Expert: Terry Knorr - 8/23/2004

Question
How do I keep my soap from sweating after it is made?

Answer
Hi Candice.

This is a very common problem which you are experiancing.  Glycerine is a by-product of soapmaking.  All soaps contain glycerine (approx. 25%, by weight), unless it is removed.  Your soap sweats because the glycerine attracts moisture from the air.  You can prevent the sweating in 2 ways:  remove the glycerine or a portion of it, or block the moisture from contacting the soap.  

The glycerine can be removed by adding a small amount of Sodium Chloride (table salt) to your formula.  During the soapmaking process, the glycerine will seperate from the soap.  A small amount of the glycercine can then be put back in, if desired.  However, because I don't like to remove the glycerine from my soaps, I do not know how much sodium chloride to add.   If you decide to go this route, I'd be glad to research that for you.

I choose to block the moisture from my soap.  I shrink wrap all of my soaps using preformed PVC bags, and keep them in a cool, dry, and dark location for storage. This has the added effect of holding in any essential oils or scents used in your soaps.

I hope this will give you the information you need.   However, if you need more, don't hesitate to contact me again!

Happy soapmaking!
Terry