Section C

Directions: In this section, you will hear a passage three times. When the passage is read for the first time, you should listen carefully for its general idea. When the passage is read for the second time, you are required to fill in the blanks numbered from 36 to 43 with the exact words you have just heard. For blanks numbered from 44 to 46 you are required to fill in the missing information. For these blanks, you can either use the exact words you have just heard or write down the

Why does cream go bad faster than butter? Some researchers think that it comes down to the structure of the food, not its chemical【B1】_______ --a finding that could help rid some processed foods of chemical preservatives.

Cream and butter contain much the same【B2】_______ , so why cream should sour much faster has been a【B3】_______ . Both are emulsions--tiny globules of one liquid evenly【B4】_______ throughout another. The difference lies in what's in the globules and what's in the surrounding. In cream, fatty globules drift about in a sea of water. In butter, globules of a watery【B5】_______ are locked away in a sea of fat. The bacteria which make the food go bad prefer to live in the watery regions of the【B6】_______ . This means that in cream, the bacteria are free to grow throughout the mixture. When the situation is【B7】_______ , the bacteria are locked away in【B8】_______ buried deep in the sea of fat.【B9】_______ . They also slowly poison themselves with their waste products.

In butter, there is a self-limiting system which stops the bacteria from growing.【B10】_______ . It is believed that it will be possible to make the emulsions used in salad cream, for instance, more like those in butter.【B11】_______ .

【B1】