The liquid of life
In the natural order we see lots of animals getting their start in life by drinking milk. Thousands of years ago, agriculture caught on in earnest and ruminants (herbivores) were added to the lists of assets for food sources. A few millennia have passed now, and thousands of recipes have been handed down for this same simple raw material—milk.
What is milk? “Milk is partly an oil-in-water emulsion, a dispersion of tiny butterfat globules suspended in water” (Joachim & Schloss, 2008). About 80% by volume of milk is the structure called “micelles” which are composed of casein protein and calcium phosphate, the remaining components are lactose (milk sugar), living white blood cells and assorted enzymes (Joachim & Schloss, 2008). The proportions of those ingredients will vary by the breed of cow, diet, time of year along with other factors, but milk may just be the perfect food—probably why mammals start out on it.
There has been a lot of discussion whether or not mammals (aptly named for the milk producing glands to feed babies), people in particular should drink dairy milk at all. The arguments for this are varied and can be markedly biased from the originating source. Some groups say that humans are the only species to drink milk after infancy. Okay, I get—I think. No wait, actually I do not, because humans are the only ones building Space Shuttles or conducting agriculture in the first place. Others object because dairy for humans is made available by depriving the calves of the mother’s milk. I checked with grass-fed dairy Trader’s Point Creamery in Zionsville, IN and they do in fact keep their calves with the mother cows for five months until the calves are weaned. Evidently not all milk is produced by withholding it from the young—this may sadly be true of feed lot CAFO milk, but not of small family operations who respect the cowness of the cow.
So what of humans and milk? Human breast milk in comparison to other mammal’s milk may lack in protein but is far superior in lactose, a rich source of calories, which seems to be ideally designed for babies (see above table). Yet people continue to drink milk both as adolescents and adults; noteworthy to point out is the fact that this is not a European or Western phenomenon of “dairy bias.” People have long adopted the unassuming herbivore as a supplement to daily nutrition needs by converting sunshine into grass and grass into food in the most remote corners of the globe as depicted here in this account by the Weston A. Price Foundation in Mongolia. If milk were truly “against nature” it seems like these untouched populations would have been able to discern nature’s signal without outside industrialized new world interference.
Following the contemporary orthodoxy of all good food must be 100% sterile, milk processing is truly a wonder of modern industrialization. This is rather ironic because milk that is sold raw from grass fed cows (bearing the rich creamy tint of carotenes from the vegetation diet) is far from sterile—no one contests that. Yet milk from large production grain-fed dairies ends up being sterile for our safety. Understanding the nuance is important: zero anti-biotics and low animal density for grass fed raw milk and copious anti-biotics, high animal density for feed lot milk. In my podcast interview with Dr. Bones and Nurse Amy, the good Doctor mentioned that 80% of antibiotics produced in the United States are given to animals (McKenna, 2010)*. This is simply staggering. Grass fed dairy do not need it, feed lot dairy cannot live without it!
Often times Louie Pasteur gets implicated in the process named after him, “pasteurization.” Actually, he developed the method to help save a crop of grapes from yielding vinegar instead of the intended wine. The process proved so effective that it later was adapted to dairy milk and became the law to pasteurize all milk in Chicago in 1908 (Cellania, 2011).
The objective of pasteurization is to kill or deactivate all disease-causing microorganisms by “cooking" them. . . . Traditional pasteurization, originally intended primarily to kill tuberculosis bacilli, involved hearing the milk to 145-150˚F and holding it there for 30 minutes. Traditional pasteurization isn’t used much anymore, because it doesn’t kill and deactivate heat-resistant bacteria such as Lactobacillus and Streptococcus. That’s why ordinary pasteurized milk still has to be refrigerated (Wolke, 2002).
Modern dairy pasteurization is done much quicker and the milk is instantly cooled back down to preserve freshness. There is such a thing as ultra-pasteurization to achieve shelf stable milk in aseptic packaging—but that is another matter altogether.
The last milk processing step is homogenization. If you have ever seen raw milk you will immediately notice that it has a layer of delicious cream on top. In order to get milk to be uniform or homogeneous dairy operations have to break the fat globs in the milk.
If the fat globules could be chopped up into small enough “globulettes”—around 80 millionths of an inch in diameter, they wouldn’t rise; they would be kept suspended in place because water molecules would be bombarding them from all directions. To accomplish this, the milk is shot out of a pipe at a pressure of 2500 pounds per square inch at a metal sieve, coming out the other side as a fine spray containing fat particles tiny enough to say suspended (Wolke, 2002).
For thousands of years and across tens of thousands of recipes, milk has proven to be quite the utilitarian building block. For me, not only does milk comprise my favorite beverage, it also is a fundamental component of my favorite treat—milk chocolate, ditto for ice cream and milk with cookies.
Milk, it truly is a wonderful and amazing food. No matter what the critics say about milk, I will continue to add milk into my diet partly because I love it, partly because it is good for me.
Pro Deo et Patria
Joachim, D., & Schloss, A. (2008). The science of good food. (p. 402). Toronto: Robert Rose.
Table: Ibid, P. 401
McKenna, M. (2010, December 24). Wired. Retrieved from http://www.wired.com/wiredscience/2010/12/news-update-farm-animals-get-80-of-antibiotics-sold-in-us/
*Can corroborate that same statistic here:
*and also here:
Cellania, M. (2011, January 24). Neatorama.com. Retrieved from http://www.neatorama.com/2011/01/24/the-fight-for-safe-milk-pasteurization/
Ibid, P. 90
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