甭管是用来煎蛋 烤土豆 爆爆米花 或是直接抹在吐司片上
Whether you use it to fry your eggs, melt and bake potatoes, use on popcorn
or simply spread on toast. Chances are butter has been part of your life and diet.
Or is it margarine? What is the difference between butter and margarine and is one
healthier than the other? Butter, made from cream or milk has been used for
thousands of years. But scientists eventually took notice of its high
levels of saturated fat. With more than 35 calories per teaspoon, butter
微观黄油的分子结构 我们发现其中含有碳 氢 氧 这三种构成生命体的基本元素
is fattening. When we look at the molecules of butter we see some of the
building blocks of life, carbon, hydrogen and oxygen. But these carbon atoms are
completely surrounded by the hydrogen atoms. And this saturation level
quickly became associated with, and commonly believed to contribute to
cardiovascular disease. Margarine on the other hand is created primarily from
plant oils which have a similar but different chemical composition. The
植物油脂中的碳原子间以双键结合 这样一来 结附其上的氢原子便会变少
carbons double bond with each other so that fewer hydrogen can fit and we call
this unsaturated fat. So far so good, a similar tasting substitute with less
拿来替代黄油 口感相似饱和脂肪却更少 看起来还不错 对吧？
saturated fat. Right?
等等 先别急 不饱和脂肪的熔点较低 因此它的自然状态不是特别稳定
Not so fast, unsaturated fat has a lower melting point and so its natural state
is less solid, like vegetable oil.
In order to get the consistency of butter scientists decided to make it a
little more saturated.
可是 问题来了 为了使人造奶油更稠 在加工的过程中运用到了一种叫做氢化的工艺
The problem is through this process called hydrogenation where more
hydrogen is added and the oil becomes more solid, high temperatures are used
which cause some troublesome changes.
You see, most of these double bonds are in a configuration known as ‘cis bonds’,
可是 氢化过程会让这些顺式键发生翻转 这就产生了所谓的反式结构
but hydrogenation often flips them into something called a ‘trans configuration’.
Ah, the dawn of trans fats.
And while it may seem trivial, this simple yet unwitting flip from ‘cis’ to
leads to significant changes in the way our body processes and metabolizes the
本质上 反式脂肪减少了对人体有益的胆固醇 却增大了对人体有害的胆固醇
molecules. Essentially trans fats lower good cholesterol and higher the bad
cholesterol which increases the risk of coronary heart disease. So while margarine was
你看 人造奶油本来是个更健康的选择 可是现在它的威胁却开始慢慢出现了
initially seen as a healthier option, it’s own hazards slowly came to light.
事实上 现在有很多人造奶油公司都声称自己的产品不含反式脂肪 有些公司的产品却含有反式脂肪
But the truth is that many margarine companies claim to be trans fat-free
nowadays, and some are. At the end of the day if we compare them side by side
你会发现它们各有优劣 黄油完全天然 仅用牛奶便可生产
there are pros and cons for each. Butter is completely natural and typically made
from one ingredient, whereas margarine is processed and has many ingrediants. Butter
黄油富含人体所必需的维生素和矿物质 比如 维生素A和E
also has some essential vitamins and minerals such as vitamin a and e. But margarines
now vary so much it is difficult to make an accurate comparison. Many hard
stick margarines are still high in trans fats and much worse than butter. But some
newer margarines are much lower in saturated fat, lower their calorie count and
contain zero trans fats. The bottom line is to be aware of what you are eating.
Margarine can vary so drastically that looking at the label to understand what
is or isn’t and it will help you make informed decisions.
And there are healthier alternatives to both,
such as vegetable oil spreads or using olive oil to dip your bread instead
of buttering up.
No matter what you choose, the recommended goal is to limit the intake
of saturated fat and avoid trans fats altogether.
This episode of AsapSCIENCE is supported by audible.com, a leading provider of
audiobooks with over one hundred thousand downloadable titles across all
types of literature. If you would like to learn more about food science
想要了解更多有关食品科学的细节 我诚意向你推荐Robert Wolke所著的《爱因斯坦对他的厨子说了什么》这本书
I recommend the book ‘What Einstein Told His Cook’ by Robert Wolke.
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甭管是用来煎蛋 烤土豆 爆爆米花 或是直接抹在吐司片上