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最新相关问题巴氏奶（冷鲜奶）和UHT奶（常温奶），你能尝出区别吗？ - 知乎专栏
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不过，脂肪液滴的集聚发生在喝奶之前，当然能带来一番美味，但如果发生在运输或者贮存当中，那就是悲剧了。所以对于厂商来说，脂肪液滴的集聚应该是一件需要避免的事情，而方法呢也很简单粗暴，借助均质机的剪切力和压力使牛乳高速通过狭缝，在湍流与气穴的联合作用下打碎乳中的脂肪球，使脂肪球的平均直径变小，从而避免了它们的过度集聚——这就是所谓的均质化。更小的脂肪液滴使得牛奶的口感更加浓厚，但同时也无法通过短时间的加热得到美味的“奶皮”了。不同于鲫鱼汤、骨头汤中的脂肪液滴，乳汁中脂肪液滴的来历可大不简单。它们最初是在乳腺小泡分泌细胞的内质网上产生的，主要成分是甘油三酯。在细胞中，这些由单层磷脂包裹的脂肪液滴互相碰撞、融合，一边长大，一边向细胞膜移动。它们会和细胞膜接触，并被细胞膜渐渐包裹起来，最后通过分泌泡的形式进入到乳汁当中。它还有个高大上的名字叫“乳脂球”，而包被乳脂球的膜则直接来源于乳腺分泌细胞的细胞膜——所以喝牛奶在某种程度上，也算啃了一口牛乳咪咪了。↑↑↑乳脂球（MFG，milk fat globule）的形成过程这边之所以提到乳脂球膜，是因为DHA大家炒得差不多了，去年似乎炒乳脂球膜概念的配方奶粉渐渐多了起来。首先呢，乳脂球膜的确是个好东西，事实上，乳脂球膜上的磷脂占到了乳汁中总磷脂含量的70%——谁让人家本来就是细胞膜的一部分呢，细胞膜的骨架就是磷脂呀。其次，人乳中神经鞘磷脂的含量比牛乳高了将近一倍，而人脑中神经鞘磷脂又非常多——这就容易让人拍脑袋说：添加了乳脂球膜的配方奶粉是不是会有助于提高智力呢？其实除了2012年有一项来自印尼的研究外，还没有其它公开发表的证据证明这一点。最后要黑一把脱脂奶。乳脂肪的分解是呈味物质产生的重要途径，而许多呈味物质，也需溶于乳脂肪才能存留在牛奶中。所以如果说巴氏奶和常温奶的口味见仁见智，但是脱脂奶难喝应该是公认的。比如二甲基硫醚（DMS），上次我们说到它是牛奶最特征的风味物质。不巧的是它难溶于水，于是在脱脂奶当中无论如何也不会有牛奶这番最原初的风味了。 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