题干

甘薯和马铃薯都富含淀粉,但甘薯吃起来比马铃薯甜。为探究其原因,某科学兴趣小组做了下列探究工作。

【查阅资料】通过上网获得以下信息淀粉粉是无甜味的,淀粉在酶的作用下能初步分解成有甜味的麦芽糖。

【做出猜想】甘薯中可能含有淀粉酶,把淀粉初步催化分解为具有甜味的麦芽糖,而马铃薯中则不含淀粉酶。

【实验操作】把甘薯、马铃薯放置在不同温度下,控制其他条件相同,处理30分钟,测定麦芽糖含量。结果表明马铃薯处理后不含麦芽糖,甘薯处理后的麦芽糖含量如下表:

处理温度 (℃)

0

10

20

30

40

50

60

70

80

90

甘薯中麦芽糖含量(毫克/克)

22.1

23.3

25.8

37.6

40.5

47.4

54.7

68.9

45.3

28.6

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