Infusion is the process of extracting chemical compounds or flavors from plant material in a
solvent
A solvent (from the Latin language, Latin ''wikt:solvo#Latin, solvō'', "loosen, untie, solve") is a substance that dissolves a solute, resulting in a Solution (chemistry), solution. A solvent is usually a liquid but can also be a solid, a gas ...
such as water,
oil or
alcohol
Alcohol may refer to:
Common uses
* Alcohol (chemistry), a class of compounds
* Ethanol, one of several alcohols, commonly known as alcohol in everyday life
** Alcohol (drug), intoxicant found in alcoholic beverages
** Alcoholic beverage, an alco ...
, by allowing the material to remain suspended in the solvent over time (a process often called
steeping
Steeping is the soaking of an organic solid, such as leaves, in a liquid (usually water) to extract flavours or to soften it. The specific process of teas being prepared for drinking by leaving the leaves in heated water to release the flavour ...
). An infusion is also the name for the resultant liquid. The process of infusion is distinct from both
decoction—a method of extraction involving boiling the plant material—and
percolation
In physics, chemistry, and materials science, percolation () refers to the movement and filtration, filtering of fluids through porous materials. It is described by Darcy's law. Broader applications have since been developed that cover connecti ...
, in which water is passed through the material (as in a
coffeemaker).
History
The first recorded use of
essential oil
An essential oil is a concentrated hydrophobic liquid containing volatile (easily evaporated at normal temperatures) chemical compounds from plants. Essential oils are also known as volatile oils, ethereal oils, aetheroleum, or simply as the ...
s was in the 10th or 11th century by the
Persian polymath
A polymath or polyhistor is an individual whose knowledge spans many different subjects, known to draw on complex bodies of knowledge to solve specific problems. Polymaths often prefer a specific context in which to explain their knowledge, ...
Avicenna
Ibn Sina ( – 22 June 1037), commonly known in the West as Avicenna ( ), was a preeminent philosopher and physician of the Muslim world, flourishing during the Islamic Golden Age, serving in the courts of various Iranian peoples, Iranian ...
, possibly in ''
The Canon of Medicine
''The Canon of Medicine'' () is an encyclopedia of medicine in five books compiled by Avicenna (, ibn Sina) and completed in 1025. It is among the most influential works of its time. It presents an overview of the contemporary medical knowle ...
''.
Tea is far older than this, dating back to the 10th century BC as the earliest recorded reference.
Preparation techniques
Infusion is a chemical process that uses
botanicals (typically dried herbs, flowers or berries) that are volatile and release their active ingredients readily in water, oil, or alcohol. In this process, a liquid is typically boiled (or brought to another appropriate temperature) and poured over the herb. After the herb has been allowed to steep in the liquid for an appropriate period of time, it is removed (possibly by straining) leaving ''an infusion''. Unless the infusion is to be consumed immediately, it is bottled and refrigerated for future use.
The amount of time the herbs are left in the liquid depends on the kind of infusion. Infusion times can range from seconds (for some kinds of
Chinese tea) to hours, days, or months (for liqueurs like
sloe gin).
There are several accessories and techniques for removing the steeped or leftover botanicals that were used to infuse liquids, including metal steepers (which look like clamps), tea infusers (which act as strainers), and French presses (which are commonly used to infuse water with various teas and coffee). The most commonly used technique is the teabag, which is made with filter paper and filled with various tea flavors.
Examples

*
Tea is a common example of an infusion; most varieties of tea call for steeping the leaves in hot water, although some variants (e.g.
Moroccan mint tea) call for
decoction instead. Many
herbal tea
Herbal teas, technically known as herbal infusions, and less commonly called tisanes (UK and US , US also ), are beverages made from the infusion or decoction of herbs, spices, or other plant material in hot water. Often herb tea, or the plai ...
s are prepared by infusion, as well; lemon,
chamomile
Chamomile (American English) or camomile (British English; see spelling differences) ( or ) is the common name for several plants of the family Asteraceae. Two of the species, '' Matricaria chamomilla'' and '' Chamaemelum nobile'', are commo ...
, senna, apple, ginger,
rooibos, and many other plants are used individually or in combination.
*
Coffee
Coffee is a beverage brewed from roasted, ground coffee beans. Darkly colored, bitter, and slightly acidic, coffee has a stimulating effect on humans, primarily due to its caffeine content, but decaffeinated coffee is also commercially a ...
can also be made through infusion (as in a
French press), but is more often made through
percolation
In physics, chemistry, and materials science, percolation () refers to the movement and filtration, filtering of fluids through porous materials. It is described by Darcy's law. Broader applications have since been developed that cover connecti ...
.
*
Herbal remedies are commonly produced through infusions in water or oil.
* Flavored oils: Plants with desirable flavors may be steeped in an
edible oil or
vinegar for an extended period; the infused oil or vinegar is often sold still containing the plant and is then used as flavoring. Chilis, lemon, garlic, and many other plants may be used. There can be ambiguity in the labeling of these oils: for example, what is described as
sesame oil may be oil extracted from
sesame seed
In botany, a seed is a plant structure containing an embryo and stored nutrients in a protective coat called a ''testa''. More generally, the term "seed" means anything that can be Sowing, sown, which may include seed and husk or tuber. Seeds ...
s or another vegetable oil infused with sesame.
* Cucumber water, a mix of sliced
cucumber with citrus slices and herbs such as mint, is a popular infusion.
It is sometimes known as "spa water" due to it being commonly served in
day spas and similar personal care establishments.
See also
*
Mate
*
Aromatherapy
*
Chinese herbology
*
Decoction
*
Herbalism
Herbal medicine (also called herbalism, phytomedicine or phytotherapy) is the study of pharmacognosy and the use of medicinal plants, which are a basis of traditional medicine. Scientific evidence for the effectiveness of many herbal treatments ...
*
List of cooking techniques
*
Tincture
*
Maceration (food)
*
Percolation
In physics, chemistry, and materials science, percolation () refers to the movement and filtration, filtering of fluids through porous materials. It is described by Darcy's law. Broader applications have since been developed that cover connecti ...
*
Coffee steeping
References
External links
*
*
{{Cooking Techniques
Aromatherapy
Cooking techniques