GCSE chemistry unit 1 - plant oils

Plant oils

Oils from plants are useful:

• They contain nutrients and energy
• Give a much higher energy content to food
• Give different flavours to food
• Are used in cosmetics
• Can be used in biofuels (more renewable fuels)

They can be made in two ways:

• STEAM DISTILLATION
• OR PULPING THE FRUIT

Steam distillation

As the plant material and water is heated, the plant oils and steam is evaporated but then condenses when it reaches the cooling jacket. The products are two separate liquids: water and plant oil. It is simple to separate them because they are not mixed.

Pulping the fruit

Plant or fruit is crushed to a pulp and then squeezed. The squeezed oils are purified, removing water and impurities and is now pure oil. The pulp or seed left over are dissolved in a solvent to create oil. The solvent and oil are then separated to create even more pure oil. There is little waste.