Making homemade VCS (vanilla color stabilizer), called ZCS

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Todd Ziegler

Circle Z soaps
Sep 10, 2018
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Tipton IN
This is going to be a closed thread for the homemade version of commercial VCS (vanilla color stabilizer), which we are calling ZCS in order to distinguish between the homemade (ZCS) and commercial version (VCS).

10 ozs distilled water
3 ozs sodium metabisulfate (SM)
3 ozs sodium thiosulfate (pentahydrate) (STP)
There are two forms of the thiosulfate. One is a powder and the other is a crystal. Sometimes the seller leaves the pentahydrate description off. If the picture shows crystals you have the right one. If in doubt ask the seller. I have included a picture of the right one.

Safety precautions:
I suggest that you wear a mask and goggles. The mixture has a horrible sulfur smell and you don't want to get it in your eyes. These ingredients are skin safe and have been approved by the FDA for use in food and medicine but if you get any on your skin, just wash it off.

I suggest heating your water and it will make dissolving the ingredients faster but you don't have to. It will just take a while for it to dissolve but it will. Once your water is hot, pour it into the container with the ingredients and stir until dissolved. If the ingredients are dissolving slowly or the water gets cold just heat it back up.

I recommend that you make this ahead of time and do not make it one batch at a time. You can store it in either plastic/glass bottle but you need to make it airtight. I use a rubber stopper to keep the air out. You can use a natural cork or a liner underneath the cap but if you don't make it airtight it will crystallize and those crystals will make it unusable until they are dissolved again.

Usage rate:
It's recommended that you use this at a 1:1 rate to your FO.
(For example: if your recipe calls for 1oz of FO you would use 1oz ZCS to 1oz FO)
Add this directly to your warmed oils, and not your lye/water. Then mix it a little and now you can add your lye/water if that is your next step. (Always add it before you add your lye/water. And mix before adding your lye/water.)

1.If you add this to the FO directly and mix it, it will turn milky but it will just separate back out. It is still good to use. Just add it to your warmed oils and mix it.

2. If your FO has no vanillin but still discolors your soap, you can can add a little less than the 1:1 ratio. How much or little to add in this situation will come with experience but if you are not sure than use the 1:1 ratio to be safe.

3. WATER DISCOUNT, you can do a water discount if you want to but you don't have to. I personally don't because the extra amount of water has never affected my recipe adversely.


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