问题 问答题 简答题

从复式糖化法的典型曲线说明各点各线段的工作原理,你能否从某一麦芽的特性(告诉你麦芽的质量)和酿造啤酒的类型制订出合理的糖化操作曲线。

答案

参考答案:

①酸休止:利用麦芽中磷酸酯酶对麦芽中菲汀进行水解,产生酸性磷酸盐。

②蛋白质休止:利用麦芽中的内、外肽酶水解蛋白质形成多肽和氨基酸。

③100℃煮出:部分糖化醪加热至100℃,利用热力作用,使淀粉彻底糊化、液化,提高浸出物收率。

④糖化终了:除α-淀粉酶外,其它酶钝化。糊化锅(大米粉PH6.2)50℃93℃(15min)100℃(30min)→[糊化锅(麦芽粉PH5.3)50℃→]63℃(30min)→68℃(40min碘反应完全)→78℃(10min)→过滤

复式糖化法(一次、二次是指糖化的次数)糖化时先在糊化锅中对不发芽谷物进行预处理——糊化、液化(即对辅料醪进行酶分解和煮出),然后在糖化锅进行糖化的方法。此法辅料中淀粉利用率高,用于添加非发芽谷物为辅料生产下面发酵啤酒。复式一次煮出糖化法适合于各类原料酿造浅色麦汁,复式浸出糖化法常用于酿制淡爽型啤酒。升温浸出糖化法要求麦芽发芽率高,溶解充分。降温浸出糖化法一般很少采用。一次煮出-浸出糖化法要求麦芽质量好、酶活高;若麦芽质量普通,麦芽酶活力不足,应适当补充合适的酶制剂,采用二次煮出糖化法。三次煮出糖化法适合与各种质量麦芽。糖化力强、溶解良好的麦芽,糖化的时间短,形成可发酵性糖多,可采用较低糖化温度作用。

完形填空

Lang Lang is a world-class young pianist who grew up in Shenyang. He went to a piano school in Beijing when he was just eight. “You need luck,” his father said. “But if you don’t work hard, no fortune will come.”

What made him sad was that his piano teacher in Beijing didn’t like him. “You have no talent. You will never be a pianist.” As a nine-year-old boy, Lang Lang was badly hurt. He decided that he didn’t want to be a pianist any more. For the next two weeks, he didn’t touch the piano. Wisely, his father didn’t push, but waited.

Luckily, the day came when his teacher asked him to play some holiday songs. He didn’t want to, but as he placed his fingers in the piano keys, he realized that he could show others that he had talent after all. That day he told his father what he had been waiting to hear---that he wanted to study with a new teacher. From that point on, everything turned around.

He started to win competitions and then became famous at home and abroad. Lang Lang finally worked to reach the place where fortune finds him, and lets him shine.

 

小题1: Which city is Lang Lang’s hometown? (用完整句子回答)

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小题2: Which word has the same meaning as “luck” (in the first paragraph) in the article?

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小题3:Please translate the underlined sentence into Chinese.

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小题4: Lang Lang’s father is a ________ father, who is different from other fathers. (此空填一词)

小题5:How do you understand “a good teacher”? (用定语从句回答)

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