Liquid Goat Milk Soap

[cmzaha]

Looks like @DeeAnna covered most of your questions, @ackosel. I concur with her suggestion to use a 25% lye concentration to make the paste. It's much too hard to stir otherwise, and it will also be harder/slower to dilute.

Plus, the math is so easy with 25%. I use 1 part KOH dissolved in 1 part distilled water, then stir in 2 parts glycerin. The glycerin helps the batter to trace faster, and adds humectant properties to the final product.

Definitely 60% CO is on the high side, and I do like castor in LS, so I'd probably adjust that recipe to something like:

30% CO
30% Castor oil
20% Palm oil
20% OO or other HO liquid oil

There is lots of room for play in those ratios. If you know you like OO in LS, or don't have lots of castor on hand, then put the OO at 30% and the castor at 20%.

Since I have not used goat milk to make a liquid soap, I don't have any specific tips related to that, and I'll be quite interested to hear how that goes for you.

PS - I do make my LS at 0%SF, and so far, it's not been lye heavy, probably because my KOH isn't quite at 90% purity. But using 1-2% is probably safest for a first batch.

I will mention that I have had GM liquid soap go bad, so I recommend figuring out a preservative system for the pH of your liquid soap. If selling it, I would let it sit for several months and see how it holds. This is why I only used GM once in a batch of LS. In my opinion GM in soap does not do enough to hassle the issue with ensuring the preservative holds. I would go with pheno nip, but there may be better out today, I have not kept up with new products, but natural preservatives do not work well with gm.

 

[AliOop]

I will mention that I have had GM liquid soap go bad, so I recommend figuring out a preservative system for the pH of your liquid soap. If selling it, I would let it sit for several months and see how it holds. This is why I only used GM once in a batch of LS. In my opinion GM in soap does not do enough to hassle the issue with ensuring the preservative holds. I would go with pheno nip, but there may be better out today, I have not kept up with new products, but natural preservatives do not work well with gm.

Good info! I should clarify that I don't make GM liquid soap, and was just referring to the LS paste recipe and dilution.

 

[ackosel]

I will mention that I have had GM liquid soap go bad, so I recommend figuring out a preservative system for the pH of your liquid soap. If selling it, I would let it sit for several months and see how it holds. This is why I only used GM once in a batch of LS. In my opinion GM in soap does not do enough to hassle the issue with ensuring the preservative holds. I would go with pheno nip, but there may be better out today, I have not kept up with new products, but natural preservatives do not work well with gm.

That's interesting! I'm not selling it, so no worries there. I wonder what would make GMLS go bad? Is it not like bar soap where the ingredients cease to be oil, lye and liquid and become soap? Could the possible amount of milk fat in the 1% superfat be the cause?

My foamer bottles came today instead of Monday, so all I need to do is add more water to my dilution and give it a try!

 

[DeeAnna]

Soap is a source of fatty acids and water. A plate of just fat and water is a very unbalanced diet for microbes.

When you add a source of sugar and/or protein to the soap, you're creating a more balanced diet for microbes. A more balanced diet means it's more likely you'll see microbial growth.

To minimize the chance of microbial growth, you first want to (a) minimize the microbial contamination in the product (use sanitary manufacturing practices, choose packaging that minimizes user contamination, etc.) and you also want to (b) provide a starvation diet to discourage microbial growth (minimize additives that create a balanced diet, dilute only with water, etc.).

A preservative should be viewed only as a backup plan to mop up stragglers, not as a way to defeat a large, well-fed invading army.

KOH soap paste has a high pH and that functions pretty well as a preservative to discourage microbial growth, but once you dilute the paste into a liquid, you're reducing the protection offered by that high pH. A lot of times a diluted soap is just fine, but once you add stuff like milk, the situation gets a lot more "iffy".