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  • Created on: 28-04-11 11:50
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Extraction methods
Distillation converts the volatile liquid
into a vapour and then condenses the
vapour back into a liquid. This gives us oils
such as tea tree oils. Vegetable fats and
oils are lipid materials derived from plants
An emulsion is a mixture of two or more immiscible (unblendable) liquids. Emulsions
are part of a more general class of twophase systems of matter called colloids.
Although the terms colloid and emulsion are sometimes used interchangeably, emulsion
tends to imply that both the dispersed and the continuous phase are liquid. In an
emulsion, one liquid (the dispersed phase) is dispersed in the other (the continuous
Hardening of oil into butter
Vegetables fats and oils are fat materials delivered from plants. Physically, oils are
liquid at room temperature, and fats are solid. Chemically, both fats and oils are
composed of triglycerides, as contrasted with waxes which lack glycerine in their
structure. Although many different parts of plants may yield oil, in commercial practice,
oil is extracted primarily from seeds.
Biodiesel refers to a vegetable oil or animal fatbased diesel fuel consisting of
longchain alkyl (methyl, propyl or ethyl) esters. Biodiesel is typically made by chemically
reacting lipids (e.g., vegetable oil, animal fat (tallow)) with an alcohol.

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Food additives are substances added to food to preserve flavour or improve its taste
and appearance. Some additives have been used for centuries for example,
preserving food by pickling (with vinegar), salting, as with bacon, preserving sweets or
using sulfur dioxide as in some wines. With the advent of processed foods in the
second half of the 20th century, many more additives have been introduced, of both
natural and artificial origin.…read more


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