Are spotty fruits and vegetables safe to eat

有斑點(diǎn)的水果和蔬菜可以安全食用嗎

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In 2010, $30?billion worth of fruits and vegetables

were wasted by American retailers and shoppers

in part because of cosmetic problems and perceived spoilage.

That's a poor use of about 30% of the produce on the market,

not to mention the water and energy required to grow and transport it,

and the landfill space getting used up by rotting fruit.

So what are those cosmetic problems?

2010年，價(jià)值三百億美元的蔬菜水果

被美國的商家和消費(fèi)者白白浪費(fèi)掉，

其中一部分是因?yàn)?品相問題和表面的污損。

這些損失就占到了市場上30%的農(nóng)產(chǎn)品，

更不用說其生長和運(yùn)輸過程中 所耗費(fèi)的水電了，

連垃圾場也不得不 騰出空間來傾置腐爛的水果。

那么品相問題是什么？

You've probably passed over a spotty apple in the grocery store,

or accidentally sunk your thumb into a mushy patch on a tomato.

These blemishes can doom produce to the trash can.

But what are they anyway,

and are they actually bad for you?

你一定在水果店嫌棄過 帶有斑點(diǎn)的蘋果，

或是不小心捏到了番茄上塌軟的部分。

這些污損注定了這樣的農(nóng)產(chǎn)品要被扔掉。

但它們究竟是什么，

對我們真的有害嗎？

Those spots are evidence of an epic battle between plants and microbes.

Like humans, plants coexist with billions of fungi and bacteria.

Some of these microbes are beneficial to the plant,

suppressing disease and helping it extract nutrients.

Others are pathogens, attacking the produce,

still alive as it sits in a store display or your refrigerator

and siphoning off molecules they can use themselves.

The good news is ?they're almost never bad for you.

這些污損實(shí)際上是微生物侵入植物的證據(jù)。

和人類一樣，植物生長的環(huán)境 也存在著數(shù)不盡的真菌和細(xì)菌。

有些是對植物有益的，

比如抑制病蟲害和增強(qiáng)養(yǎng)分吸收。

其它則是病原菌，能夠破壞植株，

即使蔬果被擺上了商品架或者 放入冰箱，它們還有殘留，

繼續(xù)榨取宿主養(yǎng)分以供自己存活。

所幸它們對人體幾乎是無害的。

These fungi and bacteria have spent millions of years

developing strategies to overcome a plant's immune system.

But healthy human immune systems are different enough

that those strategies ?just don't work on us.

So in a plant, what does this process look like?

這些真菌和細(xì)菌已經(jīng)用了 幾百萬年的時(shí)間

進(jìn)化出抵御植物免疫系統(tǒng)的能力。

但是由于健康人體的 免疫系統(tǒng)和植物的大相徑庭，

它們的抗免疫能力對我們不起作用。

那么在植株上， 這一過程是如何發(fā)生的呢？

Microbes can reach plants ?in a number of ways,

like getting splashed onto it during watering or fertilization.

Under the right conditions,

the microbes grow ?into large enough colonies

to attack the waxy outer layer ?of fruit or leaves.

Their target: the delicious sugars and nutrients inside.

This type of pathogen often makes spots like this.

微生物接觸植株的方式很多樣，

比如在澆水施肥的時(shí)候?yàn)⒙涞街仓晟稀?/p>

然后在合適的條件下，

微生物繁殖成大塊菌落，

并開始破壞水果或者葉片的蠟狀表皮。

它們的目標(biāo)是內(nèi)部美味的糖分和養(yǎng)分。

這種病原菌通常會(huì)導(dǎo)致這樣的斑點(diǎn)。

A clump of bacteria drains the nutrients and color from the fruit's cells

making that yellow halo.

It then moves outward,

leaving a black spot of dead cells in its wake.

Each spot, which could contain hundreds of thousands of microbes

is actually caused by a combination of microbial attack

and the host defending itself.

凝塊的細(xì)菌攝取養(yǎng)分 促使水果細(xì)胞發(fā)生了顏色變化，

出現(xiàn)黃色的圓形斑點(diǎn)。

之后它們向外擴(kuò)散，

在待過的地方留下黑斑狀的死細(xì)胞。

一個(gè)斑點(diǎn)里可能有成百上千的微生物，

實(shí)際上這是它們?nèi)肭趾退拗髯孕l(wèi)的過程中

共同造就的產(chǎn)物。

For example, this is the bacterial pathogen Pseudomonas syringae.

Once on a tomato, ?it enters the fruit and leaves,

multiplies in the space between the cells,

and produces toxins and proteins

that allow it to disrupt ?the plant's immune response.

One toxin coronatine makes plants' stomata open up,

allowing bacteria to enter ?more freely.

Coronatine also activates pathways leading to chlorophyll degradation,

which you can see as yellow spots.

As the bacteria continue to feed and multiply,

they start to kill off the plant cells.

That explains spots, but what about mushy blemishes?

舉個(gè)例子，這是丁香假單胞菌。

一旦接觸到番茄， 它就會(huì)侵入果實(shí)和葉子，

在細(xì)胞間隙繁殖，

分泌毒素和蛋白質(zhì)

從而使植株的免疫反應(yīng)失效。

一旦有毒的冠菌素打開了植株的氣孔，

細(xì)菌入侵就暢通無阻了。

冠菌素同時(shí)還能降解葉綠素，

所以我們才會(huì)看到黃色的斑點(diǎn)。

隨著細(xì)菌不斷得到滋養(yǎng)和繁殖，

它們開始?xì)⑺乐仓昙?xì)胞。

這是斑點(diǎn)的由來，但是 塌軟的部分又作何解釋呢？

Those are usually caused when the fruit is attacked by microbes

after it's detached from the plant.

If the plant is wounded during transport,

necrotic fungi can infiltrate ?through the wound,

kill the cells,

absorb their nutrients,

and leave your food ?looking mushy or brown.

Those spots in particular ?can taste pretty bad.

You're eating dead ?and decomposing tissue, after all.

But you can usually salvage the rest of the fruit.

The non-mushy spots, like the ones you typically see on apples or tomatoes,

are just on the surface ?and don't usually affect flavor.

它們通常是在果實(shí)被微生物入侵

并且離開后才形成的。

如果植物在運(yùn)輸過程中表面受到破損，

壞死性真菌可以從傷口滲入

殺死植株細(xì)胞，

榨取養(yǎng)分，

導(dǎo)致食物看起來 呈褐色或者塌軟的樣子。

這類斑點(diǎn)嘗起來尤其難吃。

畢竟你吃下去的 是壞死和分解后的組織。

但是其余完好的部分 還是可放心食用。

你在蘋果或番茄上 常見的沒有塌陷的斑點(diǎn)

只是不美觀，但并不影響味道。

Of course, microbes that do make us sick, like E. coli and salmonella,

can hitch a ride on vegetables, too.

But because they're not plant pathogens, they don't typically cause spots.

They just hang out ?invisibly on the surface.

So it's washing fruit and veggies, not avoiding the spotty ones,

that will help you avoid getting sick.

當(dāng)然，有些微生物是致病的， 比如大腸桿菌和沙門氏菌，

它們也會(huì)搭蔬菜的順風(fēng)車。

但是因?yàn)樗鼈儾皇侵参锊≡?所以不會(huì)導(dǎo)致斑點(diǎn)。

它們只會(huì)無形地附著在表面。

因而正確的做法是清洗蔬果， 而不是避開斑點(diǎn)，

這樣才能讓你預(yù)防疾病。

So the next time ?you're at the grocery store,

don't be afraid ?to pick up funky-looking fruit.

Some stores will even give you a discount.

Wash them well and store them properly,

as some produce like apples and cabbages will keep in the fridge for weeks.

The spotty ones may not be eye candy, but they're safe and just as delicious.

所以下一次你再去買水果，

請放心挑選看上去很丑的水果。

沒準(zhǔn)老板還會(huì)給你優(yōu)惠。

只要洗干凈它們，合理貯藏，

一些農(nóng)產(chǎn)品如蘋果和卷心菜 是可以冷藏保鮮幾個(gè)星期的。

帶斑點(diǎn)的蔬果也許不美觀， 但它們是安全的，而且同樣美味。