一分子结晶水柠檬酸主要用作清凉饮料、果汁、果酱、水果糖和罐头等食品工业中,其主要主要作用为:
A. 酸性调味剂
B. 防腐剂
C. 抗氧化剂
D. 增强食欲和促进体内钙、磷物质的消化吸收
查看答案
柠檬酸可以以无水合物或者一水合物的形式存在,柠檬酸从热水中结晶时,生成();在冷水中结晶则生成( )
从结构上讲柠檬酸是一种三羧酸类化合物,并因此而与其他( )有相似的物理和化学性质。加热至175°C时它会分解产生( )和水,剩余一些白色晶体。
2 Conversation: Why Don’t We Have Lunch Together?A. Listen to the following conversation and then decidewhether each of the statements below is true (T ) orfalse (F ).[音频][音频]_____ 1. Jill and Sue have known each other for some time._____ 2.They are very surprised to run into each other.______3. Jill is teaching in Hong Kong now.______ 4. Both Jill and Sue are single.______ 5. Jill gives Sue her card.