Cosmetic Science brings together aspects of Chemistry, physiology and dermatology and blends knowledge and skills in design, formulation, manufacturing, quality control and marketing to create the cosmetic products which are used in every day life. It can take up to 10 years to become a perfumer and requires gaining qualifications in chemistry as well as a good sense of smell!
Cosmetics are products which have been used since ancient times to change the way the body looks or smells and can contain either naturally occurring or artificial ingredients.
Lots of substances used in cosmetic products today are plant extracts including oils, carbohydrates and edible fats. Essential oils, which are mixtures of many different compounds and give plants their scents are also used. Some of these essential oils also have antiseptic and anti fungal properties. Different essential oils can have different effects on our bodies, some can have a calming effect while others help make people feel energised. Essential oils can be expensive due to the volume of material required to extract them, for example it would take 5 tonnes of roses to produce 1kg of rose essential oil.
Essential oils can be extracted in a number of ways from plants, including cold pressing, using a solvent or steam distillation which is the most common method used. Steam distillation involves passing steam through shredded plant material to allow the essential oils to vaporise before being carried into a condenser where they form an oily layer on top of the water in the flask. Cold pressing means squeezing the plant material to burst the checks and release their essential oils. (Try squeezing your fingernails into the skin of an orange to get a similar effect!)
Research the following essential oils and find out what part of the plant is used to extract the oil and some of the uses associated with each oil: Lavender, Lemon, Peppermint, Eucalyptus, Sandalwood.
Essential oils can be grouped into top, middle or base notes according to how long their scent lasts. Create a table showing different essential oils organised into these groups by carrying out further research.
Carbohydrates are energy foods but are also used in the cosmetic industry. Agar and alginates, extracted from seaweed are examples of carbohydrates used in the cosmetics industry. Many face masks contain agar extracted from red seaweed for example.
Fats and oils are also used including Cocoa butter found in moisturisers and lip balms which is extracted from cocoa beans and used in making chocolate. Castor oil, extracted from castor beans, is often used in lipsticks as it forms a tough, shiny film when it dries.
Explore the ingredients listed on cosmetic products around your home and create a video on cosmetic science. You may wish to share this on Twitter using the #STEMglasgow
