乔·罗宾逊,，美国著名营养学家，纽约时报营养膳食类书籍畅销作者，在其《完美牧场》 （《Pasture Perfect》）中揭露了青草散养牛奶相较工厂牛奶的众多营养优势。
在本书里，乔·罗宾逊通过对乳业工厂和青草散养放牧的对比，发现牛奶中有助于抗击癌症的CLA（共轭亚油酸）含量和有利于预防各类疾病的EFAs-omega（脂肪酸）比例在这两种模式下有很大的差距，通过各类研究，她全面概述了选择青草散养乳品的益处以及揭示了散养+草饲对于生产健康乳制品的绝对前提性。因为事实上，美国85%-95%的奶牛吃的都不是草，而是粮食作物等混合饲料；呆的不是青草遍野的牧场，而是积满了各种脏污和饲料混合物的水泥地面。那么，究竟现代乳业工厂里奶牛与传统青草散养奶牛产出的牛奶差距有多大呢？
首先，两种模式下牛奶的CLA（共轭亚油酸）含量差距很大。所谓CLA（共轭亚油酸），其实是一种脂肪，它在我们的身体里起到一个最有效的癌症战士的作用。青草散养的奶牛产出的牛奶CLA含量高出奶牛工厂的5倍之多。法国研究人员曾做过360名女性乳房组织的CLA含量水平对比，结果表明，乳房组织中CLA含量最高的女性比CLA含量最低的女性少74%患乳腺癌的几率，可见CLA含量对于防癌、抗癌有着举足轻重的作用。
其次，牛奶中存在的两种脂肪酸（EFAs-omega-6、EFAs-omega-3）比例不同。大量研究表明，如果这两种脂肪酸在饮食中的比例达到1:1，那么患癌症、心血管疾病、自身免疫性疾病、过敏、肥胖、糖尿病、老年痴呆症以及其他精神疾病的风险将会大大降低。然，并非所有的牛奶都拥有脂肪酸两者间的最佳比例。（见下图：绿条代表EFAs-omega-3脂肪酸，黄条代表EFAs-omega-6脂肪酸）
显而易见，只有青草散养的奶牛产出的牛奶才能达到两种脂肪酸间的最佳比例，而其他不同程度用饲料来取代青草都会造成牛奶中两种脂肪酸间的不平衡，导致牛奶营养的缺失。而在日常生活中，我们在超市购买的牛奶可能更糟糕，因为有些奶牛根本吃不到青草，这也为我们的健康埋下了隐患。
另外，青草散养的奶牛因为食用新鲜牧草而不是饲料，因而产出的牛奶中β-胡萝卜素、维生素A和维生素E含量比奶牛工厂里奶牛产出的牛奶要高得多。
而现代化乳业之所以选择将奶牛圈禁在工厂里和用粮食谷物而非青草来喂养它们，只是因为在这样的条件下，奶牛能比青草散养条件下的奶牛产出更多的牛奶。在牛奶工厂里，通常的做法是对奶牛进行每两周一次的激素注射，同时，奶牛一天要挤三次奶，而不是两次。在这样的产奶机制里，奶牛工厂里的奶牛产量是散养环境下的三倍之多。
如今我们仍然能在澳洲见证乔·罗宾逊笔下的“完美牧场”，四季常绿的草场为奶牛提供了新鲜的牧草，广袤无垠的草地上，奶牛们肆意奔跑。放牧原生=草饲+散养，这种源自澳洲的放牧模式，在今天已经难能可贵，康多瑞深谙草饲、散养对优质乳品的好处，因而我们只选散养程度高，坚持青草喂养的牧场作为奶源地，生产最优质的乳品。
以上数据均选自此文献:
另附《完美牧场》英文节选
Super Natural Milk
By Jo Robinson
Most cartons of milk in the supermarket show a picture of cows contentedly grazing on grass. In reality, 85 to 95 percent of the cows in the United States are now being raised in confinement, not on pasture. The grass they eat comes in the form of hay, and the ground that they stand on is a blend of dirt and manure.
The reason for confining cows in feedlots and feeding them grain rather than grass is that they produce far more milk under these unnatural conditions. If you also inject them with bi-weekly hormones, standard practice in the dairy industry, they produce even more. Milk them three times a day instead of two and you have the tried and true formula for today’s Super Producers. On average, cows raised in confinement produce more than three times as much milk as the family cow of days gone by and 15 times the amount required to raise a healthy calf.
But with so much emphasis on quantity, the nutritional content of our milk has suffered. One of the biggest losses has been in its CLA content. CLA, or "conjugated linoleic acid," is a type of fat that may prove to be one of our most potent cancer fighters. Milk from a pastured cow has up to five times more CLA than milk from a grain-fed cow. To date, most of the proof of the health benefits of CLA has come from test tube or animal studies. But a few human studies have produced encouraging results. For example, French researchers compared CLA levels in the breast tissues of 360 women. The women with the most CLA in their tissue (and thus the most CLA in their diets) had a 74 percent lower risk of breast cancer than the women with the least CLA [1]. If an American woman were to switch from grain-fed to grass-fed dairy products, she would have CLA levels similar to the women in the study who had the lowest rate of cancer.
Milk from pastured cows also contains an ideal ratio of essential fatty acids or EFAs. There are two families of EFAs—omega-6 and omega-3 fatty acids. Studies suggest that if your diet contains roughly equal amounts of these two fats, you will have a lower risk of cancer, cardiovascular disease, autoimmune disorders, allergies, obesity, diabetes, dementia, and various other mental disorders.[2]
Take a few moments to study the chart below showing EFA levels in milk from cows fed varying amounts of grass and grain.[3] The green bars represent omega-3 fatty acids, and the yellow bars represent omega-6 fatty acids. As you can see, when a cow is raised on pasture (represented by the two bars on the far left), her milk has an ideal, one-to-one ratio of EFAs.
Take away one-third of the grass and replace it with grain or other supplements (represented by the two bars in the middle) and the omega-3 content of the milk goes down while the omega-6 content goes up, upsetting an essential balance.
Replace two-thirds of the pasture with a grain-based diet (illustrated by the two bars on the far right) and the milk has a very top-heavy ratio of omega-6 to omega-3 fatty acids. This ratio has been linked with an increased risk of a wide variety of conditions, including obesity, diabetes, depression, and cancer. Much of the milk you buy in the supermarket has an even more lopsided ratio than this because the cows never graze on pasture.
Milk from pastured cows offers additional health benefits. (I'm beginning to sound like a TV infomercial: "But wait! There's more!") Besides giving you five times more CLA and an ideal balance of EFAs, grass-fed milk is higher in beta-carotene, vitamin A, and vitamin E. This vitamin bonus comes, in part, from the fact that fresh pasture has more of these nutrients than grain or hay. (When grass is dried and turned into hay, it loses a significant amount of its vitamin content.) These extra helpings of vitamins are then transferred to the cow's milk.
There's another factor as well. As I mentioned, a cow raised on pasture produces far less milk than a cow raised in a confinement dairy on a grain-based diet. This is a bane for the farmer but a blessing for the consumer. The less milk a cow produces, the more vitamins in her milk.[4] This is because a cow has a set amount of vitamins to transfer to her milk, and if she's bred, fed, and injected to be a Super Producer, her milk has fewer vitamins per glass. It's a watered down version of the real thing.
Oh, I almost forgot the best part of all. Dairy products from grass-fed cows taste delicious, and they have a rich yellow color that is visible proof of their bonus supply of carotenes. Serve cheese or butter from a grass-based dairy, and everyone will notice the difference. Also, your cookies and cakes will have that rich buttery color that hasn't been seen since Great-Grandma's day. (You do bake, don't you?)
So where can you find milk from pastured cows? All of the dairies listed onwww.eatwild.com keep their cows outdoors on grass whenever possible. Some farmers supplement their cows with small amounts of grain; if so, their listing will detail the type and amount. To find your local producer, go to our list of grass-fed suppliers and click on your state. We also have a special section devoted to farmers who feed their cows 100 percent forage-based diets.
Expect to pay more for this high-quality milk from humanely treated cows. The main reason is the low volume of milk per cow. In order to make a living, pasture-based dairy farmers must get a premium price for their premium milk.
Got grass-fed milk?
Jo Robinson is a New York Times bestselling writer. She is the author or coauthor of 11 nationally published books including Pasture Perfect, a comprehensive overview of the benefits of choosing products from pasture-raised animals, and The Omega Diet (with Dr. Artemis Simopoulos) the healthiest diet of all Mediterranean diets . To order Jo’s books or learn more about grass-fed products, visit http://eatwild.com.
[1]Bougnoux ,et al.,Inform, 10:S43, 1999.
[2] For more information about essential fatty acid balance, read The Omega Diet. The book provides 24 pages of pertinent scientific references.
[3] The data comes from: Dhiman, T. R., G. R. Anand, et al. (1999). "Conjugated linoleic acid content of milk from cows fed different diets." J Dairy Sci 82(10): 2146-56.
[4] Jensen, S. K., A. K. Johannsen, et al. (1999). "Quantitative secretion and maximal secretion capacity of retinol, beta-carotene and alpha-tocopherol into cows' milk." J Dairy Res 66(4): 511-22.
