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It's so obvious that it's practically proverbial. You can't unboil an egg.
很明显又众所周知的是。你不能把一个熟蛋变生。
Well, it turns out you can, sort of.
然而，其实在某种程度上你是可以的。
What thermal energy does to the eggs' molecules, mechanical energy can undo.
热能对蛋的分子所做的事，可以依靠机械能将其还原。
Eggs are mostly made of water and proteins.
蛋主要是由水和蛋白质组成。
The proteins start off folded up into intricate shapes, held together by weak chemical bonds.
蛋白质最开始是折叠成一种复杂的形状，依靠弱的化学键连接在一起。
Adding heat disrupts those bonds, allowing the proteins to unfold, uncoil, unwind and wiggle freely.
加热能分解化学键，使蛋白质能够展开，松绕，分离，变得可以自由摆动。
This process is called denaturing.
这个过程被称为“变性”。
The newly liberated proteins bump up against their neighbors and start to form new bonds with each other,
新解放的蛋白质，会与邻近的相互撞击，并在其中形成新的化学键，
more and more as the heat increases, until finally, they're so entangled that they gel into a solid mass, a boiled egg.
当热量变得越来越多后，最后它们将形成一个固体，这就是煮熟的蛋。
That entanglement might look permanent, but it's not.
这个过程可能看起来不可逆，但其实不是的。
According to a chemical idea called the principle of microscopic reversibility, anything that happens,
根据一个叫做微观可逆原理的化学观点，任何已发生的事情，
like egg proteins seizing up, can theoretically unhappen if you retrace your steps.
比如说鸡蛋中的蛋白质变为固体的情况，如果你倒着做每一步，理论上应该可以将其还原。
But adding more heat will tangle the proteins further, and cooling them down will only freeze them,
但增加更多的热量，只会使蛋白质纠缠的更紧，而冷却只会冻住它们，
so here's the trick: spin them around ridiculously fast.
所以这里的秘诀是：将其极快的旋转。
I'm not kidding. Here's how it works.
我没在开玩笑。以下就是原理。
First, scientists dissolve boiled egg whites in water with a chemical called urea, a small molecule that acts as a lubricant,
首先，科学家将煮熟的蛋白溶解，在水中加以一种名为尿素的化学物质，它是一个小分子，起到润滑剂的作用，
coating the proteins' long strands and making it easier for them to glide past each other.
附着在蛋白质较长的一股，使得它们更容易得滑过对方。
Here's the key part.
接下来是关键的部分。
The solution nearest the wall spins faster than the solution closer to the middle.
离试管壁最近的溶液，要比中间的溶液旋转得更快。
That difference in velocity creates sheer stresses that repeatedly stretch and contract the proteins
这个速度上的区别产生了剪切应力，会重复拉伸和收缩蛋白质，
until eventually they snap back into their native shapes and stay there.
直到最后它们恢复成原始的形状，并稳定下来。
By the time the centrifuge stops spinning, the egg white is back in its original unboiled state.
当离心机停止旋转，鸡蛋白就恢复成了未被煮过的形态。
This technique works with all sorts of proteins.
这项技术适用于所有蛋白质。
Bigger, messier proteins can be more resistant to being pulled apart,
更大和更混乱的蛋白质将会更难还原，
so scientists attach a plastic bead to one end that adds extra stress and encourages it to fold up first.
所以科学家会在蛋白质的一端黏上一个塑料珠，以此来产生额外的重量，并会加大收缩，促使其先折叠。
This unboiling method won't work with a whole egg in its shell
这个方法不适用于一个完整的带壳的蛋，
since the solution has to spread throughout a cylindrical chamber.
因为溶液必须在圆柱体容器内展开。
But the applications go way beyond uncooking your breakfast, anyhow.
但这一实际应用远超出还原你的早餐。
Many pharmaceuticals consist of proteins that are extremely expensive to produce,
很多含有蛋白质的药物的生产费用非常高，
partly because they get stuck in tangled up aggregates,
有些是因为他们卡在了聚集蛋白质中，
just like cooked egg whites and have to be untangled and refolded before they can do their jobs.
就像煮熟的蛋白，这些必须在他们开始工作前被打散和展开。
This spinning technique has the potential to be an easier, cheaper and quicker method than other ways to refold proteins,
这个旋转方法，相比于其他再折叠蛋白质的方式，能成为更简单、便宜、快速的方法。
so it may allow new drugs to be made available to more people faster.
所以，它可能会使新药物的出现变得更加快捷。
And there's one more thing you need to keep in mind before trying to uncook all of your food.
在还原你的食物之前，还有一件事情需要你记住。
Boiling an egg is actually an unusual cooking process
煮蛋实际上是个不寻常的过程，
because even though it changes the way proteins are shaped and bound together,
因为即使它使蛋白质的形状和连接方式发生了改变，
it doesn't actually change their chemical identity.
但它的化学性质并没有改变。
Most types of cooking are more like the famous Maillard reaction, which makes chemical changes
大多数烹饪过程类似着名的“梅拉德反应”，就是会发生化学变化，
that turn sugars and proteins into delicious caramel crunchiness and are a lot harder to undo.
将糖分和蛋白质转换成美味的焦糖脆，这会非常难还原。
So you might be able to unboil your egg, but I'm sorry to say you can't unfry it...yet.
所以，你可以还原你的煮蛋，但很抱歉，到目前为止，你还不能还原你的煎蛋。
