脫脂奶是怎樣脫脂的?

製造商一般是用離心方法將牛奶中的脂肪取出的；因牛奶中所含的乳脂比重較輕，會上浮在牛奶表層，用離心方法就可以取走脂肪了。

還有一個折衷的方法：自己製作低脂牛奶。將牛奶放進微波爐裡加熱，冷卻之後會形成一層表皮，那就是脂肪，將它去除就可以減少一部分脂肪。只要反覆進行這個步驟，基本上牛奶的脂肪含量就不會太多了。如此一來，就能夠控制牛奶的脂肪含量，夏天就不用擔心敷完臉會長痘痘了！

The average composition of milk is 87.2% water, 3.7% fat, 3.5% protein, 4.9% lactose and .7% ash. These percentages vary with the breed of the cow and what is fed to the cow.Skim milk, 2% and 1% milk are made by taking a percentage of the cream from the milk. The cream contains the fat solids in milk. The separated cream is then used to make butter or cheese.Raw milk is collected from cows at the farm, then pumped into calibrated, refrigerated, stainless-steel tanks. The milk is then pumped into the tanker trucks and shipped to a processing plant. Once at the processing plant, the milk is either separated or clarified. Cream, with its heavier fat content, settles to the bottom of storage tanks if the milk is allowed to sit for a short period of time.
Once the separation occurs, a machine simply pushes, or skims, the lower-fat milk off the top. This is how skim milk gets its name. The lighter 1% and 2% milks are made in the same manner, by skimming lower-fat milk off the top. Additional steps separate the milk and fats to reach the targeted fat percentage.