评论
打印
The microwave is a marvelous invention.
微波炉是个了不起的发明。
It's a quick, convenient way to heat up plenty of foods, from frozen dinners to leftover soup.
帮助加热食物，将冰冷的晚餐变成吃剩的汤，微波既快又方便。
But that makes a lot of people question how good it is for you: do microwaves change the nutritional value of food?
但是很多人对微波产生疑惑：微波炉会改变食物的营养价值么？
The short answer is: yes, they do. But so does any other method of cooking.
简单的回答你：会。但是任何烹饪方法都会。
And actually, cooking food in the microwave gets rid of less of some nutrients than other methods like baking or boiling.
事实上，相比煎烤和沸煮这样的方式，用微波炉加热食物所流失的营养更少。
When you preheat an oven, coils of wires heat up and then transfer that energy to air molecules so they're moving around more.
当你预热烤箱时，线卷开始加热，然后将能量转移至空气分子中，因此它们可以更好地环绕。
That motion is heat energy. And when you stick a frozen pizza in, the air molecules bump into the food and transfer heat from the outside in.
这种运动产生热能。当你将冷冻披萨放进去，空气分子碰撞上食物，并将热量由外往内输入。
Microwaves, on the other hand, cook food using electromagnetic radiation. The waves are changing electric and magnetic fields.
另一方面，微波炉利用电磁辐射烹饪食物。微波改变电场和磁场。
So they especially affect molecules like water that are polar, with different charges on different parts.
所以它们尤其对水这样的分子有影响，这种分子有两极，不同部分带有不同的电荷。
When you're microwaving your leftovers, the polar molecules keep flipping around to line up with the changing fields, and heat up.
当你用微波炉加热剩菜剩饭时，有极分子在周围不停跳动与不断改变的磁场电场相对齐加热。
The microwaves go through your whole burrito, so the center reheats at basically the same time as the outside.
微波透过你的整个玉米煎饼，所以食物里外几乎同时加热。
But the air doesn't really change during the microwaving process, because those molecules are mostly nonpolar.
但是在微波过程中，空气并没有真的改变，因为那些分子大部分都是无极性的。
When people are worried about the nutrients in their food, they could mean all kinds of things.
当人们担心食物营养时，这种营养可能是多方面的。
There are carbohydrates and proteins, or stuff like vitamins, compounds that we have to eat,
比如糖类和蛋白质，或者像是维生素之类的人体必需的物质，
because our bodies can't make them independently.
因为我们的身体无法靠自己产生这些物质。
All of those chemicals change when they're microwaved.
所有那些化学物质都在被微波的时候发生了改变。
But they don't change much differently than they would with other cooking methods.
但是相比其他烹饪方法，这种改变并不大。
For example, heat can change proteins in a way that makes them easier to digest.
例如，加热可以改变蛋白质，让人体更好吸收。
There are some differences, though. Like, microwaves can heat up things much faster than other appliances.
虽然仍有些差异。比如，微波炉的加热比其他电器更快。
That matters for the vitamins in your food, which break down more the longer they're exposed to heat.
这就对食物中的维生素有所影响了，加热的时间越长，维生素被分解的越多。
Vitamin C, for one, is particularly sensitive to heat.
维生素C对热度更为敏感。
So a faster cooking time means that more of it sticks around.
所以加热速度越快，保留的维生素越多。
Some vitamins also tend to dissolve in water, so if you're boiling your veggies, those vitamins get pulled into the liquid.
一些维生素易于在水中溶解，所以如果你水煮蔬菜，那些维生素就会流散至水中。
But microwaves avoid that problem too.
但是微波炉能够避免这些问题。
A group of researchers in China took a closer look at cooking broccoli in different ways,
中国一组研究人员近距离地观察了以不同方式烹饪的西兰花，
and measured its vitamin C content, along with some other nutrients. They reported the results in 2009.
并测量了其中的VC含量，以及其他一些营养素。他们在2009年报告了此次结果。
Boiling the broccoli led to the loss of 33 percent of its vitamin C.
水煮西兰花会导致33%VC的流失。
Stir-frying took away 24 percent, while microwaving only led to a loss of 16 percent.
炒西蓝花带走24%的VC，而微波仅导致16%VC的流失。
Steaming was actually the most efficient method, and hardly any of the vitamin C went away.
蒸是最有效的方法，几乎不流失任何VC。
But the microwave was in second place and not too shabby.
但是微波排第二。
So arguably the most convenient cooking tool in your kitchen is also one of the best ways to keep at least some of the vitamins locked in your food.
所以大概最方便的烹饪工具也就是锁住食物营养最好的方法。
And it makes popcorn, too!
爆米花也是一样！
Thanks for watching this episode of SciShow, and special thanks to Joanne K, who's one of our patrons on Patreon, for asking!
感谢收看本期《科学秀》，特别感谢我们的赞助人Joanne K的提问！
If you'd like to ask a question, join us for our monthly Google Hangouts,
如果你想提问，加入我们每月一次的谷歌视频聚会，
or just help us keep posting science videos 7 days a week, you can go to patreon.com/scishow.
或者帮助我们继续制作每周一期的节目，请登录patreon.com/scishow。
