How do I add glycerin or goats milk to CP?

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fafu808

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Hi there. I've searched for a few threads on this subject but could not find a specific answer. My friend and I are going to make our first batch of soap soon. The only reason I'm helping is because I dont feel comfortable with her handling sodium hydroxide. From what I understand that crap melts flesh, and being a bro my skins less important than hers haha.

I was wondering how we'd add vegetable glycerin to soap. I know sodium hydroxide and your oils makes glycerin but we'd like to add our own vegetable glycerin. I'm assuming that vege glycerin does not saponify (I could be totally wrong, and it'd be dangerous to make soap based on assumptions) and we're not looking to do that thing where you add the vege glycerin after the sodium hydroxide and oils have traced. We'd like to use more than that. I'm assuming that when you list ingredients for your soap you sell, you do it from the biggest quantity to the least, and if you were adding the glycerin after trace, I'd have to assume it'd be a very small amount of your soap, but I've seen soaps where glycerin is one of the first 5 ingredients, and its cold process soap, not melt and pour.

Also when making goats milk soap I've read you can substitute the water from your water/sodium hydroxide solution with goats milk. Is it possible to do 50/50 water and goats milk when you mix it with the sodium hydroxide? Or do you have to make it 100% goats milk?

Any help is appreciated! I'm sorry if I sound like a total scrub, I've yet to make my first batch :/ All of our ingredients and supplies are coming in around New Years :)
 
You can use goatsmilk in any percent you want. A 50/50 mix will work well, make sure its really cold and mix your lye into it slow so it doesn't overheat. It will smell bad, don't be turned off by that.

While lye will burn if you get it on your skin, it won't melt your flesh. Where rubber gloves like what doctors use to protect your hands. If you get any lye or soap batter on your skin, wash it off and use straight vinegar to neutralize the lye.

You can add glycerin at trace or straight into your oils. I really wouldn't add more then a teaspoon or two per pound of oil though, too much will make your soap soft or sticky.
The soap you see with glycerin listed in the first few ingredients are either melt and pour or they have listed the ingredients in the wrong order. Any reason you want to add a lot?
 
You can add glycerin at trace or straight into your oils. I really wouldn't add more then a teaspoon or two per pound of oil though, too much will make your soap soft or sticky.
The soap you see with glycerin listed in the first few ingredients are either melt and pour or they have listed the ingredients in the wrong order. Any reason you want to add a lot?

Thanks for the reply :D My friend has a bunch of left over vegetable glycerin that she was using to make other products. I guess it'd be best to just a little bit after trace then right? After the oils trace, does adding a small amount of sweet almond oil, macadamia nut oil, and vege glycerin sound good? How much do I add after trace. Is it per pound of soap or per pound of base oils that I use? How do I calculate how many pounds my soap will be if I'm adding the extra oils per pound of soap?
 
You can use all goat's milk. My suggestion is to freeze the goat's milk in ice cube trays first and then add the lye just a little at a time while stirring constantly. You have to make sure that the lye is all dissolved, I usually strain the lye solution into the oils, that way there are no dissolved lye particles in the soap. Good luck on your first batch. By the way glycerin is a bi-product of soap making so as obsidian stated, don't add very much. Instead I would use oils that are high in unspaonifiables like shea butter, (maximum usage rate 15%), avocado oil, (maximum usage rate 30%) and pomace olive oil along with some coconut (maximum usage rate 30%), and Castor oils (I use about 5%).
 
Adding extra oils after trace doesn't add anything to your soap as there is still active lye and it will saponify what it wants. The only way to choose what oil you want as a superfat is to make hot process soap.

Have you learned how to use a lye calculator yet? http://www.soapcalc.net/calc/soapcalcwp.asp is a really good one. If you are wanting a non drying soap, I would recommend setting the superfat at 8-10% for winter.
 
The only time I have added glycerin to my soap is for my shaving soap I CPHP in my crockpot. After the cook I put in the glycerin at about 1 to 1.5oz PPO as an added shaving benefit. I wouldn't use it in my regular CP soaps as it is already a product of saponification.
 
If you get any lye or soap batter on your skin, wash it off and use straight vinegar to neutralize the lye.

I wanted to clarify Obsidian's answer about washing lye off the skin. You want to rinse with a lot of cool water to rapidly dilute the lye. You don't want to use vinegar to rinse it off because the vinegar (acetic acid) will react with the lye and cause the lye to become even hotter. It can make a burn even worse. There was a discussion about this which goes into more detail. http://www.soapmakingforum.com/showthread.php?t=6735

Also, I agree with Candybee about it being unnecessary to add glycerin to CP batches. This is just my suggestion but you could try making glycerin liquid soap if you have glycerin you want to use up. Of course, you'd need potassium hydroxide instead of sodium hydroxide. Here's a link to one discussion about it. http://www.soapmakingforum.com/showthread.php?t=33468

Below is the video that inspired me to attempt making liquid soap with glycerin.

[ame]http://www.youtube.com/watch?v=o6brP--yQpU[/ame]
 
Adding extra oils after trace doesn't add anything to your soap as there is still active lye and it will saponify what it wants. The only way to choose what oil you want as a superfat is to make hot process soap.

Interesting folks, I guess I wont be adding any glycerin in. So you cant superfat in cold process?
 
This is the one that inspired me:

[ame]http://www.youtube.com/watch?v=3VUGV_H7bZU[/ame]

But you need to add about 3 oz water to the glycerin before adding the KOH(potassium hydroxide) which is different than NaOH(sodium hydroxide) that is sold as "Lye".

I will also add something to lye safety: wear long sleeved shirts with tight cuffs and a tight weave and safety goggles(not just glasses).

And make sure the container you mix the lye in is able to withstand HIGH temperatures! Test with BOILING water first. It has to be about 4 times as large as the water measurement. Taller is better than shorter containers.

You can superfat, but superfatting is adding more oil than the lye can saponify(turn to soap). Not adding extra oil at the end. I thought the same thing until someone told me differently.
 
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So you cant superfat in cold process?

Technically, you're using a lye discount in cold process. For 5% "superfat", you're only using 95% of the lye amount required for full saponification. This leaves 5% of the oil to remain unsaponified and be an emollient for the skin. There isn't any way to determine what oil or oils remain unsaponified in CP because the saponification process takes hours - it's usually stated as 24-48 hours. However, I have had batches in which I prevented gelling and they took days to saponify. The lye takes what it wants. However, there are oils which are high in unsaponifiables so it might be a good possibility these are part of the free oil in the soap. Examples of oils high in unsaponifiables are avocado, mango butter, unrefined shea butter, rice bran. I'm sure there are a few more but I can't think what they are right now.

In hot process, you're using heat to "cook" the soap through the gel phase and when it's done, it is soap. You can use 0% lye discount for hot process and then add extra oils after the cook for a superfat. You add enough oil for the percentage of superfat you want and because the batch is already saponified, you know for sure what oil remains for emolliency. Personally, I don't use 0% lye discount for HP. I use soapcalc.net to calculate the lye amount for the recipe and then keep out some of the oil I want to be the superfat (extra oil). For example, I would take out approximately 1.8 - 2.0 oz of the "superfat" oil in a 48 oz batch in which I had calculated a 5% lye discount, cook the batch and then add the oil back in at the end. This means I'm cooking the batch with about 1% - 1.5% lye discount. I add the FO or EO to the superfat oil which helps me not to forget to add the fragrance (which is something I've been known to forget :roll: ). Then I mix these into the batch after it has saponified.

eta: This is just the way I do it but it's not the only way. Everyone has their own method.
 
Wow, lots of great information. Thanks people!
How would I superfat with a specific oil in CP. Do I calculate the superfat to 0% and then add the specific oil I want to superfat with after I mixed the base oils and the lye water?
 
You can't pick which oil is your SF in CP, if you want to do that then you will need to HP instead. With CP, the lye is active for hours/days after its poured into the mold and it will eat up which ever oil it want, not what you desire.
If you HP, you cook the batter until the lye is used up then you add you SF oil of choice. I love avocado oil for a SF in HP.
 
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