First Attempt at Soap (hot process, well-used fry oil, sour milk)

[JakeBlanton]

I wanted to try to make some soap from some old used cooking oil that I had saved. Just a low cost (i.e. just the cost of the lye) experiment to see what would happen. I normally just mix a bit of this with my dogs' dry dog food as a treat, but since I had it, I was curious what would happen if I tried to make soap from it. I had 482 g of this very well used (i.e. black) oil. I also had 303 g of some milk that had gone sour.

Running this through the soap calculator (assuming 50% soybean oil and 50% canola oil) resulted in a suggested lye weight of 61.54 g and 183.16 g of water. So, I used 62 g of lye and 183 g of the sour milk.

I heated it in a crock pot, stirring with a stick blender until it got too thick to use the stick blender anymore. It's a 500W stick blender, so it had plenty of power, but the mixture got thick enough that the stick blender blades would just cavitate instead of moving the material around. I allowed it to volcano 3 times, stirring it down each time it reached the upper edge of the crock pot. Total time was about 90 minutes. A dash of Pine-Sol was added as a fragrance at the end. I doubt it will make much of a difference though. The rest of the sour milk was also added between volcano #2 and #3. The crock pot was on high during the entire process.

It hasn't cooled off / solidified yet, but when I was cleaning the utensils and crock pot with water, it most definitely felt like soap. While cooking it, there was a smell of fried corn meal in the house, but I could not smell it in the soap. That might just be because my nose had become de-synthesized to the smell during the cooking process. I also don't smell the Pine-Sol.

For a mold, I used a plastic shopping bag lined Pyrex bread loaf baking dish.

Mainly, I wanted to do this so that I could see the stages that the soap goes through during the cooking process and to see if it was possible to have a use for very old fry oil and sour milk. Figured it might be an interesting experiment. I'll post photos after it has cooled off and hardened.

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[Kcryss]

Wow, I guess I shouldn't feel bad anymore about 1.5 cook time. Maybe it's not just me?
Interesting experiment. I wonder if it will develop DOS or smell off during/after cure?

 

[JakeBlanton]

It was a small enough batch and a tall enough crock pot (one of the old ones where the ceramic pot is not removable -- probably 30+ years old) that even though it had a very well developed volcano, it was just barely starting to show over the top and could easily be stirred down. Since the soap is just for my own use, I'm not concerned about any cosmetic imperfections in it. My eventual goal is to develop an abrasive soap that is even better than Lava for cleaning grease off my hands after working in my workshop or on my car.

 

[Kcryss]

It was a small enough batch and a tall enough crock pot (one of the old ones where the ceramic pot is not removable -- probably 30 years old) that even though it had a very well developed volcano, it was just barely starting to show over the top and could easily be stirred down. Since the soap is just for my own use, I'm not concerned about any cosmetic imperfections in it. My eventual goal is to develop a soap that is even better than Lava for cleaning grease off my hands after working in my workshop or on my car.

Makes sense. I'm working on one for my son in law for the same reason. I want to add pumice, finely grated orange peel and will probably use enough CO to get it up to about a 20 on cleansing. He's tried my other soaps and they work pretty well for his greasy hands, but I think he would be happier with something a bit stronger and manlier.

 

[Obsidian]

I use 30% coconut oil for a greasy man soap. Its too harsh for me but works great for hubby, even when he is covered in hydraulic fluid.

 

[JakeBlanton]

Makes sense. I'm working on one for my son in law for the same reason. I want to add pumice, finely grated orange peel and will probably use enough CO to get it up to about a 20 on cleansing. He's tried my other soaps and they work pretty well for his greasy hands, but I think he would be happier with something a bit stronger and manlier.

I'm thinking using aluminum oxide blast media as the abrasive in the soap once it cools down and before I put it in the mold. That is harder than pumice and is fairly cheap in that I can pick it up at Harbor Freight for $45 for a 50 lb bag. Of course, if you don't also have another use for it, then that 50 lbs of media would end up making a LOT of soap. If the soap was only going to be used outside, using sand as an abrasive might also work.

 

[Kcryss]

I'm thinking using aluminum oxide blast media as the abrasive in the soap once it cools down and before I put it in the mold. That is harder than pumice and is fairly cheap in that I can pick it up at Harbor Freight for $45 for a 50 lb bag. Of course, if you don't also have another use for it, then that 50 lbs of media would end up making a LOT of soap. If the soap was only going to be used outside, using sand as an abrasive might also work.

Hmm ... sounds interesting. I'm thinking ground shredded coconut or finely ground orange/lemon peels would be cheap. Especially if you eat oranges. Just shred and dry, then grind them up.

 

[JakeBlanton]

Hmm ... sounds interesting. I'm thinking ground shredded coconut or finely ground orange/lemon peels would be cheap. Especially if you eat oranges. Just shred and dry, then grind them up.

Just started my second batch using fresh (unused) oil and water... 500g oil (soybean assumed since I don't remember what it was when I bought it and transferred it to 2-liter containers), 190g water (tap), and 65g of lye. The oil didn't seem very warm when I added the water+NaOH to it, but I then realized that the crock pot was not plugged in, so I reset my timer to see how long it takes.

 

[Obsidian]

No, do not use aluminum oxide in your soap. Aluminum and lye causes a dangerous chemical reaction not to mention it simply will be too scatchy. You want your skin left intact.
Get some ground pumice from a soap company, it really isn't that expensive. You can also use coffee grinds for scrubby. I've found the finer turkish grind works well without being too harsh.

And please for the love of God, don't use pine sol or other cleaners for scent. These things just aren't made for use on skin, could cause a bad reaction.

If you want to make soap, you really need to stick with additives that are skin safe.

 

[JakeBlanton]

No, do not use aluminum oxide in your soap. Aluminum and lye causes a dangerous chemical reaction not to mention it simply will be too scatchy. You want your skin left intact.
Get some ground pumice from a soap company, it really isn't that expensive. You can also use coffee grinds for scrubby. I've found the finer turkish grind works well without being too harsh.

And please for the love of God, don't use pine sol or other cleaners for scent. These things just aren't made for use on skin, could cause a bad reaction.

If you want to make soap, you really need to stick with additives that are skin safe.

This is for my own use, not to sell. I've cleaned things with Pine-Sol (in its various incantations) for over 50 years, so I'm not too worried about its affect on my skin. And I am actually wanting something *more* abrasive than pumice. At these temperatures, aluminum oxide should be be reactive.

Here's what they look like taken out of the mold (probably before they had time to solidify) and cut up...

 

[KiwiMoose]

@JakeBlanton Aluminium and lye are not friends. Do not use them together.
You can use sand - I have done so in the past. Unfortunately was too fine (finer than the pumice) so not too scrubby. Try to get a fairly coarse sand if you can - that might satisfy your scrub factor requirements.

 

[JakeBlanton]

The first (darker) batch still seemed a bit soft today, so I reheated it in a double boiler and let it cook for awhile. Added a dash of salt to it also. It seems a bit harder now. I've put it under a fan to hopefully speed up the drying process. The "double boiler" was actually a stainless steel bowl that fit in the top of a 2-qt pot. I used that because it is easier to clean than the crock pot since the crock pot does not have a removable inner portion. There is just a very light Pine-Sol smell from the soap and no noticeable smell from the old well used fry oil.

 

[MGM]

TBH, I find coffee grounds more abrasive than pumice or sand. They end up being quite scrubby if you use enough. Poppy seeds, too.

 

[amd]

My next door chemist also agrees, do not use aluminum oxide with sodium hydroxide, the two will react regardless of the temperature. Also... he says if you like having skin on your body, don't use it in this form. There is a form of aluminum oxide used in microdermabrasion - but it is treated and refined, but still would not be suitable in a lye based soap. I agree with his assessment, there are many other things that work just as well as exfoliants that won't cause damage to your skin or negative chemical reactions.

Please, stop free lancing your experiments until you've gotten a good handle on soapmaking practices, and considerable more research into what you are doing. This type of sharing doesn't benefit other new soapmakers who also come here for advice. Please don't put pinesol in soap intended to be used on skin, I don't particularly care if you are selling or not, it's not something you want to expose your entire body to day after day, unlike normal cleaning practices where you have limited body exposure (hands if you don't wear gloves) and infrequent exposure - once a week I hear is a normal cleaning routine.

 

[GML]

I see someone fell down the YouTube soap making rabbit hole...

 

[Sharyn]

Hahahahaha, absolutely, been doing it a little while now, about 3 months. Just loving it! Learning a lot from this forum.

 

[JakeBlanton]

My next door chemist also agrees, do not use aluminum oxide with sodium hydroxide, the two will react regardless of the temperature. Also... he says if you like having skin on your body, don't use it in this form. There is a form of aluminum oxide used in microdermabrasion - but it is treated and refined, but still would not be suitable in a lye based soap. I agree with his assessment, there are many other things that work just as well as exfoliants that won't cause damage to your skin or negative chemical reactions.

Please, stop free lancing your experiments until you've gotten a good handle on soapmaking practices, and considerable more research into what you are doing. This type of sharing doesn't benefit other new soapmakers who also come here for advice. Please don't put pinesol in soap intended to be used on skin, I don't particularly care if you are selling or not, it's not something you want to expose your entire body to day after day, unlike normal cleaning practices where you have limited body exposure (hands if you don't wear gloves) and infrequent exposure - once a week I hear is a normal cleaning routine.

It's not a body soap... Strictly for removing grease and such that has turned my hands black while working on things in my workshop or garage. And a dash of Pine-Sol smells a lot better than the gasoline that we used to use to clean the grease off our hands.

And I disagree with whether it helps others... Finding out how to NOT do things is helpful...

The used fry oil batch never really seemed to harden up as hard as I would have preferred, even with a fan blowing on it. So, I decided to experiment with it a bit... I was thinking that maybe I just had too much oil for it to really harden, so I decided to add a bit more of a base to convert the oil. I decided to try some quicklime instead of lye. This seemed to get slightly harder, but not to the level that I thought it should be at. It also left the bars with a bit of what seemed like oil (maybe glycerin?) dripping out of it... Maybe I should have used the stick blender to incorporate it into the melt instead of just stirring it in? So, I was reading on the web and saw where someone had used rice flour in a soap recipe and decided to try that to see what would happen. Since my end goal in all of this was an abrasive soap for cleaning my hands after working in my garage, instead of rice flour, I just used the stick blender to grind up about 1/2 cup of dry / uncooked rice into fairly small granules (but definitely NOT powder / flour) and then stirred it in. That seems to have made a difference. Even after just a few hours, the soap is harder than the previous attempts were after a couple of days. Whether the rice granules will be abrasive enough for my intended use is an entirely different question though. I remember that some people do use uncooked rice in vibratory tumblers for cartridge brass cleaning instead of the traditional corn cob media.

 

[GML]

I'm curious, did you develop a recipe or did you just decide to wing it? I'd suggest that maybe you take a breath, do some research and then try again.
FYI, a scrubby soap that I've made before consists of ground coffee, ground oats and dried orange peel. You can add the coffee ground dry to the batter for extra scrubbing action).

 

[JakeBlanton]

I'm curious, did you develop a recipe or did you just decide to wing it? I'd suggest that maybe you take a breath, do some research and then try again.
FYI, a scrubby soap that I've made before consists of ground coffee, ground oats and dried orange peel. You can add the coffee ground dry to the batter for extra scrubbing action).

It started out as a recipe... At least as much of a recipe as you can have when you are not entirely sure what oils are in the used fry oil -- probably soybean, cottonseed, corn, canola, and various animal fats... From there, it became more of wing it thing to see what would happen if different things got added to it since I did not consider the first iteration as hard enough for a hand soap. It only got to about fudge type hardness initially. If I had never achieved a hard soap, it would not be a deal breaker though. Since it was just for my own use for cleaning grease and such off my hands, I could just cast it into a large open top container and rub my hand across the top of it when I needed to wash my hands. Kind of somewhere between a liquid and a bar soap, I guess...

The 2nd batch that I made with a single vegetable oil hardened up noticeably better, although since I didn't know what type of vegetable oil it was, I might not have had enough lye. Regardless, it worked and my wife seems to like the way it makes her skin feel -- she tends to have dry skin and normally ends up putting tons of lotions on after a shower.

 

[Sony Sasankan]

Since my end goal in all of this was an abrasive soap for cleaning my hands after working in my garage, instead of rice flour, I just used the stick blender to grind up about 1/2 cup of dry / uncooked rice into fairly small granules (but definitely NOT powder / flour) and then stirred it in. That seems to have made a difference.

Interesting Experiment. Since you were doing HP, I assumed the rice would cook itself with all that extra water and soften itself. So the cracked rice remained hard and effective as an abrasive? Did you add the rice last after the cook (with the pine-sol)?