问题 问答题 论述题

食品腐败变质的原因、化学过程、鉴定指标,食品卫生学意义及其预防措施、处理原则。

答案

参考答案:

食品腐败变质:泛指在微生物为主的各种因素作用下,食品降低或失去食用价值的一切变化。或食品腐败变质就是食品失去商品价值。

食品腐败变质的原因:是以食品本身的组成和性质为基础,在环境因素影响下,主要由微生物的作用而引起。

食品腐败变质的过程:是在微生物酶、食品酶和其他因素作用下食品组成成分的分解过程。

食品腐败变质的鉴定:一般采用感官、物理、化学和微生物四个方面的指标。

食品腐败变质的卫生学意义:食品的腐败变质使食品感官性质发生改变,食物营养价值严重降低。同时腐败变质的食物一般微生物污染严重,使致病菌和产毒霉菌存在的机会增多,引起人的不良反应,有时对人体造成直接的损害。

防止食品腐败变质的措施:对食品进行加工处理,延长食品可供食用的期限,即进行有效的食品保藏。

处理原则:确保人体健康。

阅读理解

阅读理解。

     I took my dog, Phil, to the vet's (兽医诊所) yesterday. When the doctor came into the room, he was

limping (跛行).

     "What's wrong?" I said. "Oh, it's my knee. They want me to really appreciate the operation I'm about to have, so they delayed it another month, so I would suffer more," he replied.

     It was then for the first time I actually showed my scar to someone. "Look, I had an operation on my

arm." My wife has been telling me that it really didn't look bad. It healed very nicely. When I showed it to

the doctor and his assistant, they said, "That's terrible!"

     That's when I discovered something.

     "Doctor, when I was a kid, I fell. I remember showing the scar to all my friends because I thought it

was 'cool'. Having a scar at that age was like having a battle injury."

     "Then I went into the young adulthood and vanity (虚荣心) took over. I was in a band and never

wanted anything to scar my beautiful face. Now, at 59, I just joined that group of older folks who are

proud to compare operations, aches and pains," I said struggling to get it out without laughing.

     The winner is the one who is in the worst shape, I guess. Then there are those at any age, who use their scars as an excuse. The kind of excuse holds them back, limits them and provides a crutch for why they

aren't happy. "Too short"... "too fat"... "my family"... "ever since we had children" and so on.

     All scars never heal because we keep picking at (扯拉) them. I promised I'd never do that, yet today I didn't even hesitate to show the doctor my scar. It's okay. I see it as returning to my childhood. What

scars do you have?

1. The doctor would limp for another month because _____.

A. he wanted to show it to the author

B. his operation was put off

C. he was proud to suffer from it  

D. he was too busy to receive the operation

2. The author felt bad about his scars when he was _____.

A. a baby  

B. a teenager

C. a young adult  

D. a middle-aged man

3. As a child, the author _____.

A. often compared aches with others  

B. was proud to wear a scar

C. often fought with other kids          

D. had an operation on his forehead

4. The underlined word "crutch" in the passage most probably means "_____".

A. support  

B. injury  

C. experience  

D. chance

5.The passage suggests that we should _____.

A. avoid showing our scars              

B. fight against our scars

C. be optimistic about our scars    

D. show off our scars to others

名词解释