How to - Soapnut Decoction

You're already an old pro at making a decoction from the earlier post where we made one with soaproot, so let's jump straight into making a decoction with soapnuts (also called soap berries). If you're curious to know a bit more about soapnuts, check the links at the bottom of this post.

The method is quite similar, but there are a few soapnut-specific tips to be had, so let's go through the process step by step.

Tools and Ingredients

  • Soapnuts 
  • Large tea filters (the size used to make an entire pot of tea)
  • Demineralised water
  • Broad spectrum preservative (absolutely mandatory!)
  • Scale
  • Coffee filters (or clean cheesecloth)
  • Container for your deconcoction
  • Saucepan with well-fitting lid (no aluminium!)
  • PH-test strips (optional for some, but I cannot do without)


1. Be sure ALL of your equipment is clean/sterile

2. Measure out 500ml of water

3. Weigh out 25 gr of soapnuts (this is approximately 12-15 soapnuts)

4. Place soapnuts into 2 tea filter bags and staple shut

5. Pop the bags into your saucepan

6. Add water

7. Add preservative accordingly (the amount, type, and when to add depends on the preservative you use)

Since You Ask...

A few of you have asked me which preservatives I use for decoctions and if it is ok to use X or Y preservative.

My personal fave and the combo that has never failed (for infusions, decoctions, hydrosol-based lotions, creams and a number of other products) is a mix of phenoexethynol, ethylparaben and methylparaben.

A similar combo (also broad spectrum) is sold by many cosmetics suppliers under the name Phenonip.

On with decocting...

8. Pop lid on

9. Bring to a boil, then reduce the heat immediately

10. Let simmer 20-30 minutes

11. Strain the mixture through a coffee filter

12. (extra soapnut-specific tip) Squeeze the bags to extract as much liquid as possible. Here, I used a spoon to mash the bags against the side of the pan.

13. Bottle

14. Do a pH test

The pH of this soapnut decoction is 4.5.
The soaproot decoction from the other day had a somewhat higher pH: 5.7

15. Rejoice and enjoy all the soapiness you just made!

This batch started as 500ml with a final yield of 420 ml.

Next up: We're going to take a comparative look at our 2 decoctions

A Bit About Natural Surfactants From This Blog

Doing Laundry with soapnuts


Wendy said…
Hi Lisa,
Thanks for your post on this topic. I imagine this can be mad using soap nut (Aritha) powder. If so, how many grams of powder would you use? Thanks,
LisaLise said…
Hi Wendy - great question! I have never worked with soap nut in powder form, so I'm guessing it is 'merely' dried and powdered soap nuts and they do not dissolve completely in water. If this is the case, then I would suggest using 25 grams of the powder. It is in any case a question of how concentrated you want the final mixture to be.
Parita said…
I have been using sopanut concotion since yrs now and swear by it but I usually just boil few soapnuts in water and squeeze out the juice everytime I wash my hair..i know a bit tedious but works for me :)
Where do you buy soapnuts from? When I was in India they were easily available not sure where to find them here in the US?
LisaLise said…
Hi Parita - in the US, check with Mountain Rose Herbs - I believe they carry both soap nuts and soapwort
Unknown said…
Hi Lise

Thank you for this post. I have now made this decoction. I made a vanishing cream on this basis which works like a beautiful cleanser which can be washed off with water rather than a cloth. I am obsessed with the result, considering how new I am to the whole DIY skincare.

Thank you for your insights!!

My inspiration was Niod Sanskrit Saponins cleanser.

Here is my formula as a thank you (you probably have thousands of your own, but I am superhappy with this one).

Saponins cleansing cream

Stearic acid 22,50% 45
Triethanolamine 1,50% 3
Potassium hydroxide 1% 2
Glycerin 5% 10
Soapnut water 68% 136,4
citric acid 1% 1,6
Phenoxyethanol 0,5% 1
Potassium sorbate 0,5% 1
100,00% 200

Mix phenoxyethanol with glycerin
mix potassium sorbate with a a little soapnut water just to dissolve it, set aside

add stearic acid to soapnut water. Hit up in a water bath until melted.

once melted, add triethanolamine and mix.

add potassium sorbate, mix.

CHeck PH. Add Citric acid. check PH again (should be in a range of 6 or so).

Add the rest.

Essential oils (sorry, I still measure in drops)

grapefruit 27 sweet orange 6 patchuli 2 cedarwood 24
LisaLise said…
Hello Natasha and thank you kindly for sharing this lovely formula. I am always thrilled when people take the time to let me know if I have inspired them. I will be running around with a big smile on my face all day thanks to you. :D