Extraction
When a solvent enters in contact with plant material,
it absorbs all the odoriferous substances contained
in that material. Traditionally this method -
called ENFLEURAGE - involved the use of cold fat.
The result of this operation was a pomade or an
odoriferous oil.
Today fat is replaced by volatile solvents (ethanol,
methanol , hexane, toluene, butane or carbon dioxide)
which are heated. These solvents are then eliminated
through evaporation. What is left is a waxy substance
called the concrete. Alcohol is added to the concrete
and the mixture is heated and then chilled During
this process, plant matter and waxes are removed
from the concrete. Once the alcohol is removed
through evaporation,all that is left is the absolute.
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