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Making them sweeter
JAPANESE scientists have developed a special kind of tomato. It can change an eater's sense of
taste,says a report in Science News. For about an hour after a person eats one of the tomatoes,sour foods taste sweet.
Say you eat one of the tomatoes before lunch. Then you take a bite of a lemon (柠檬). You will
find that the lemon tastes like super-sweet lemonade.
How magical is that ! The key ingredient in the taste-changing tomatoes is " miraculin (非洲奇果蛋白 ) ". Miraculin is found in berries that grow in West Africa. These fruits are sometimes sold as "
Miracle(奇迹) Fruit" berries.
People have long known about the ability of miracle berries to change taste. In some countries,the
berries are used as a way to help people lose weight: For example,a dieter can eat a berry and then eat
low-calorie sour foods that will
taste wonderfully sweet.
Scientists found miraculin in the miracle berry in 1968. Since then,people have wondered how to
manufacture it. One way could be to harvest the berries. The problem was that if demand got too large,
the berry plants could be driven to extinction.
That's where the Japanese scientists came in. Professor Kazuhisa Kato and his team at the University of Tsukuba studied the DNA of the miracle berry. They found a gene(基因) that contained the
instructions for how to make miraculin.
Kato and other researchers put the gene for miraculin into the DNA of a tomato. As a result,the
tomatoes started to make miraculin. Those tomatoes had just as much miraculin as miracle berries do.
These "miracle" tomatoes could be grown in large numbers. If scientists can grow other foods with
miraculin inside,then there won't be any need to harvest all the miracle berries.
The researchers don't know yet how the tomato-based miraculin can be used. Perhaps it could be sold as a dieting food,to be taken before meals.
1. The tomato is special in that___.
A. it tums all tastes sweet
B. it can only be eaten before lunch
C. it changes a sour taste to a sweet one
D. it has a magical ingredient
2. According to the article,the Japanese scientists____.
A. found a gene that contained instructions for making miraculin
B. discovered the secrets of miracle fruit berries in 1968
C. have planted miracle tomatoes in large numbers
D. invented the miraculin gene and put it into the tomato=
3. According to the article,which of the following statements is TRUE?
A. It was a latest discovery that miracle berries could change taste.
B. The tomato is a low-calorie fruit that tastes wonderfully sweet.
C. Scientists have already found many uses for mariculin.
D. The tomato-based miraculin might help people lose weight,so it might be used as a dieting food.
