63 Oil and Water
To understand the emulsifying process, we must first accept the scientific principle that oil and water do not naturally mix. Quite literally, they find each others presence repulsive. A good illustration of this aversion is homemade oil and vinegar salad dressing.When you shake or beat your salad dressing, you do more than disperse the oil throughout the vinegar: you also break down the oil into droplets minute enough to remain temporarily suspended in the vinegar . The second you stop agitating the dressing, the oil droplets start to combine into units too large to be suspended in the water, and thus slither their way upward, separating from the water in the process. The oil rises to the top and the water sinks because oil has a lower specific density than water. If you want a stable emulsion, you need an emulsifying agent which prevents the oil droplets from combining into larger units. Emulsifying agents occur naturally in many animal substances including egg yolks and milk. An emulsifying agent helps to keep the oil particles from combining in three basic ways. First, the agent coats the oil, serving as a physical barrier between the droplets. Second, it reduces the waters surface tension, which, in turn, reduces the waters ability to repulse oil. Third, the agent gives the surfaces of the oil droplets identical electrical charges; since like charges repel each other the droplets repel each other.
☆英语诗歌欣赏☆ 勿忘我-Forget Me Not
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双语散文:What is Love?
情人节英文诗背诵:你是我心中最美
双语散文:I like the subtle... 我喜欢这种淡淡的感觉
英语晨读:美德
英语晨读:历史上最
心灵鸡汤:爱:能够创造奇迹的力量
英语标准美文78
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The Blessed Dress
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英语美文欣赏:眼里有心
英语美文:别在悲伤的海里沉浮
美文欣赏:给予爱的心伤痕累累却美丽
世界上最美丽英文26
英语美文:美丽的春天
优秀散文赏析:孩子的守护天使
趣味英语小故事:A Bad Foot
心灵鸡汤:成长的树根
美文赏析:给生命定价
英语名篇名段背诵精华18
英语美文欣赏:家=爸爸妈妈
双语散文:一种特别的思绪
精美英文欣赏:人生之笔
心灵鸡汤:感恩节上一颗被感动的心
趣味英语小故事:Shave Me First
英文短篇小说欣赏-失窃的信
双语散文:有感于青春常在
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