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  • Olive oil is 100% fat;

    橄欖油百分之百是脂肪;

  • there's nothing else in it.

    甚麼其他的成分都沒有

  • Pancake mix, on the other hand, is only about 11% fat.

    反觀鬆餅粉,只有百分之 11 的油脂

  • And, yet, olive oil is good for you,

    但是橄欖油卻對你比較好,

  • and pancake mix is not.

    鬆餅粉則不好

  • Why is that?

    為什麼呢?

  • As it turns out, the amount of fat we eat doesn't impact our weight or our cholesterol or our risk of heart disease nearly as much as what kind of fat we eat.

    事實證明,我們吃下去的油脂含量並不會影響我們的體重,或是我們的膽固醇,或是我們得到心臟病的機率。我們吃下的油脂種類才會

  • But let's back up:

    讓我們看一些背景知識:

  • What is fat?

    甚麼是脂肪 (油脂)?

  • If we were to zoom in on a salmon,

    如果我們用鮭魚來當例子,

  • which is a fatty fish,

    鮭魚是種很肥的魚,

  • past the organs,

    穿過器官,

  • past the tissues,

    穿過組織,

  • into the cells,

    進入細胞裡,

  • we would see that the stuff we call fat

    我們就可以看到所謂的脂肪

  • is actually made up of molecules called triglycerides,

    事實上是由被稱作三酸甘油酯的分子所組成,

  • and they are not all alike.

    而它們是不一樣的

  • Here's one example.

    這兒有個例子

  • Those three carbons on the left, that's glycerol.

    左邊這三個碳 (C),那是甘油 (丙三醇)

  • Now, you can think of that as the backbone

    你可以把他想成一條骨幹

  • that holds the rest of the molecule together.

    支撐著其餘所有的分子

  • The three long chains on the right

    右邊三條長鏈

  • are called fatty acids,

    叫做脂肪酸,

  • and it's subtle differences in the structures of these chains

    而它在這些長鏈中細微的不同

  • that determine whether a fat is,

    決定了脂肪的定義,

  • let's say, solid or liquid;

    比如說,它呈固體或液體

  • whether or not it goes rancid quickly;

    它腐敗的速度多快

  • and, most importantly, how good or how bad it is for you.

    還有最重要的,它對健康是否有益

  • Let's take a look at some of these differences.

    讓我們來看看這些差別

  • One is length.

    其一是長度

  • Fatty acids can be short or long.

    脂肪酸或長或短

  • Another, more important difference

    還有一個更重要的差別

  • is the type of bond between the carbon atoms.

    是碳原子相連的方式

  • Some fatty acids have only single bonds.

    有些脂肪酸只有單鍵

  • Others have both single and double bonds.

    其他的有單鍵和雙鍵

  • Fatty acids with only single bonds

    只有單鍵的脂肪酸

  • are called saturated,

    叫飽和脂肪,

  • and those with one or more double bonds

    而那些有單鍵和雙鍵的

  • are called unsaturated.

    則叫做未飽和脂肪

  • Now, most unsaturated fats are good for you, while saturated fats are bad for you in excess.

    大多數的未飽和脂肪酸對你都是有益的,而過度的飽和脂肪酸對你不好

  • For saturated fats, the story pretty much ends there

    飽和脂肪酸該講得差不多都講完了

  • but not for unsaturated fats.

    但是未飽和脂肪酸則更複雜一些

  • The double bonds in these molecules have a kind of weird property; they're rigid.

    這些分子中的雙鍵有種很奇怪的性質;他們很死板

  • So, that means there are two ways

    所以這表示有兩種方式

  • to arrange every double bond.

    來安排每一組雙鍵連結

  • The first is like this,

    第一種組合像這樣,

  • where both hydrogens are on same side

    兩個氫原子在同一邊

  • and both carbons are on the same side.

    而兩個碳離子在同一邊

  • The second way is like this.

    第二種組合像這樣

  • Now the hydrogens and carbons

    氫原子和碳原子

  • are on opposite sides of the double bond.

    分別在雙鏈的兩端

  • Now, even though both of these molecules

    雖然這兩組分子

  • are made up of exactly the same building blocks,

    是由完全相同的模塊組成,

  • they are two completely different substances,

    他們的內容卻大不相同,

  • and they behave completely differently inside of us.

    而且它們在我們身體裡面起的反應也截然不同

  • The configuration on the left is called CIS,

    左邊這個配置結構叫做 CIS,

  • which you've probably never heard of.

    你可能從來沒聽過

  • The one of the right is called TRANS,

    右邊這個叫做 TRANS,

  • and you probably have heard of trans fats before.

    是比較常聽到的反式脂肪

  • They don't go rancid,

    但是他們不會腐敗,

  • they're more stable during deep frying,

    他們在油炸的過程中比較穩定,

  • and they can change the texture of foods

    還可以改變食物的組成

  • in ways that other fats just can't.

    這是其他油脂無法做到的

  • They're also terrible for your health,

    可是對你的健康有害,

  • by far worse than saturated fat,

    甚至比飽和脂肪還要大得多,

  • even though technically they're a type

    雖然他們可以稱得上是同類

  • of unsaturated fat.

    的不飽和脂肪

  • Now, I know that seems crazy,

    好了,我知道這聽起來很瘋狂,

  • but your body doesn't care

    但你的身體才不管

  • what a molecule looks like on paper.

    這些分子被寫成化學式長甚麼樣子。

  • All that matters is the 3-D shape

    他們只在乎 3D 的形狀

  • where the molecule fits,

    分子能被放在哪裡,

  • where it doesn't,

    不能被放在哪裡,

  • and what pathways it interferes with.

    它會干擾甚麼路徑

  • So, how do you know if a food has trans fat in it?

    你要怎麼知道食物裡有沒有反式脂肪?

  • Well, the only sure way to know

    唯一能確定的方式

  • is if you see the words,

    是你看到成分表上寫著

  • "partially hydrogenated" in the ingredients list.

    「部分氫化」

  • Don't let nutrition labels or advertising fool you.

    別被營養標示或是廣告詞愚弄

  • The FDA allows manufacturers to claim

    FDA 允許製造商宣稱

  • that their products contain

    他們的產品

  • "0" grams of trans fat

    完全不含反式脂肪

  • even if they actually have up to half a gram per serving.

    就算它們每一份食物都含了 0.5 克

  • But there are no hard and fast rules

    但至於每一份食物究竟是多少

  • about how small a serving can be,

    並沒有明確地規定

  • and, that means, you'll have to rely on seeing those key words,

    而且那表示你必須依靠關鍵字:

  • partially hydrogenated,

    「部分氫化」

  • because that's how trans fats are made,

    因為反式脂肪就是這樣製造出來的,

  • by partially hydrogenating unsaturated fats.

    由部分氫化的未飽和脂肪

  • So, let's go back to our olive oil and pancake mix from before.

    所以讓我們回到橄欖油跟鬆餅粉的討論中

  • Olive oil is 100% fat.

    橄欖油百分之百是脂肪

  • Pancake mix is only 11% fat.

    鬆餅粉只有百分之 11

  • But olive oil is mostly unsaturated fat,

    但是橄欖油大多分是未飽和脂肪,

  • and it has no trans fat at all.

    不含任何反式脂肪

  • On the other hand, more than half the fat

    反觀有過半的脂肪

  • in pancake mix is either saturated or trans fat.

    在鬆餅粉中是飽和脂肪或者反式脂肪

  • And, so, even though olive oil has 10 times

    所以雖然橄欖油的油脂含量

  • as much fat as pancake mix,

    是鬆餅粉的十倍,

  • it's healthy for you,

    它卻是健康的,

  • whereas pancake mix is not.

    鬆餅粉卻不是

  • Now, I'm not trying to pick on pancake mix.

    我並沒有刻意要找鬆餅粉的碴

  • There are lots of foods

    有很多種食物

  • with this type of fat profile.

    都帶有這種油脂

  • The point is this:

    總歸來說,

  • It's not how much fat you eat,

    並不是你吃了多少油脂,

  • it's what kind of fat.

    而是你吃了哪一種油脂

  • And what makes a particular fat healthy or unhealthy

    才是促成特定脂肪健康或是不健康的關鍵

  • is its shape.

    是它的組成方式

Olive oil is 100% fat;

橄欖油百分之百是脂肪;

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B2 中高級 中文 美國腔 TED-Ed 脂肪 脂肪酸 橄欖油 分子 健康

【TED-Ed】 什麼是脂肪?(What is fat? - George Zaidan)

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    drsueec 發佈於 2016 年 03 月 09 日
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