Why is ketchup so hard to pour? - George Zaidan

为什么番茄酱这么难挤？

翻译人员: Carrie Li 校对人员: Jia (Jolie) YU

French fries are delicious.

我们都知道炸薯条很好吃

French fries with ketchup are a little slice of heaven.

再配上番茄酱简直就是人间美味

The problem is it's basically impossible

但问题是

挤出刚刚好的量的番茄酱实在是太难了

to pour the exactly right amount.

We're so used to pouring ketchup that we don't realize

我们平时经常挤番茄酱

how weird its behavior is.

但是从来没注意到过番茄酱有多么的奇怪

Imagine a ketchup bottle filled with a straight up solid like steel.

想像你的番茄酱瓶里装的是固体，比如不锈钢

No amount of shaking would ever get the steel out.

不管你怎么摇晃，不锈钢都不会出来

Now imagine that same bottle full of a liquid like water.

现在再想像一下装了水的番茄酱瓶子

That would pour like a dream.

把水倒出来简直易如反掌

Ketchup, though, can't seem to make up its mind.

但是番茄酱呢，好像很纠结

Is it is a solid? Or a liquid?

它到底是固体？还是液体？

The answer is, it depends.

答案是，看情况。

The world's most common fluids like water, oils and alcohols

这世界上最常见的液体，比如水，油，还有酒精

respond to force linearly.

会对力的作用产生线性反应

If you push on them twice as hard, they move twice as fast.

如果你用两倍的力去挤它们，它们就会以两倍的速度流出来

Sir Isaac Newton, of apple fame, first proposed this relationship,

因为苹果而出名的艾萨克·牛顿先生，首次提出了上述现象

and so those fluids are called Newtonian fluids.

所以它们被称为牛顿流体

Ketchup, though, is part of a merry band of linear rule breakers

番茄酱呢，却是线性规则破坏者小团体中的一员

称为非牛顿流体

called Non-Newtonian fluids.

Mayonnaise, toothpaste, blood, paint, peanut butter

蛋黄酱，牙膏，血液，颜料，花生酱

and lots of other fluids respond to force non-linearly.

还有其他很多流体，都不会对力的作用产生线性反应

That is, their apparent thickness changes

也就是说，它们的浓度

depending on how hard you push, or how long, or how fast.

会根据你的用力大小，时间长度和用力速度改变

And ketchup is actually Non-Newtonian in two different ways.

事实上，番茄酱会表现出两种非牛顿流体现象

Way number one: the harder you push, the thinner ketchup seems to get.

现象一：你越用力挤，番茄酱越稀

Below a certain pushing force,

但是如果力道小到特定的程度，

ketchup basically behaves like a solid.

番茄酱看起来就像固体一样了

But once you pass that breaking point,

但是一旦你超过了那个临界点

it switches gears and becomes a thousand times thinner than it was before.

它就摇身一变，变得比刚才稀很多

Sound familiar right?

听起来很耳熟吧？

Way number two: if you push with a force below the threshold force

现象二：如果你的力道没有达到临界点，

eventually, the ketchup will start to flow.

番茄酱最后还是会流出来的

In this case, time, not force, is the key to releasing ketchup

这种情况下，作用时间长度，而不是力

才是挤出番茄酱的关键

from its glassy prison.

Alright, so, why does ketchup act all weird?

好吧，那番茄酱到底为什么这么与众不同呢？

Well, it's made from tomatoes, pulverized, smashed, thrashed,

嗯，首先，它是番茄做的。

番茄经过各种切碎，挤压，搅拌之后变得面目全非

utterly destroyed tomatoes.

See these tiny particles?

看到这些小颗粒了吗？

This is what remains of tomatoes cells

它们是在番茄被各种处理后

after they go through the ketchup treatment.

残留下来的番茄细胞

And the liquid around those particles?

那么这些小颗粒周围的液体呢？

That's mostly water and some vinegar, sugar, and spices.

大部分都是水，还有一些醋，糖，以及香料

When ketchup is just sitting around,

当番茄酱静止的时候

the tomato particles are evenly and randomly distributed.

番茄颗粒都很均匀的分布其中

Now, let's say you apply a weak force very quickly.

现在，假如你突然用很小的力挤番茄酱

The particles bump into each other,

这些小颗粒就会冲到一起

but can't get out of each other's way,

堵在一起，谁都不让谁

so the ketchup doesn't flow.

当然就不会流动啦

Now, let's say you apply a strong force very quickly.

那如果你突然用很大力去挤番茄酱呢？

That extra force is enough to squish the tomato particles,

力度大到可以把颗粒压扁

so maybe instead of little spheres,

它们不再是球型

they get smushed into little ellipses, and boom!

而是变成了椭圆体，

Now you have enough space for one group of particles

于是乎，现在就有空间让一部分小颗粒穿过去

to get passed others and the ketchup flows.

番茄酱就开始流动了

Now let's say you apply a very weak force but for a very long time.

再假如你用很小的力挤番茄酱，持续一段时间后

Turns out, we're not exactly sure what happens in this scenario.

但是，嗯，我们也不是很清楚会怎样

One possibility is that the tomato particles near the walls of the container

有一种可能是，靠近瓶壁的番茄颗粒

会慢慢的移动到瓶子中间去

slowly get bumped towards the middle,

leaving the soup they were dissolved in,

剩下只有液体

which remember is basically water,

基本上就是水

near the edges.

留在边缘

That water serves as a lubricant betwen the glass bottle

于是水就会变成

瓶壁和番茄酱之间的润滑剂

and the center plug of ketchup,

and so the ketchup flows.

番茄酱就出来了

Another possibility is that the particles slowly rearrange themselves

另一种可能就是小颗粒重新组合

into lots of small groups, which then flow past each other.

形成一个个小团儿，然后再慢慢移动

Scientists who study fluid flows are still actively researching

研究流体运动的科学家们还在探索

how ketchup and its merry friends work.

到底番茄酱之类的东西是怎么回事

Ketchup basically gets thinner the harder you push,

番茄酱呢，你越用力，它们就会变得越稀

but other substances, like oobleck or some natural peanut butters,

但是其他物体呢，比如欧波力客或者花生酱

actually get thicker the harder you push.

你越用力它们反倒变得越稠

Others can climb up rotating rods,

还有一些能顺着转动的棍棒向上流动的

or continue to pour themselves out of a beeker,

还有一些，一旦你开始倾倒，

once you get them started.

它们就能一直不停的倾泻。

From a physics perspective, though,

从物理学的角度来讲

ketchup is one of the more complicated mixtures out there.

番茄酱是世界上少数几个最复杂的混合物之一

And as if that weren't enough, the balance of ingredients

如果这还不够的话，

平衡的成分，再加上广泛运用于水果饮料和奶昔的

and the presence of natural thickeners like xanthan gum,

天然增稠剂黄原胶的作用下，

which is also found in many fruit drinks and milkshakes,

can mean that two different ketchups

能够证明两种不同的番茄酱

can behave completely differently.

会有截然不同的表现

But most will show two telltale properties:

但是一般会出现两种迹象

sudden thinning at a threshold force,

在临界强度压力下突然变稀

and more gradual thinning after a small force

或者在持续的轻缓挤压下

is applied for a long time.

慢慢变得稀薄

And that means you could get ketchup out of the bottle in two ways:

也就是说你有两种方法可以把番茄酱挤出来

either give it a series of long, slow languid shakes

要么就是缓缓的慢慢的摇晃

making sure you don't ever stop applying force,

注意不要停止用力

or you could hit the bottle once very, very hard.

或者你可以对着瓶底猛地一击

What the real pros do is keep the lid on,

一般内行会先不打开瓶盖

give the bottle a few short, sharp shakes

快速的晃动几下瓶子

to wake up all those tomato particles,

把里面的小番茄颗粒摇醒

and then take the lid off

然后拧开瓶盖

and do a nice controlled pour onto their heavenly fries.

就可以将番茄酱自如的挤到美味的薯条上啦