The washing nut tree (
Sapindus mukorossi), is one of the most important trees in tropical and sub-tropical regions of Asia. The most priceless part of the tree are its fruits, having been used for washing for many centuries. The plant grows wild from Afghanistan to China, prefers deep loamy soil and in areas with a yearly rainfall of 1500 to 2000 mm.
Washing nut trees can live for over 80 years, reach a height of 24 metres and a circumference of up to 5 metres. The bark is light-gray and smooth in young trees, dark-gray in older ones.
The tree carries the first fruit after 10 years: orange, sticky nuts, similar to hazelnuts in size and harvested in September. After being dried the fruit is not sticky anymore and turn sred-brown to dark brown.
The paring of the nuts contains up to 15% saponin, whereby the quality depends on the harvest and the tree's age.
Washing nuts The nuts are opened for washing, the black core is removed and the paring placed in a small cotton bag (or an old sock) for washing. Depending on the washing temperature and water hardness, the amount varies from 3 to 7 hut halves.
The washing nuts can be used for at least 2 times in washing processes of up to 40 °C. The rest can be composted afterwards. Depending on the water hardness, one should add a water softener. Alternatively, the washing solution can be acidified with citric acid because saponin glycoside is also effective in an acidic solution. Washing nuts contain no perfume, therefore one can use a few drops of an essential oil (lavender, lemon, verbena) instead of a fabric softener. The wash will be scented as desired.
As a shower gel or a shampoo, one cooks a few washing nuts in water and fills the brew in a bottle. The washing nut brew can also be used as a multi purpose cleaner in the house.
On 24 March 2006, ProSieben tested washing nuts against a convential washing agent in the Infotainment programme "Galileo". The test result was that washing nuts removed hard stains up to 100% and therefore is better than normal washing agents. The wash was soft without a softener. Even the presentation of the washing nuts on 4 September 2007 in the programme "Planet Wissen" showed that they can replace conventional washing agents in many cases. The wash is cleaner and a softener is not necessary.
The active components of the washing nut can also be applied during the end phase of the cleaning process and hence, not completely washed out. This depends on the fact that the washing nuts remain constantly in a bag and the washing substances are permanently released. However, this fact is completely harmless due to the biological compatibility of the washing nuts.
It is also interesting the the water extract from the washing nuts' paring has an affect against various phytopathogenic fungi.
Application of the Washing NutsThe fruit is traditionally used for washing clothes and hair in India, but also in the Chinese and Ayurveda medicine.
