Milk – History and Safety
Milk is a food that is unique in that its primary purpose is to nourish a growing mammal. Animal milk is a traditional food that has been consumed for thousands of years in many varied cultures (Rose, 2015). Because milk spoils very quickly, it has usually been fermented or cultured for long term storage. The culturing of milk not only inhibits spoilage, but effects a transformation that changes its qualities, both in taste, and in nutritional value.
Milk is widely accepted as being a nutritious food, containing many healthy fats, proteins, and vitamins, but also can be problematic for some people. Many are intolerant to lactose because they are unable to produce suficienct amounts of the lactase enzyme. Others are allergic to the casein protein molecule. Milk consumption, particularly cow’s milk is sometimes blamed for childhood ear infections and allergies, and many question whether it should be consumed at all by adults.
Milk naturally contains enzymes and bacteria, and can easily be infected by pathogenic bacteria such as salmonella, listeria, E. coli, and cryptosporidia. The process of pasteurization destroys bacteria, both good and bad, but the Centers for Disease Control and Prevention (CDC) claims that the nutritional benefits of milk are not significantly changed by this process (CDC, 2015). Most store-bought milk is homogenized, a process that forces the milk through small holes that break the fat droplets into small particles, so that the milkfat mixes smoothly in the milk. While this may be convenient for the consumer who doesn’t want to shake the carton of milk before opening it, homogenization breaks down the delicate lipid bilayer around the fat molecule, allowing nutrients to react to each other, resulting in their degredation. Pasteurizaton degragades the amino acids lysine and tyrosine, destroys vitamins C, B12, and other vitamins. The destruction of enzymes decreases digestibility and puts a greater stress on the pancreas, which might explain the link to diabetes (Fallon & Enig, 2003). The more milk is processed, the less nourishing it becomes, as fats, proteins, and carbohydrates react to each other, and the once easily assimilated nutrients turn into a matrix of compounds that are foreign to the body (Shanahan & Shanahan, 2009, p. 158).
The pasteurization of milk is a very contentious issue in some areas. Raw milk is very regulated, and in many states is illegal to sell to consumers. The CDC strongly warns consumers against the consumption of raw milk, saying that it is one of the riskiest of all foods, and consumption could result in serious injury or death (CDC, 2015). However many doctors and food experts claim that the safety of raw milk is very good if handled correctly, and has health benefits that greatly outweight its risks.
A serious fallacy of our higene-obsessed culture is associating cleanliness with sterility. Pasteurization is no guarantee of cleanliness, and many large outbreaks of illness were caused by pasteurized milk. Often pasteurization can be a substitute for cleanliness, since poor sanitation can be remedied by sterilization or disinfectation. My father has been a dairy inspector for many years, and he reports seeing farms that were obviously unsanitary, but always tested suspiciously low in bacteria. He suspects bleach or hydrogen peroxide was added to the milk to lower bacteria count, but this would be difficult to prove.
Naturally, the thing that should halt the proliferation of bad bacteria is good bacteria, and pasteurization the good, bad, and beneficial enzymes. Sterile, germ-free milk is less healthful and can still spoil. The most natural, healthy form of food preservation is fermentation, where the growth of good bacteria is promoted. This naturally inhibits the growth of pathogenic bacteria, without the damaging effects of heat. This has been tradititionally done with milk by making cheeses, kefir, and other cultured products.
If pasteurization laws were eliminated, it would facilitate the purchase of food directly from farmers. A tenant of the local foods movement is the importance of consumers having knowledge and connection to the source of their food. This would reduce transportation and processing costs, eliminate the middleman, and would allow farmers to get much better prices for their products (Harris, 2003).
The arguments in favor of raw milk consumption center on freedom of choice, and the idea that raw milk is consumed naturally, “as God intended” (Chaya, 2015). However, even a casual observation reveals the fallacy of this argument. Driving to a grocery store to buy a BPA-infused hydrocarbon-encased carton of anything isn’t completely natural. In nature, raw milk is drunk by babies who ingest it directly from the source, without packaging, without transportation, without refrigeration. Not only unpasteurized, but it doesn’t get the chance to be exposed to the air where it can oxidize, so it’s as fresh as it can possibly be. On the other hand, cow’s milk is designed by God to nourish a cow, not a human. The first chamber of a cow stomach, the rumen, is a fermentation chamber designed for breaking down fiber by bacteria which convert the long chain polysacchrides to short-chain fatty acids. When a newborn calf drinks from its mother, its head is lowered and the next is extended upward. In this way, the folds of the throat fold into a straw that directs the warm, fresh milk directly into the true stomach (the abomassam), bypassing the other three chambers of the stomach where the delicate nutrients would be degraded (Thomas, 2009, p. 166).
Whole milk has a milkfat of about 3.5%. Low fat and skim milks have the fat removed to be used for cream, butter, and other products. Skim milk could be considered a waste product of the butter industry. Skim and low fat milk is less healthful, since fat is needed for building and maintaining nerve and brain health, and to transport fat-soluble vitamins. Fats are structures of cell membranes, and are necessary for hormone production. Milkfat contains important health-supporting nutrients including trans-palmitoleic acid, butyrate, phytanic acid, and conjugated linoleic acid (CLA). People who consume full-fat dairy have lowest risks for obesity, diabetes, and heart disease. Skim milk consumption is not associated with these benefits, and may actually be harmful (Kresser, 2014). A survey of European farming communities revealed that exposure to stables and raw milk had a strong protective effect against development of asthma, hay fever, and atopic sensitisation (Riedler, et al., 2001).
The quality of cow milk is in part determined by the health of the cow. Cattle that are raised outside on pasture eating fresh grass, enjoying sunlight, and breathing fresh air are going to be healthier than those living in a feedlot, eating junk food, and being injected with antibiotics to keep them healthy enough to pass inspection.
Certain cattle decended from European breeds, including Holstein and Friesian are known as A1 breeds. A1 cattle are distinguished by a genetic mutation that results in an altered casein molecule released into the milk, resulting in the production of an opioid molecule, beta-casomorphine 7 (BSM7). BSM7 is unnatural to humans, and in some studies have shown correlation to type-1 diabetes and heart disease (Betacasein.net). Although scientific literature has been published for more than a decade, most farmers I’ve spoken to claim to have no knowledge of the debate. Likely they don’t want to spend the money for genetic testing and culling cattle. Normal cattle are referred to as A2 breeds.
When buying milk, it’s a good idea to know the farmer, and the farming practices. Many large dairy operations have unsanitary practices, and use antibiotics as a substitute for good higene. These antibiotics have been linked to the rise in modern superbugs (Amy, 2013). Milk cattle have been bred to have higher than normal milk production, due to excessively large pituitary glands. Recently, growth hormones have been approved to artifically augment milk production. This makes the cow suceceptible to mastitis, and could cause health problems in humans as well. These artificial hormones have been banned in many countries, but are legal here in the US. For these reasons, I think it’s best to buy milk from farmers who are not using these practices, and if you buy from the store, look for the organic certification.
To summarize, both raw and pasteurized milk carry a risk of infection. The more a food is processed, the less nourishing it becomes. Milk, whether raw or not, should only be consumed from trusted farmers that have good sanitation and amimal care standards, and do not use artificial products. Butter, and cultured milk products such as kefir, yougurt, and cheese are traditional foods that are healthy, easy to store, and have low risk of infection.
Bibliography
Amy, S. (2013, Aug 27). How do artificial hormones and antibiotics figure into milk making? (They don’t on our farms!). Retrieved from The Yougurt Dish: http://www.stonyfield.com/blog/no-artificial-hormones-and-antibiotics/
Betacasein.net. (n.d.). Childhood (Type 1) Diabetes. Retrieved from Scientific Research on Beta-Caseins: http://www.betacasein.net/childhood.html
CDC. (2015, Feb 20). Raw Milk Questions and Answers. Retrieved from Centers for Disease Control and Prevention: http://www.cdc.gov/foodsafety/rawmilk/raw-milk-questions-and-answers.html
Chaya. (2015, Feb 2). The Rise of Raw Milk. Retrieved from Pantry Pratus: http://pantryparatus.com/blog/Risk-of-Raw-Milk/
Fallon, S., & Enig, M. G. (2003). Nourishing Traditions. Newtrends Publishing, Inc.
Harris, M. (2003, September). Got Milk? Vegetarian Times. Retrieved from Vegetarian Times.
Kresser, C. (2014, December 9). Still Think Low-Fat Dairy is the “Healthy Choice”? Think Again! Retrieved from Chris Kresser: http://chriskresser.com/still-think-low-fat-dairy-is-the-healthy-choice-think-again/
Riedler, J., Braun-Farlander, C., Eder, W., Schreuer, M., Waser, M., Maisch, S., . . . Mutius, E. (2001). Exposure to farming in early life and development of asthma and allergy: a cross-sectional survey . The Lancet.
Rose, A. (2015). Amasi: African Fermented Milk. Retrieved from Traditional Foods: http://www.traditional-foods.com/food-preservation/amasi/
Shanahan, C., & Shanahan, L. (2009). Deep Nutrition – Why Your Genes Need Traditional Food. Lawai, HI: Big Box Books.
Thomas, H. S. (2009). The Cattle Health Handbook. Storey Publishing, LLC.