Raw milk
From Free net encyclopedia
Raw milk is milk that has not been processed via pasteurization (heating) or homogenization before consumption by humans. The taste is different, and so is the digestability. There is no consensus as to whether it is more healthful or less, compared to regular milk.
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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 micro-organisms (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 pasteurization process also 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. Raw Milk Versus Pasteurized Milk.
- The beneficial bacteria (probiotics) promote good health by crowding out bad bacteria (competetive exclusion) and help prevent yeast overgrowth in the intestinal tract, such as of Candida.
- Enzymes are destroyed by pasteurization which would aid in digestion. Lactase is an enzyme (created by bacteria present in raw milk, but not pasteurized) that aids digestion of the milk sugar lactose, and so some lactose intolerant individuals can drink non-pasteurized fermented milk products.
- Raw milk will sour naturally due to the lactic acid producing bacteria (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 human collagen may or may not be able to absorb this from raw animal sources such as raw milk. In other words, it isn't known whether these diseases represent recent unfavourable mutations, or the survival of genes common before cooking and food processing.
Advocates of raw milk often promote:
- dairy cattle being organically grass-fed without hormones or antibiotics as the best means to produce healthy raw milk. This method has been shown to produce omega 3 fatty acids in the milk which is rarely found in large scale commercial dairy products. Not all raw milk comes from cows fed organic feeds, however.
- Whole milk and believe the fat in raw milk promotes good health.
Many raw milk dairies feature milk from Jersey cattle, which are smaller and produce the richest milk, or from Guernsey cattle, which are slightly larger, and produce slightly larger volumes of slightly less rich milk. Some raw milk dairies, however, raise Holstein cattle, which give huge quanities of less rich milk. Most milk in the US comes from Holsteins.
Buying milk directly from the farm typically means getting milk that is minutes old, or hours old at most, and if properly refrigerated, will keep 8 days, versus the 5-6 days for the much-handled pasteurized milk purchased in a supermarket. Raw milk providers must exercise sanitation on the farm, and healthier herds than pasteurized milk producers must maintain.
Views by opponents
The pasteurization process for milk was implemented specifically to kill common pathogens 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 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 has found that "raw milk, no matter how carefully produced, may be unsafe."
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. These are all human pathogens — they can cause disease in humans.
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.
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.
Products made using raw milk (such as cheese and yogurt) will contain the same bacteria as the original milk. These processing methods do not kill disease-causing bacteria. Between 2001 and 2004, tuberculosis from raw milk cheese caused the death of one infant and sickening of dozens of people in New York City.
Buying "certified" raw milk is no guarantee that the milk is disease-free: many documented cases of salmonella dublin infection in humans have been caused by consumption of infected certified raw milk. Certification of raw milk is performed by a dairy industry association, not by public health authorities.
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 your 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 [1], but are coagulated upon boiling, which explains the different consistency of boiled milk. In regard to total elimination of casein from one's diet, see gluten-free, casein-free diet for more information on reported effects of this particular diet.
Homogenization and Heart Disease
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."2 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
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 US Public Health Service in 1924. The four states that have not include both Pennsylvania and California, big milk-producing states, as well as New York and Maryland.
That doesn't 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. Youngs not only offered raw whole milk, but skim milk, cream, butter, and ice cream made from their own raw milk. Jersey cows are a breed known for producing smaller quantities of exceptionally rich milk; most dairy farmers raise Holsteins, which produce huge quantities of thinner milk.
Raw milk may be purchased from the farm, under varying restrictions, in 28 states. 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 fairly easy for dairies to begin selling raw milk on the farm, and when the farm economy periodically suffers, new producers enter the marketplace. The state requires far more frequent inspections and lab testing of raw milk producers, however, and while farmers frequently begin selling raw milk, many soon abandon it, finding the cost and effort of handling milk properly and keeping the herd healthy to be unacceptable.
External links
Supporters of raw milk
Opponents of raw milk
- Why Raw Milk Should Be Avoided - Stephen Barrett, M.D.
- British Columbia Ministry of Health: Raw Milk - A Risk to Public Health
- U.S. FDA Center for Food Safety and Applied Nutrition: Position statement on sale/consumption of raw milk
- CDC: Highly increased risk of contracting salmonella dublin infection from raw milk
- University of Guelph Food Safety Network: Summary of raw milk disease outbreaks
References
- Oster, K., and Ross, D. "The Presence of Ectopic Xanthine Oxidase in Atherosclerotic Plaques and Myocardial Tissues." Proceedings of the Society for Experimental Biology and Medicine, 1973.