★英語聽力頻道為大家整理的英語聽力練習mp3：千層面的怨念，供大家參考。更多閱讀請查看本站英語聽力頻道。
你昨晚做了千層面，而且非常美味。
So you made lasagna last night, and it was delicious.
你將剩下的千層面用鋁箔紙包好放入冰箱中。
You saved the leftovers by wrapping aluminum foil over the top of the pan, and putting it in the fridge.
今天你餓的時候，便去拿昨天吃剩的千層面，但是你會發(fā)現千層面似乎也餓了！
When you get hungry today, you go to look for that lasagna, but it looks like the lasagna was getting hungry too!
包裹它的鋁箔紙上出現了一個個的小洞，好像被咬過一樣。
It's eaten tiny holes in the aluminum foil that was covering it.
為什么會這樣呢？
Why does this happen?
一位聽眾問到了這個問題，我們將在今天的科學一刻中為你解答。
A listener asked this question and we'll find the answer on today's moment of science.
鋁箔上出現這些洞有兩個原因：一個是千層面本身具有酸性，另一個就是鋁具有一些非常奇特的屬性。
千層面.jpg
There are really two things responsible for those holes in the aluminum foil: the acidic nature of the lasagna and some curious properties of aluminum.
千層面的酸性主要是來自醬汁中的番茄醬。
Lasagna gets most of it's acid from the tomatoes in its sauce.
幾乎你吃的每樣東西都會至少呈輕微酸性，而番茄的酸性尤為明顯。
Almost everything you eat is at least slightly acidic, but tomatoes are especially so.
這種酸對玻璃容器，不銹鋼，塑料袋或大多數我們用于儲藏和準備食物所用的材料都不會產生任何影響。
This acid wouldn't be a problem for a glass container, or stainless steel, or plastic wrap, or for most of the materials we use to store and prepare food.
但鋁卻非常容易受到酸的侵蝕。
Aluminum, though, is especially vulnerable to acid.
這就是原因。
Here's why.
大多數金屬會在表面生成一種叫做氧化層的保護膜。
Most metals form a protective layer on their surface called an oxide layer.
鋁金屬也會形成氧化層，但是這層膜很薄，番茄中的酸能輕易腐蝕透。
Aluminum forms an oxide layer too, but it is very thin, allowing the tomato's acid to easily break through.
由此番茄醬就會溶解鋁，在千層面上產生一種灰色或黑色的化學物質，會使千層面變得非常難吃。
This lets the tomato sauce dissolve the aluminum, and it creates grey or black chemicals on top of the lasagna that taste very bad.
如果用鋁制廚具來做酸味兒醬料，也會發(fā)生相同的情況。
The same thing can happen if you use aluminum cookware for acidic sauces.
鋁制鍋所做的醬料顏色看起來會更灰些，吃起來也不如其他廚具所做的醬料味道好。
Sauce made in an aluminum pot will be grayer and not as tasty as sauce made in other cookware.
你昨晚做了千層面，而且非常美味。
So you made lasagna last night, and it was delicious.
你將剩下的千層面用鋁箔紙包好放入冰箱中。
You saved the leftovers by wrapping aluminum foil over the top of the pan, and putting it in the fridge.
今天你餓的時候，便去拿昨天吃剩的千層面，但是你會發(fā)現千層面似乎也餓了！
When you get hungry today, you go to look for that lasagna, but it looks like the lasagna was getting hungry too!
包裹它的鋁箔紙上出現了一個個的小洞，好像被咬過一樣。
It's eaten tiny holes in the aluminum foil that was covering it.
為什么會這樣呢？
Why does this happen?
一位聽眾問到了這個問題，我們將在今天的科學一刻中為你解答。
A listener asked this question and we'll find the answer on today's moment of science.
鋁箔上出現這些洞有兩個原因：一個是千層面本身具有酸性，另一個就是鋁具有一些非常奇特的屬性。
千層面.jpg
There are really two things responsible for those holes in the aluminum foil: the acidic nature of the lasagna and some curious properties of aluminum.
千層面的酸性主要是來自醬汁中的番茄醬。
Lasagna gets most of it's acid from the tomatoes in its sauce.
幾乎你吃的每樣東西都會至少呈輕微酸性，而番茄的酸性尤為明顯。
Almost everything you eat is at least slightly acidic, but tomatoes are especially so.
這種酸對玻璃容器，不銹鋼，塑料袋或大多數我們用于儲藏和準備食物所用的材料都不會產生任何影響。
This acid wouldn't be a problem for a glass container, or stainless steel, or plastic wrap, or for most of the materials we use to store and prepare food.
但鋁卻非常容易受到酸的侵蝕。
Aluminum, though, is especially vulnerable to acid.
這就是原因。
Here's why.
大多數金屬會在表面生成一種叫做氧化層的保護膜。
Most metals form a protective layer on their surface called an oxide layer.
鋁金屬也會形成氧化層，但是這層膜很薄，番茄中的酸能輕易腐蝕透。
Aluminum forms an oxide layer too, but it is very thin, allowing the tomato's acid to easily break through.
由此番茄醬就會溶解鋁，在千層面上產生一種灰色或黑色的化學物質，會使千層面變得非常難吃。
This lets the tomato sauce dissolve the aluminum, and it creates grey or black chemicals on top of the lasagna that taste very bad.
如果用鋁制廚具來做酸味兒醬料，也會發(fā)生相同的情況。
The same thing can happen if you use aluminum cookware for acidic sauces.
鋁制鍋所做的醬料顏色看起來會更灰些，吃起來也不如其他廚具所做的醬料味道好。
Sauce made in an aluminum pot will be grayer and not as tasty as sauce made in other cookware.