There is nothing more bucolic and familiar in our imagination of a farm than the image of milking a cow by hand into a bucket, and then pouring a glowing glass of milk for two or three smiling children. How charming. How American.
There is a serious disconnect between that image and the reality of today’s dairy industry. Despite that deceptive fantasy, promoted by dairy companies and Little House on the Prairie books for decades, it was illegal to sell milk straight from the cow for most of the 20th century.
In response to that disconnect, more and more people advocate for drinking raw milk—milk that hasn’t been heated to kill bacteria. These advocates claim that raw milk provides numeroushealth benefits, that it ismore nutritious, that itprevents allergies and even cures acne.
Opponents, including the FDA and CDC, point to anincrease in cases of food poisoningfrom raw milk in states where raw milk is legal to sell, and warn that children under 5 years old are at greatest risk for illness.
Those are some pretty high stakes for a decision about what to pour on your breakfast cereal. Let me help you unpack some of the science, law, and propaganda about raw milk and look at the… ahem, raw facts.
什么是生牛奶?
Most milk that you buy in the grocery store has beenpasteurized—that is, heated to 161 degrees Fahrenheit for 30 seconds in order to kill microbes—orultra pasteurized, heated to 280 degrees F for 2 seconds. Theinvention of pasteurizationin the 1880s dramatically improved health outcomes from milk consumption. For example, pasteurized milk reduced the transmission of tuberculosis to the point where no one today thinks of TB as a foodborne illness.
Pasteurization kills microbes, harmful and otherwise, but it also denatures active enzymes in the milk and distinctly changes the flavor. Raw milk, as the name suggests, has not been heated, and retains the more complex qualities of untreated milk.
More visible advocacy for raw milk began in 1998, when an organization calledThe Westin A. Price Foundation,launched theReal Milk campaign,with the goal of bringing raw milk back to consumers. The campaign stresses the natural qualities of raw milk, which they say are more beneficial to consumers than the health benefits of pasteurization.
All baby mammals, including humans and calves, get a unique combination of microbes from their mother’s milk. Microbes help inoculate the infant calf’s gut with healthy bugs, as well as living white blood cells, to support the calf’s immune system and hundreds of active enzymes. Pasteurizing the milk destroys many of these benefits, while eliminating the risk of illness from harmful microbes.
During a laboratory class in college, fellow students and I cultured raw milk products in agar. We then compared the resulting bacterial growth to pasteurized milk and other processed milk products, including “probiotics” like yogurt and kefir.
Let me tell you, those raw milk cultures were some of the fuzziest petri dishes I have ever seen. What we found was that of all the cultures, the raw milk had the most active and diverse microbial growth. As expected, the store bought pasteurized milk and yogurt saw very little. (Interestingly, commercial yogurt and kefir advertised as “probiotic” and “live culture” did not demonstrate much microbe growth either.)
当然,食品科学201班的一项实验结果还远未得出定论,但毫无疑问,生牛奶中充满了活跃的微生物。今天,在一个发酵食品、益生菌和有益微生物日益流行的时代,这种微生物特征正使生鲜奶迅速成为明星。
生牛奶有什么好处?
Common claims about raw milk include that it is easier to digest, is more nutritious, and that the microbes help populate our guts with beneficial bacteria, potentially reducing the risk of allergies. However, there isno reliable, peer-reviewed evidencethat raw milk provides any health benefits other than what pasteurized milk can provide. That’s not to say they don’t exist, but modern scientific studies have yet to find them.
Digestion And Gut Health
Despite the intuitive claims that the enzymes and beneficial bacteria in raw milk help people with lactose intolerance to digest milk sugar, astudy from Stanfordfound that not to be true. Scientifically speaking, that result is not surprising: it is not microbes in your gut that digest lactose, it is the production of the lactase enzyme, which milk, raw or otherwise, does not contain.
生牛奶中的微生物是否像小牛那样帮助消化并支持健康的肠道生物群?有可能,但小牛是反刍动物,它们的消化系统与人类的肠道完全不同,它们需要非常不同的微生物来维持肠道健康。关于牛奶中有益微生物的炒作已经和益生菌食品的炒作混淆了。
Itistrue that fermented, cultured foods like kimchi, sauerkraut, yogurt, and kefir helpsupport gut health, as long as you buy them from reputable processors. However, those foods have been cultured with specific microbes, which produce acid or alcohol in the process of fermentation to kill harmful microbes and preserve the food.
Lactobacillusis a common microbe used in both vegetable and dairy ferments in cultures around the world, and it is very important to the health of the human gut. However, the much more complex mix of microbes in raw milk does not resemble the probiotic cultures of fermented foods, since the whole point of a successful culture is that a few microbes outcompete the rest, and it is not clear that this influx of microbes from raw milk benefits the human gut.
Nutrition
What aboutnutritional content? Pasteurization changes the composition of some of the protein molecules, but does not change their ability to be absorbed into the body, nor does it change the mineral content of milk.
Pasteurization does potentially lower the levels of vitamins in the milk but not by significant amounts. For a strong vitamin content in milk thecow’s diet is much more importantthan the treatment of the milk.
最有营养的牛奶是全脂牛奶,它主要来自动物吃的草或高质量的干草。2022欧洲杯葡萄牙vs德国
Flavor
However, unpasteurized milk has a couple of clear benefits that are not health-related. Heating milk changes the flavor profile, and many people who drink raw milk prefer the taste over pasteurized milk.
生牛奶也受到奶酪工匠的高度重视。由于微生物群落是人工奶酪制作的基础,生牛奶中复杂多样的微生物是奶酪制作者的工具和利益。
这种微生物创造出了一种更复杂、更独特的奶酪,这种奶酪无法用另一家奶牛场的另一头奶牛的牛奶完美复制。
This unique, place-based quality is calledterroir, and it is highly prized by artisan food craftspeople of all kinds, from cheese, to wine, to chocolate. Terroir is closely associated with unique microbial communities living in food, like raw milk.
People have personal preferences about milk as well. I know people who swear that raw milk is better digested by their bodies, and they know their own bodies best.
I have always found that raw milk upsets my stomach a little, which is also a common response in people who grew up drinking pasteurized milk, like me. There is no question that the active community of microbes in raw milk has an effect on the digestive tract, and people have to decide for themselves whether it is compatible with their body.
Is It Dangerous To Drink Raw Milk?
自从奶牛被驯化以来,世界上一些地区的人类饮用生牛奶已经有几千年的历史了,但这并没有导致该物种的灭绝。2022欧洲杯葡萄牙vs德国另一方面,巴氏杀菌大大减少了由食物中毒和食源性病原体引起的疾病和死亡。
Today the Center for Disease Control stronglyadvises againstconsuming raw milk because of the health risks it poses. And let’s be clear, people do occasionally get sick from drinking raw milk from legal, regulated operations.
However, from 1998 to the present, no one has died from consuming raw liquid milk. The twodeaths reported by the CDClinked to raw milk were both caused by raw queso fresco style soft cheese, one contaminated with salmonella, the other with listeria.
The most common harmful microbe found in raw milk isCampylobacter. It causes diarrhea, and isn’t life-threatening except in those with weakened immune systems. Other pathogens associated with raw milk include E. coli, salmonella, and listeria. All these microbes are common in livestock operations like dairies.
Cleanliness At Raw Milk Dairies
专业的生奶场知道与他们的产品相关的风险,并尽一切可能将危险降到最低。所有的奶牛场应该是干净的,但生奶牛场应该是一尘不染的。
A female dairy farmer who sells raw milk told me, “If I can’t wear my pink fuzzy house slippers into my milking parlor, it’s not clean enough.” Of course, a building can be clean enough to eat off the floor, but the minute you walk a cow into that room, she brings two thousand pounds of microbe covered farm animal. And she’s probably going to poop while you’re milking, just because she can. (I speak from experience).
然而,商业奶牛场使用的是真空挤奶机,它会吸到奶牛的乳头上,所以挤奶时牛奶不会暴露在空气中(或牛的粪便中)。This dramatically reduces exposure to microbes.
The most important thing is to ensure that the cow’s teats are cleaned and sterilized before milking begins, and of course, that the equipment is clean. I can confidently say that no one is milking into an open bucket for commercial sale of raw milk (or for any other kind of milk for sale for that matter). That technology, combined with a strict standard of cleanliness, can provide confidence in the safety of raw milk.
The bottom line is that there is always a risk of microbial contamination in raw milk. However, a responsible and educated farmer running a clean and well-regulated operation can reduce the risk of milk-borne illness significantly.
It is also worth noting that the two most deadly outbreaks of food poisoning in recent history have been fromfenugreek sprouts, andcantaloupe, so really, nothing is ever truly safe and it’s not worth living in fear.
What Are The Laws About Raw Milk?
如果你有一头奶牛,没有关于你如何处理和喝它的牛奶的规定。但一旦你想卖生牛奶,你就进入了复杂的法律领域。在美国,生牛奶的销售受到各州的监管。每个州都有不同的法规,由该州的农业部执行。
Permissive States: Farms Can Sell Milk
In the most permissive states, like Washington and California, raw milk dairies can sell to retail establishments, at farmer’s markets, or through any other licensed retail venue. Other states are slightly less permissive, and only allow raw milk to be sold on-farm.
Restrictive States: Herd-Shares Or Outright Bans
Still others, like Michigan and Colorado, allow raw milk sales but only through a herd-share arrangement. Multiple households to own shares of a cow, and the cow’s milk can be distributed to shareholders without being subject to additional regulations. In 16 states, it’s illegal to sell raw milk for human consumption. As tempting as it might be to buy milk from your neighbor in one of these states, do so at your own risk.
Check outthis interactive map查看各州关于生鲜奶的法律细节。
Ultimately, if you live in an area where you can buy raw milk legally, the choice about what is best for you and your family is entirely yours. Many people find raw milk more delicious and satisfying than pasteurized milk.
It makes people feel closer to the animal from which it came, and for people who milk their own animals, it’s frankly a lot less work to skip pasteurization.
My partner and I own a Jersey cow. We have always chosen to pasteurize her milk. For a while I felt like I was losing points as a foodie and a farmer when we did that, but in the long run, it was just the choice that worked best for my body, and our peace of mind.
The balance of science is against raw milk, because there are clear-cut cases of illness without clear-cut benefits on the other side of the scale. But, the bottom line is that raw milk from a licensed, inspected dairy is not much more dangerous than any other raw food. So don’t be afraid to try it, and see what works for your body and your family.
natschultzsays
“Science” in this country is rigged: The “studies” are all funded and promoted by Big-Ag Special Interests and their allies in Big Government (FDA, CDC, USDA). There has never been an honest, blind study done on the real health benefits of CLEAN raw milk vs. clean pasteurized milk. All the studies done so far have been funded by Big Dairy to make raw milk look bad and pasteurized milk look better than it is. It is not real “science” if you have a pre-determined outcome that you are trying to “prove.”
Fact: Humans EVOLVED drinking RAW MILK. We did not evolve consuming pasteurized anything. A healthy human gut can deal easily with the digestion of a couple of bad pathogens; in fact, our present obsession with antibacterial soaps and vaccines and taking drugs for every little sniffle has weakened modern human immune systems. This has all been brought about by the collusion of Big Government with Big-Ag and Big-Pharma to deliberately make us sick so we have to buy more drugs and fake “cures” from the pharmaceutical industry so they can increase their profits while we humans get sicker and sicker by consuming their Franken-Foods.
来自小的,干净的草饲奶牛场的生牛奶是完全安全健康的。将今天的生牛奶与维多利亚时代纽约的生牛奶相提并论是完全不合法的。维多利亚时代,纽约的街道上满是人和动物的粪便,每个角落都有令人发指的垃圾。是的,如果挤奶女工得了结核病,她就会传染给牛奶。
事实:如果巴氏杀菌奶与病原体接触,那么病原体会通过装有巴氏杀菌奶的容器而不是生牛奶繁殖得更快,因为至少在生牛奶的容器中,病原体必须与所有的有益细菌竞争。
This is why clean raw milk is safer overall – it is kept clean AND COLD from cow to bottling to storage to sale. Big-Ag dairies are not very clean, the processing is not as rigorous because it doesn’t have to be since it all gets combined with milk from numerous other Big-Ag dairies and then batch-pasteurized to kill everything. And then, it gets delivered to the stores and SITS OUT in crates FOR HOURS before it is brought into the stores in the morning. That is why there are two sell-by dates in Metro NY; the NYC date is two days earlier than the surrounding areas because NYC is hotter and dirtier. Weird, since the milk still sits out for hours in the suburbs too.
如果你在沃尔玛或任何其他大商店购买牛奶,那么不,它不应该是生的——它必须经过巴氏消毒。但如果你买的是那种“牛奶”,那么你最好喝椰奶。”
FACT: Clean raw milk safely sours after a few days. It can still be consumed, as long as it does not go moldy (indicates bad bacteria got in it). That is how Clabbered Milk and real Sour Cream are created. If good raw milk starts to taste sour it is fine to drink or even allow to curdle further. I’ve safely consumed it over a week after milking.
Pasteurized milk, on the other-hand, never sours – it ONLY SPOILS. If it smells bad or tastes funny – throw it out regardless of date; it has been contaminated. Be safe and throw it out if it is more than two days past the sell-by date; three days if it has never been unsealed and still looks and smells good.
Low-Temp pasteurized grass-fed milk in glass bottles is the trickiest of all. It spoils really fast; usually before the use-by date. But that is the easiest real milk to purchase near me. But it never sours, it just spoils (off smell) really fast. Even if kept in a 36 degree fridge. That is why I do not believe the “pasteurizing is better” argument.
Any legitimate “study” on raw vs. pasteurized milk would have to compare grass-fed to grass-fed. By default, GRAIN-FED ruminant milk MUST BE PASTEURIZED, since RUMINANTS CANNOT DIGEST GRAINS. Grain-Fed Big-Ag milk is loaded with pathogens before the milk even exits the udders because the guts of those cows are sick from being fed non-digestible feed.