I first encountered this unusual fruit whilst lecturing in Japan, and was immediately captivated by its distinctive fragrance. I decided I must learn more about this little-known member of the citrus family and see if it might prove a useful addition to aromatherapy.
Several trips to Japan later, I finally tracked down a producer of this fragrant fruit and arranged to purchase some of the essential oil on a regular basis. Sadly, the essential oil is not produced in very large quantities which therefore makes it quite expensive for a citrus oil, and very difficult to purchase other than directly from source.
From the Rutaceae family, Citrus junos bears a physical resemblance to the bitter orange tree (Citrus aurantium ssp amara), reaching a height of approximately 4 metres (13ft). It has a rounded top of deep green, smooth, oval shaped leaves and attractive white flowers which bloom in early autumn.
In Japan during the late autumn, the small fruits ripen from dark green to a yellow-golden colour, and now resemble oranges which measure about 7.0 cm (2¾ inches) in diameter. The peel is much less smooth than that of an orange, often having a more 'pitted' and 'bumpy' appearance. Interestingly, yuzu is one of the most cold resistant citrus fruits.
Current and traditional uses
Both the fruit-juice and the rind of yuzu are extremely popular as flavouring agents in Japan, imparting an absolutely delicious, lemon-fruity and floral tang wherever it is employed. It is used to make a refreshing lemonade-type beverage, blended in salad dressings, made into marmalade and is even employed in ice-cream (my favourite!). In fact there seems to be no end of ways the Japanese have found to utilise the rind of this delicious fruit!
Traditionally, the fruits were used in a hot bath on the day of the winter solstice (Toji) to ward off a range of winter ills, such as colds and flu. To make a 'Yuzu yu' (Yuzu bath), the whole fruits or just the peel are added to the hot bathtub, and just as in aromatherapy, a nice long relaxing soak would bring about a feeling of wellbeing.
Of course, yuzu baths can be enjoyed at anytime for other conditions such as arthritis, rheumatism and general aches and pains. The oil from the fruit produces a tonic effect that stimulates the circulatory system and digestive system.
Although Citrus junos grows wild in Tibet and Korea, it is believed to have originated in China and was brought to Japan for cultivation in the 10th century. Due to its popularity here, it is cultivated on a grand commercial scale especially in Kochi Prefecture on the island of Shikoku, where large yuzu groves can be found.
Curiously, these other countries do not appear to produce the essential oil in very large commercial quantities, and despite many attempts I have been unable to locate producers of yuzu oil who are interested in exporting the oil. This is a pity, since it would be fascinating to compare the oils produced from the different origins.
Extraction and aromatherapy uses
The essential oil is extracted by cold expression of the rind, producing a pale yellow essential oil with an exquisite citrus aroma. This body of this fragrance exists somewhere between grapefruit and mandarin, with subtle overtones of bergamot and lime. It has a very dry, tangy quality whilst producing an almost floral note that is very appealing.
Used in aromatherapy, we have found that yuzu oil is very similar in action to bergamot, having a refreshing and uplifting effect on the body whilst calming the mind. Also in common with bergamot, this oil has a powerful anti-bacterial action which makes it effective against colds and flu, which would account for its success and popularity in Japanese folk medicine.
It is a very effective oil for use with stress, burn-out, nervous tension or anxiety, where it helps to bring a soothing and calming effect to the emotions. Likewise it gives upliftment to depressive states, frustration, regret and also helps to build confidence.
As you might expect, yuzu blends easily with all citrus oils, although to do so simply dilutes its unique fragrance. Try blending it instead with basil, benzoin, clary sage, chamomile Roman, cypress, frankincense, geranium, ginger, jasmine, juniper berry, lavender, neroli, patchouli, petitgrain, rose (absolute & otto), sandalwood, vetiver and ylang ylang.
I find yuzu a very intriguing and rewarding oil to use, and hope that more will soon be discovered about its therapeutic properties. After a long and stressful day, I find it really gives a welcome boost to both mind and body. Try yuzu yourself, and see if you don't agree it is the king of all citrus oils.