Fragranes and skincare Flashcards
what are essential oils?
concentrated extracts of the volatile (evaporated easily), non-water soluble aroma compounds from plants
What are essential oils mixtures of?
many different compounds used in perfumes, cosmetic products, cleaning products and as flavourings in food
What is a key component in most essential oils
terpenes
What are all terpenes made from?
The same basic unit:
isoprene (2-methylbuta-1,3-diene)
find diagram in jotter
CH3
I H2C==C—C==CH2
I
H
2double bonds
methyl position nom2
These join end to end or in a ring (and react with other species) to give terpenes
Number of Cs in a terpene
multiple of 5
What happens when a terpene is oxidised within plants
Produce some of the compounds responsible for the distinctive aroma of spices (terpenoids)
steam distillation (check jotter)
-glass wool
-bunsen burner
-water and anti-bumping granules
-source of oil eg cloves
-condenser (tissue soaked in cold water
-iced water
- distillate (oil and water mix)
What would happen if we were to use normal distillation?
organic (living) matter decomposes at sustained high temperatures
What is a free radical
a highly reactive species (atoms or molecules) with an unpaired valence (in outer shell) electron
What are radicals shown with in formulas?
a dot
How does the original chlorine molecule break?
by homolyctic fission
one electron from the covalent bond goes onto each atom shown by single headed arrows
initiation, propagation and termination
initiation-free radicals after arrow
propagation-free radicals on both sides of arrow
termination-free radicals before arrow
How are free radicals formed?
When UV light breaks bonds, free radicals are formed
UV light can provide sufficient energy to break bonds within molecules.
What does UV light cause in skin?
sunburn and accelerated aging in the skin
What is Ultraviolet (UV) radiation?
a high-energy light, present in sunlight
