1. Plant Oils Noadswood Science, 2011

2. Plant Oils To know how plants make oils, and how these are extracted Wednesday, September 09, 2015

3. Anagrams Try and solve the following anagrams: - Nkalea Eatatsdur Iilsttioladn Onoremm Plmeroy Uredaanstut Eostningethormf Droanbroych Nkgricca Alkane Saturated Distillation Monomer Polymer Unsaturated Thermosoftening Hydrocarbon Cracking

4. Plant Oil What are vegetable oils? Vegetable oils are natural oils found in seeds, nuts and some fruit The plant materials are crushed and pressed to squeeze the oil out (e.g. olive oil is obtained this way) Sometimes the oil is more difficult to extract and has to be dissolved in a solvent – once the oil is dissolved, the solvent is removed by distillation, and impurities such as water are also removed, to leave pure vegetable oil (e.g. sunflower oil is obtained in this way)

5. Extraction Plant oil extraction is relatively simple, involving two steps: - Crush the plant Remove the oil by pressing or via distillation Or

6. Orange Peel Distillation Watch the demo of the orange peel distillation…

7. Plant Oil Molecules of vegetable oils consist of glycerol and fatty acids: - Glycerol has three carbon atoms Fatty acids have long chains of carbon atoms Three long chains of carbon atoms are attached to a glycerol molecule (with its three carbon atoms) – together they combine to make one molecule of vegetable oil…

8. Fatty Acids Thee long fatty acid chains stop vegetable oils dissolving in water The fatty acids in some vegetable oils are saturated, and only have single bonds between their carbon atoms Saturated oils tend to be solid at room temperature, and are sometimes called vegetable fats instead of oils Lard is an example of a saturated oil

9. Fatty Acids The fatty acids in some vegetable oils are unsaturated, and have double bonds between some of their carbon atoms Unsaturated oils tend to be liquid at room temperature, and are useful for frying food They can be divided into two categories: - Monounsaturated fats have one double bond in each fatty acid Polyunsaturated fats have many double bonds

10. Unsaturation The carbon-carbon double bonds in unsaturated oils can be detected using the elements bromine or iodine – these elements react with the double bonds in the oils, and the more double bonds there are, the more bromine or iodine is used up Unsaturated fats can be tested for using a simple test with bromine water – bromine water is a dilute solution of bromine, which is normally orange-brown in colour which becomes colourless when shaken with an alkene, or with unsaturated fats When shaken with alkanes or saturated fats, its colour remains the same

11. Unsaturation