The group of essential oils making up the Citrus group are some of the most accessible and well-loved essential oils. Their fresh clean aroma is enjoyed by most people – adults and children alike.
Citrus essential oils are produced in a very different way to most essential oils which are steam distilled. By contrast, the citrus essential oils are the only ones produced by expression, a method whereby the skin of the fruits are crushed to extract the essential oil. No other substance nor any heat is used in their production. (In fact some producers refer to the extraction method as “cold-pressing”.)
While some citrus fruits are also available in a distilled form, it should be noted that this method uses the whole fruit, rather than just the peel, so the resulting essential oil is different in appearance, aroma and in its chemical constituents, from the expressed oil from the peel alone.
Even if you have not experienced a citrus essential oil from a bottle, you likely have experienced it in the kitchen. The next time you eat an orange or mandarin, or squeeze a lemon or lime, take a look at the peel. You will see lots of little bumps over the surface and it is these that contain the essential oil. If you squeeze the peel you may even see some small drops of the essential oil. When we use the “zest” of a citrus fruit in a recipe, we are capturing the same wonderful aroma as is in the essential oil.
This different method of extraction has a profound effect on the character of the essential oil.
Because citrus essential oils are not subject to the steam distillation process, the essential oil aroma is often more true to its origin. In contrast, the process of distillation can result in differences between a plant source and its essential oil, due to some chemical components not coming across in the distillation process. The process of expression also enables the citrus oils to include molecules of heavier constituents that would not come across in a distilled oil.
Not being subjected to heat in their production, and containing a high proportion of monoterpenes, citrus essential oils tend to be more reactive to their environment and therefore the shelf life of these oils is often among the shortest when compared to other essential oils. Keeping them in a dark, cool place, even the refrigerator, can help to lengthen this time and preserve their aroma and therapeutic properties for longer.
Citrus essential oils all contain varying proportions of a class of chemicals known as furocoumarins which can cause phototoxicity. This is the phenomenon whereby skin on which the essential oil has been applied becomes more sensitive to sunlight and can be more likely to burn when exposed to the sun. Furocoumarins are more usually found in citrus oils as the chemicals are not usually found in any great quantity in distilled oils. Although many warnings about essential oil phototoxicity encompass all citrus essential oils equally, in fact different citrus essential oils will contain different levels of furocoumarins and therefore also have different phototoxic effects. Essential oils such as bergamot (containing bergaptene) are amongst the most reactive, whereas others such as sweet orange are considered the most safe. Sweet orange is stated by some to not have any risk of phototoxicity, although there are reports of people having apparent phototoxic reactions from some brands of sweet orange. Although whether those reactions are due to misidentifying of the oil, contamination, or some other factor is not clear. So although citrus essential oils do not all carry the same risk, some advise to treat them all the same due for ease of reference.
Citrus essential oils have different properties, but do share some common characteristics of being uplifting to the mind and to the emotions.
A word of caution –
One of the most common misuses of citrus essential oils is in believeing that they can be substituted for the juice of the corresponding fruit in food and drink. This is usually due to a misunderstanding of the differences between the two substances or of how citrus essential oils are made. Adding juice to a drink for example is fine as the juice is water soluble. However the essential oil is not water soluble and so adding this to a glass of water can be quite dangerous (Read more about using essential oils in food in this blog post.)
Let’s look at some of the most common Citrus Essential Oils –
Extracted from the peel of a small yellowish citrus fruit, Bergamot derives its name from the City of Bergamo in Italy. Opinion is divided as the pronunciation of the common name with some pronouncing the ‘T” and some leaving it silent. (I was first exposed to the oil with the ‘T’ so I subscribe to the first pronunciation.)
Bergamot is used to produce the distinctive flavour of Earl Grey Tea. It is also popular in perfumery.
I like to incorporate Bergamot Essential Oil in any blend for stress related conditions due to its relaxing and de-stressing properties.
A relative newcomer to the citrus family, the grapefruit most likely originated from a hybrid of sweet orange and Pomelo (also known as Shaddock) in the West Indies.
It became a popular breakfast fruit in various parts of the world. Originally thought to be too sour, newer cultivars have given us not only yellow grapefruit but also pink and red varieties whose fruit is generally sweeter.
Grapefruit became a popular “diet food” due to the original yellow variety being lower in sugar than other grapefruit varieties or other sweet citruses.
I find Grapefruit Essential Oil to be very refreshing and useful for stress and fatigue. Its astringent action also makes it useful for oily or congested skin.
Lemons have been around for so long that their origin is somewhat obscure. However they are thought to originate in Asia, being brought to the middle east and then to Europe during the time of the Crusades.
Lemons are widely used in foods and drinks, from savoury and sweet dishes through to drinks such as lemonade or being added to tea.
Lemon essential oil is fresh and invigorating and I find it helpful for mental fatigue, concentration (I like to add it to study blends) and also for oily skin.
The lime was introduced to Europe around the same time as the lemon and with many similar uses. Both lemons and limes were utilised by British sailors to help prevent scurvy – the vitamin C content prevents this disease – leading to the nickname of “limeys” for British sailors.
Limes produce a sweeter smelling essential oil than lemon – although still with a fresh clean aroma. It is popular in perfumery as well as in foods and drinks.
I use Lime essential oil for its refreshing properties, especially when I am looking for something softer than Lemon.
Mandarins are thought to be one of the oldest species of citrus, originating in Asia. In China they are considered to be a symbol of good fortune making them a popular gift during Chinese New Year.
Mandarins are a popular food for both adults and children, being both sweet and very easy to peel.
Mandarin essential oil is uplifting but also calming making it a perfect essential oil for children
The sweet orange originated in South-East Asia in ancient times and gradually became popular through the middle east, North Africa and Europe. The botanical name “sinensis” is Latin meaning “from China”
The juice of the orange has become a widely consumed drink, adding to its popularity.
Sweet orange is one of the cheapest and easily obtained essential oils. It also marries well with many other essential oils, adding a touch of sweetness to a blend. It has a sunny character, useful for uplifting the spirits.
(Note – Orange sweet should not be confused with the Bitter Orange, Citrus aurantium amara, which also produces the distilled essential oils of Petitgrain (from the leaves) and Neroli (from the flowers)
Explore the wonderful world of Citrus Essential Oils and share your favourites in the comments!