsylvania, California, New York, and Maryland.

That does not mean raw milk is unavailable in the other 46 states. In Indiana, for instance, it is illegal for a dairy to sell raw milk, but consumers are able to lease cows and obtain raw milk that way.

In Ohio, state law prohibits dairies from selling raw milk unless they had continuously offered it since before 1965. Raw milk was available until 2003, when the state pressured Young's Jersey Farm in Yellow Springs, Ohio into voluntarily giving up their raw milk license, by threatening them with loss of their pasteurized milk license as well. The state was experiencing an outbreak of salmonella which affected some employees at Young's, but which was not traced to Young's products. Young's not only offered raw whole milk, but skim milk, cream, butter, and ice cream made from their own raw milk.

Raw milk may be purchased from the farm in 28 states, under varying restrictions. In California, Connecticut, Maine, New Mexico and South Carolina, it may be purchased in stores. In every state but Michigan, raw milk may be purchased "for animal consumption."

In Pennsylvania, it is easy for dairies to begin selling raw milk on the farm. The state requires frequent inspections and lab testing of raw milk producers, and while many farmers begin selling raw milk, many soon abandon it, finding the cost and effort of handling the milk properly and keeping the herd healthy unacceptable.

The sale of raw milk directly to consumers is prohibited in Canada. [4]. However, Canada, and all 50 United States, permit the sale of raw milk cheeses that are aged for at least 60 days.

[edit] Related pages

Some raw food diets include raw milk.

[edit] External links

[edit] Supporters of raw milk

[edit] Opponents of raw milk

[edit] References

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