A florentine flask, also known as florentine receiver, florentine separator or essencier (from the French), other shapes called florentine vase or florentine vessel, is an
oil–water separator
An oil water separator (OWS) is a piece of equipment used to separate oil and water mixtures into their separate components. There are many different types of oil-water separator. Each has different oil separation capability and are used in differ ...
fed with condensed vapors of a steam distillation in a
fragrance extraction
Fragrance extraction refers to the separation process of aromatic compounds from raw materials, using methods such as distillation, solvent extraction, expression, sieving, or enfleurage. The results of the extracts are either essential oils, ...
process.
Description
When the raw material is heated with steam from boiling water, volatile fragrant compounds and steam leave the
still
A still is an apparatus used to distill liquid mixtures by heating to selectively boil and then cooling to condense the vapor. A still uses the same concepts as a basic distillation apparatus, but on a much larger scale. Stills have been use ...
. The vapours are cooled in the
condenser and become liquid. The liquid runs into the florentine receiver where the water and essential oil phases separate.
The essential oils phase separates from water because the oils have a different density than water, and are not water-soluble.
There are two main types of florentines in use. One separates essential oils of lower density than water, for example
lavender oil
Lavender oil is an essential oil obtained by distillation from the flower spikes of certain species of lavender. There are over 400 types of lavender worldwide with different scents and qualities. Two forms of lavender oil are distinguished, '' ...
, accumulating in a layer floating on the water.
This kind of florentine has to be airtight to reduce the loss of volatile substances.
The other type is intended for oils that are denser than water, where the oil accumulates beneath the water phase, for instance
cinnamon,
wintergreen
Wintergreen is a group of aromatic plants. The term "wintergreen" once commonly referred to plants that remain green (continue photosynthesis) throughout the winter. The term "evergreen" is now more commonly used for this characteristic.
Most ...
,
vetiver
''Chrysopogon zizanioides'', commonly known as vetiver and khus, is a perennial bunchgrass of the family Poaceae.
Vetiver is most closely related to '' Sorghum'' but shares many morphological characteristics with other fragrant grasses, such a ...
,
patchouli
PatchouliAlso spelled ''patchouly'' or ''pachouli''. (; ''Pogostemon cablin'') is a species of flowering plant in the family Lamiaceae, commonly called the mint or deadnettle family. The plant grows as a bushy perennial herb, with erect stems r ...
or
cloves.
The floating water phase avoids the loss of volatile compounds from the oil.
There are also florentines that are able to accommodate oils that are denser or less dense than water.
The separated water is a
herbal distillate
Herbal distillates, also known as floral waters, hydrosols, hydrolates, herbal waters, and essential waters, are aqueous products of hydrodistillation. They are colloidal suspensions of essential oils as well as water-soluble components obtained ...
and can be fed back into the still or may in some cases be sold as herbal water.
Because small droplets of oil are entrained with the water flowing out of the florentine, the yield can sometimes be increased by using more than one florentine in series.
For laboratory use, a small glass florentine without a base is called a ''florentine vase'', as it has a slight resemblance to a small
amphora. Larger glass receivers with base are called ''florentine flasks'' or ''essenciers''.
Glass is normally only used up to 15 liter vessels; above this size, glass is too fragile, so that metal is used for larger capacities.
References
{{Reflist
Essential oils
Flavor technology
Liquid-liquid separation
Distillation