英语听力文摘 English Digest 543、什么是鲜奶油？！

 　　What Is Whipped Cream?

 

　　It adorns¹ ice cream sundaes, pumpkin² pie, gingerbread, and hot chocolate. Its sweet creaminess tantalizes³ taste buds and sends dieters running from the scale. Did you ever wonder why heavy cream whips into soft, light peaks? You can find out by listening today's moment of science!

 

　　When you whip heavy cream, air is forced into the liquid, and a stable mass of bubbles forms. Each bubble is a tiny pocket of air encircled by a thin film of water with proteins and other substances dissolved in it.

 

　　The protein molecules⁴ that are caught in the bubbles are pushed and pulled by different forces, so they lose their normal shape. Once they lose their normal shape, the protein molecules bond together into a thin film, which stabilizes⁶ the bubble walls.

 

　　The proteins that stabilize⁵ whipped cream are the same as milk proteins, so it would seem that milk would whip into soft shiny peaks as well. But you could whip a bowl of milk all day and never get anything more than a light froth that would disappear almost immediately.

 

　　The difference lies in whipping cream’s high fat content. Whipping cream is from thirty to forty percent fat, in contrast to the four percent fat found in whole milk.

 

　　The fat molecules in cream form a strong, stable network that keeps the bubble walls from collapsing⁷. Small spheres of fat molecules gather together in the bubble walls, where surface forces break open the sphere. The exposed fat molecules stick to each other, and the network forms.

 

　　The fat molecules in milk act similarly, but there aren’t enough of them to stabilize the milk foam⁸ for more than a few seconds.

1 adorns   

装饰，佩带( adorn的第三人称单数 )

参考例句：

• Have adornment, the building adorns the product of material. 有装饰，就有建筑装饰材料的制品。
• In this case, WALL-E adorns every pillar. 在这段时间，Wall-E占据了各个显要位置。

2 pumpkin   

n.南瓜

参考例句：

• They ate turkey and pumpkin pie.他们吃了火鸡和南瓜馅饼。
• It looks like there is a person looking out of the pumpkin!看起来就像南瓜里有人在看着你！

3 tantalizes   

v.逗弄，引诱，折磨( tantalize的第三人称单数 )

参考例句：

4 molecules   

分子( molecule的名词复数 )

参考例句：

• The structure of molecules can be seen under an electron microscope. 分子的结构可在电子显微镜下观察到。
• Inside the reactor the large molecules are cracked into smaller molecules. 在反应堆里，大分子裂变为小分子。

5 stabilize   

vt.（使）稳定，使稳固，使稳定平衡；vi.稳定

参考例句：

• They are eager to stabilize currencies.他们急于稳定货币。
• His blood pressure tended to stabilize.他的血压趋向稳定。

6 stabilizes   

n.（使）稳定， （使）稳固( stabilize的名词复数 )v.（使）稳定， （使）稳固( stabilize的第三人称单数 )

参考例句：

• The broadbased attachment of the mesenteric root stabilizes the small bowel. 肠系膜根部基底宽阔的附着面使小肠得以稳定。 来自辞典例句
• The available supply of industrial product and produce stabilizes growth. 工业品与农产品的有效供给稳定增长。 来自互联网

7 collapsing   

压扁[平]，毁坏，断裂

参考例句：

• Rescuers used props to stop the roof of the tunnel collapsing. 救援人员用支柱防止隧道顶塌陷。
• The rocks were folded by collapsing into the center of the trough. 岩石由于坍陷进入凹槽的中心而发生褶皱。

8 foam   

v./n.泡沫，起泡沫

参考例句：

• The glass of beer was mostly foam.这杯啤酒大部分是泡沫。
• The surface of the water is full of foam.水面都是泡沫。