Sugar & salt in soap - what type & when or where to add

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Well-Known Member
Aug 5, 2014
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I've seen a few threads about adding sugar and salt to soap. For those who don't know sugar is supposed to make for better lather and salt is supposed to help harden the bar.

What I would like to know is what you add, when you add it, what mix you add it in and what ingredient you use.

My first experience was with powdered sugar (which has a very little bit of corn starch to prevent clumping) which was added to my lye mixture (which was a coffee concentrate w/ lye added). The sugar was mixed in at about 90 degrees F and it seemed to dissolve completely (but was hard to see in the dark liquid). I added 28g per KG of oil

I read that some add the sugar to the oil mix which I tried to disastrous results. I used regular table sugar, 28g/KG oil and added it to the hard fats which were heated - then added sugar. It does not dissolve from what I could see. I heated hoping it would dissolve but it seemed to caramelize and congeal instead. I filtered the oil to remove the sugar and saved the batch.

I then tried adding the sugar to the lye water, table sugar, and this did not work well either. The water was about 110 degrees and the sugar formed a clump that was the texture of maybe silly-putty (but with granular texture). With a long time of stirring, 5 minutes, 10 off, repeat for 2 hours, it finally dissolved (86 grams). I also tried adding 2 grams of powdered sugar and it formed lots of floating globs of what looked like a plasticy mixture - which I ended up skimming off. In the end I filtered the lye mix through an old cotton tee-shirt and then a coffee filter. A layer was slowly formed on the filter material that was almost plasticy or like a crystallized sugar coating - but it did finally filter.

From my experience I think what I will be doing in the future is withhold 5-10% of the water when making the lye mixture and use this water to dissolve the sugar. Once dissolved (both the lye & sugar) I will mix the two water mixes and see what happens.

I'd like to know how you get your sugars into the mixtures.

I've considered some other types of sugar such as:
Honey (glucose & fructose)
Corn syrup (glucose syrup
High Fructose Corn Syrup (HFCS)
Mannitol - sugar alcohol - C6H8(OH)6
Xylitol - sugar alcohol - C5H12O5
raw sugar (sucrose - unbleached)
Sucrose - (cane/beet sugar, table sugar or powdered - C12H22O11)
Glucose (Grape sugar - Dextrose - C6H12O6)
Fructose - fruit sugar - (C6H12O6)

From what I've read salt should be added in about the same amounts of sugar, or lesser amounts if you desire a softer bar. I suspect that it could be added in the same way that the sugar is added. The only question is what kind of salt to use.

Normal table salt is NaCl (sodium chloride) and most has iodine added. IDK if un-iodized would be preferable. Another option is KCl (potassium chloride). I've heard that KOH is preferred in making softer soaps so if the goal is to harden the bar it may be wise to stay with the NaCl (as NaOH makes harder soaps). What are thoughts on this? What are the amounts you use and when do you add it?
I save out a ounce or two of water to dissolve plain white sugar in, this is added once the lye/oils are mixed. for the salt, I dissolve it in the main water before adding the lye. I use 2 tsp PPO with both sugar and salt.
I haven't used any other sugar except honey and I really don't care for it. Regular white sugar boosts bubbles without adding any color and thats what I want.

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