Bentonite Soap in Brine Soap & Humidity Issues


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Garden Gives Me Joy

Well-Known Member
Jan 25, 2020
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United States
My tropical rain forest climate is so highly humid that my soaps sweat profusely during wet seasons and a little less even in 'drier' periods sometimes. This is exacerbated when I do salt brine soap (where the brine is 25% of water). I am contemplating ordering bentonite clay for the first time with hopes of improving the soap experience for oily, acne prone skin. However, research suggests it is highly absorbent of water. What is the implication of using highly absorbent additives in soap?

Specifically, will it pose the threat of making water evaporation out of the soap even slower or more difficult?

Also, while I will soon have drying racks with ventilation and damp traps for each longer term storage draw, not everyone using my soap will have these things. So what are the risks if a friend without air conditioning or any other form of dehumidification opens the soap without using it immediately? I figure the soap will regain water weight it had previously lost in my space. Can water-attracting clay make ithe soap mushier than otherwise ... or more prone to mold if, God forbid, I make recipe variations with carbohydrates? What reasonable / non-burdensome instructions should I give people?

I welcome input regardless of the humidity levels of your location. I ifigure that I need to expect an exaggeration of whatever you experience in your drier climate.

Thanks in advance.


Supporting Member
Oct 30, 2018
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Bentonite clay has a very high water absorbency capacity. In soap it has caused a quick thick trace for me, I suppose it depends how much you use. If the design of the soap is simple it still works out. I have dispersed it in water prior.

I live in a place with high humidity (today is 56) but it is close to the 100's in the summer. However, every household has A/C here. My soaps do not usually sweat, but then again I use mostly hard oils and butter, not sure if that affects that. I use a 40% lye to water concentration too. It seems it might be best to do some experimenting in your local weather. Here is an article on bentonite clay compared to another one: