# Can I make liquid soap? **URL:** \ **Category:** Factual Questions\ **Created:** [January 29, 2015, 7:28pm UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259 "2015-01-29T19:28:28Z")\ **Posts on this page:** 20\ **Page:** 1
**Author:** ![picunurse](https://avatars.discourse-cdn.com/v4/letter/p/7bcc69/32.png) [@picunurse](https://boards.straightdope.com/u/picunurse)\ **Post date:** [January 29, 2015, 7:28pm UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/1 "2015-01-29T19:28:28Z")
Can I make liquid soap from old bits and pieces of bar soap just by adding water in a sealed jar? I think I read that somewhere, so I put a bunch of little soaps, (My husband loves to bring stuff back when we stay in hotels, but, he never does anything with it.) in a sealable jar, then filled it with water. Now, two weeks later, the water is all absorbed into the soap, but it’s not liquid at all. I now have the biggest bar of gooey soap imaginable. Do I just keep adding water until I have the desired liquidity? ---
**Author:** ![Dorjan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dorjan/32/12440_2.png) [@Dorjan](https://boards.straightdope.com/u/Dorjan)\ **Post date:** [January 29, 2015, 7:39pm UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/2 "2015-01-29T19:39:07Z")
You need to add vegetable glycerin to keep it liquid. 1 tablespoon of glycerin/10 cups water / 1 cup of soap is a good ratio. You should also grate the soap to ensure maximum surface contact with the water and glycerin, you cant just put chunks of soap in the jar and expect it to work. ---
**Author:** ![picunurse](https://avatars.discourse-cdn.com/v4/letter/p/7bcc69/32.png) [@picunurse](https://boards.straightdope.com/u/picunurse)\ **Post date:** [January 29, 2015, 7:48pm UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/3 "2015-01-29T19:48:52Z")
> [@Dorjan](#): > > You need to add vegetable glycerin to keep it liquid. 1 tablespoon of glycerin/10 cups water / 1 cup of soap is a good ratio. You should also grate the soap to ensure maximum surface contact with the water and glycerin, you cant just put chunks of soap in the jar and expect it to work. Thank you, I’ll get some today. I guess, I’ll start over. Oh, can I put it in a food processor? I have an extra bowl and top. It’s all pretty soft now, so grating it is out of the question. ---
**Author:** ![am77494](https://avatars.discourse-cdn.com/v4/letter/a/d2c977/32.png) [@am77494](https://boards.straightdope.com/u/am77494)\ **Post date:** [January 29, 2015, 8:22pm UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/4 "2015-01-29T20:22:12Z")
> [@Dorjan](#): > > You need to add vegetable glycerin to keep it liquid. . Cite please ? I don’t believe what\*\* Dorjän\*\* said is true. Liquid soaps are made using potassium hydroxide as the alkali while solid soaps use sodium hydroxide. Adding water / glycerin will make it only more gooey - but it wont turn into liquid soap. From [Wikipedia](http://en.wikipedia.org/wiki/Soap#Liquid_soap): > [@](#): > > _The type of alkali metal used determines the kind of soap product. Sodium soaps, prepared from sodium hydroxide, are firm, whereas potassium soaps, derived from potassium hydroxide, are softer or often liquid_. ---
**Author:** ![purplehorseshoe](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/purplehorseshoe/32/2996_2.png) [@purplehorseshoe](https://boards.straightdope.com/u/purplehorseshoe)\ **Post date:** [January 29, 2015, 8:23pm UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/5 "2015-01-29T20:23:40Z")
> [@picunurse](#): > > Thank you, I’ll get some today. I guess, I’ll start over. Oh, can I put it in a food processor? I have an extra bowl and top. > It’s all pretty soft now, so grating it is out of the question. I’ve heard that you can give it a whizz in the blender if you prefer. Bonus: helluva clean blender! 😃 ---
**Author:** ![california\_jobcase](https://avatars.discourse-cdn.com/v4/letter/c/9d8465/32.png) [@california\_jobcase](https://boards.straightdope.com/u/california_jobcase)\ **Post date:** [January 29, 2015, 8:37pm UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/6 "2015-01-29T20:37:49Z")
The best thing to do with slivers of soap left over is to stick them onto the new bar of soap. Let it sit overnight, and the two will be one. No more wasting soap slivers! ---
**Author:** ![CraterLayer](https://avatars.discourse-cdn.com/v4/letter/c/87869e/32.png) [@CraterLayer](https://boards.straightdope.com/u/CraterLayer)\ **Post date:** [January 29, 2015, 8:59pm UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/7 "2015-01-29T20:59:22Z")
Soap has been one of my favorite interests since as a kid I saw Granny Clampett making it out of lye and hog fat in a big vat. I couldn’t figure out how grease and stuff that burns and the mafia uses to dispose of unwanted bodies could be the same stuff I wash my hands with, but when asked, my Mom said its true. Pass forward decades, I read a book that proposed that soap was one of humankind’s earliest discoveries. Here’s the gist of it: Imagine you’re an early human who just finished eating a wild boar that you cooked over your fire. your hands are really greasy, which bothers you. You could rub them in dirt, but that just makes them dirtier, as you have learned before. Or you could rub them in the ashes (containing lye) that are all around. And realize that your hands are clean after a quick rinse in water. And if you save that water containing grease and ash, you can clean other things with it, such as tools. ---
**Author:** ![Dorjan](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dorjan/32/12440_2.png) [@Dorjan](https://boards.straightdope.com/u/Dorjan)\ **Post date:** [January 29, 2015, 9:24pm UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/8 "2015-01-29T21:24:56Z")
> [@am77494](#): > > Cite please ? > > I don’t believe what\*\* Dorjän\*\* said is true. Liquid soaps are made using potassium hydroxide as the alkali while solid soaps use sodium hydroxide. Adding water / glycerin will make it only more gooey - but it wont turn into liquid soap. > > From [Wikipedia](http://en.wikipedia.org/wiki/Soap#Liquid_soap): If you were making liquid soap from scratch yes, you would use potassium hydroxide. We’re turning bar soap into liquid and want to keep it that way. Goo is actually a better term - we want really gooey, soap that stays that way. Lots of water and glycerin works fine, the trick is breaking down the bar soap into fine pieces. My cites are the bottle of homemade, liquid, pump-able bar-soap-turned-liquid sitting on my bathroom sink and these: > **[Pinterest](https://www.pinterest.com/search/pins/?q=liquid-vegetable-glycerine)** > > Discover recipes, home ideas, style inspiration and other ideas to try. ---
**Author:** ![Alley\_Dweller](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/alley_dweller/32/430_2.png) [@Alley\_Dweller](https://boards.straightdope.com/u/Alley_Dweller)\ **Post date:** [January 29, 2015, 9:33pm UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/9 "2015-01-29T21:33:50Z")
If you are going to use glycerin. don’t fly. If you get selected for a random hand-swabbing (which can happen even if you are going through Pre-Check), it will [register as an explosive](http://consumertraveler.com/columns/getting-there/tsas-explosive-trace-detection-needs-a-dramatic-overhaul/) and you will get to experience intimate contact with a TSA officer. ---
**Author:** ![jasg](https://avatars.discourse-cdn.com/v4/letter/j/f0a364/32.png) [@jasg](https://boards.straightdope.com/u/jasg)\ **Post date:** [January 30, 2015, 12:17am UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/10 "2015-01-30T00:17:12Z")
Someplace around here I have a ‘secret family recipe’ for liquid soap - from my great-grandfather’s diaries from the 1870s. Offhand, all I remember is that he started from a hard German soap. ---
**Author:** ![Nametag](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/nametag/32/406_2.png) [@Nametag](https://boards.straightdope.com/u/Nametag)\ **Post date:** [January 31, 2015, 8:52am UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/11 "2015-01-31T08:52:08Z")
OK, let’s have a little chemistry lesson. Sodium soaps and potassium soaps are either hard or soft depending on which fats you use to make them. Potassium stearate is hard soap, period. Potassium soaps are used for liquid soaps because they stay in solution better than sodium soaps (actually, that’s making a virtue out of necessity - removing excess water from potassium soaps is difficult). Sodium soaps separate from water readily, and residual glycerin from the saponification reaction is distilled out. It is for this reason that making liquid soap from hard milled soap works better with a plasticizer, and glycerin is an excellent choice. It helps break up that gel-like structure, it doesn’t interfere too much with lathering, and it moisturizes! You still need plenty of water, though, and I suspect this is your main problem. If you put several small soaps in a jar with water, your ratio of water to soap is probably 3:1 or 4:1, and not the 10:1 or more it takes to get a pumpable soap. ---
**Author:** ![picunurse](https://avatars.discourse-cdn.com/v4/letter/p/7bcc69/32.png) [@picunurse](https://boards.straightdope.com/u/picunurse)\ **Post date:** [February 1, 2015, 5:11am UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/12 "2015-02-01T05:11:16Z")
> [@Alley\_Dweller](#): > > If you are going to use glycerin. don’t fly. If you get selected for a random hand-swabbing (which can happen even if you are going through Pre-Check), it will [register as an explosive](http://consumertraveler.com/columns/getting-there/tsas-explosive-trace-detection-needs-a-dramatic-overhaul/) and you will get to experience intimate contact with a TSA officer. Thank you, but I knew that. My husband is a firefighter/ haz-mat instructor. My problem now is buying the glycerin. I went on a scavenger hunt at Fred Meyer. It’s a grocery and other stuff store. They have garden, auto, clothing, shoes, pharmacy, but no glycerin. 6 employees asked if I was finding what I needed. Each one sent me to a different area of the store. Finally, the checker said to check at the pharmacy. They didn’t have it either, but they could order it. I’ll check a crafts store first. So, thank you all for the information. I may forget the whole thing and just buy some white liquid hand soap and tell him I made it from his damn little bars… Wait, that would just make him bring home more… sigh. ---
**Author:** ![Isilder](https://avatars.discourse-cdn.com/v4/letter/i/cc9497/32.png) [@Isilder](https://boards.straightdope.com/u/Isilder)\ **Post date:** [February 1, 2015, 11:30am UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/13 "2015-02-01T11:30:50Z")
The question was about converting cake soap to liquid… to make use of them. But these days they use sodium laureth ethanoate in body or facial liquid soaps , shampoo… Cheap hand cleaner may be sodium laureth sulfate, which can sting the eyes. ---
**Author:** ![Bill\_Door](https://avatars.discourse-cdn.com/v4/letter/b/50afbb/32.png) [@Bill\_Door](https://boards.straightdope.com/u/Bill_Door)\ **Post date:** [February 1, 2015, 11:39am UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/14 "2015-02-01T11:39:50Z")
> [@Alley\_Dweller](#): > > If you are going to use glycerin. don’t fly. If you get selected for a random hand-swabbing (which can happen even if you are going through Pre-Check), it will [register as an explosive](http://consumertraveler.com/columns/getting-there/tsas-explosive-trace-detection-needs-a-dramatic-overhaul/) and you will get to experience intimate contact with a TSA officer. Oh sure, a quick cavity inspection and then afterwards those guys never call, they never write, there’s no closure. Call that intimate? I don’t. ---
**Author:** ![Digital\_is\_the\_new\_Analog](https://avatars.discourse-cdn.com/v4/letter/d/a88e4f/32.png) [@Digital\_is\_the\_new\_Analog](https://boards.straightdope.com/u/Digital_is_the_new_Analog)\ **Post date:** [February 1, 2015, 4:00pm UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/15 "2015-02-01T16:00:30Z")
> [@picunurse](#): > > My problem now is buying the glycerin. I went on a scavenger hunt at Fred Meyer. It’s a grocery and other stuff store. They have garden, auto, clothing, shoes, pharmacy, but no glycerin. 6 employees asked if I was finding what I needed. Each one sent me to a different area of the store. Finally, the checker said to check at the pharmacy. They didn’t have it either, but they could order it. > > I’ll check a crafts store first. I got my glycerin from Michaels, which is a crafts store. It was in the baking supplies section, and is labeled for use in icing. Wilton makes it. ---
**Author:** ![PlainJain](https://avatars.discourse-cdn.com/v4/letter/p/5daacb/32.png) [@PlainJain](https://boards.straightdope.com/u/PlainJain)\ **Post date:** [February 1, 2015, 4:19pm UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/16 "2015-02-01T16:19:45Z")
2 oz bottle of Witons Glycerin: $4.86. Bottle of liquid soap at my Dollar Store: 99 cents. ---
**Author:** ![Joey\_P](https://avatars.discourse-cdn.com/v4/letter/j/919ad9/32.png) [@Joey\_P](https://boards.straightdope.com/u/Joey_P)\ **Post date:** [February 1, 2015, 5:01pm UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/17 "2015-02-01T17:01:38Z")
You should be able to find Glycerin at a pharmacy (like Walgreens). It’ll be with the laxatives. ---
**Author:** ![jnglmassiv](https://avatars.discourse-cdn.com/v4/letter/j/f07891/32.png) [@jnglmassiv](https://boards.straightdope.com/u/jnglmassiv)\ **Post date:** [February 1, 2015, 8:24pm UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/18 "2015-02-01T20:24:13Z")
When I was a kid, I wanted to take up whittling for some reason. I had a small pen knife and someone got me a couple bars of regular white bath soap to practice on. After I stabbed the everliving hell out of my left hand (my left index finger was numb for what seemed like weeks, I still have a scar), I gathered all the little chips and chunks and microwaved them with the intent of pouring into a mold to reclaim the bar. It never solidified and stayed a sort of slimy, viscous consistency. It worked fine in a Softsoap hand pump dispenser. ---
**Author:** ![Nametag](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/nametag/32/406_2.png) [@Nametag](https://boards.straightdope.com/u/Nametag)\ **Post date:** [February 2, 2015, 6:57am UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/19 "2015-02-02T06:57:38Z")
Then it wasn’t regular soap. Regular soap will melt in the microwave and re-harden upon cooling, except it will be crumbly and possibly a little burned (except for Ivory - that stuff has so much air whipped into it that it expands into a crumbly “souffle”). What you had was probably a “bath bar” like Dove (well, not exactly like Dove - that remains a little soft, but not liquid). ---
**Author:** ![Enola\_Straight](https://avatars.discourse-cdn.com/v4/letter/e/dec6dc/32.png) [@Enola\_Straight](https://boards.straightdope.com/u/Enola_Straight)\ **Post date:** [February 2, 2015, 4:10pm UTC](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259/20 "2015-02-02T16:10:23Z")
> [@am77494](#): > > Cite please ? > > I don’t believe what\*\* Dorjän\*\* said is true. Liquid soaps are made using potassium hydroxide as the alkali while solid soaps use sodium hydroxide. Adding water / glycerin will make it only more gooey - but it wont turn into liquid soap. > > From [Wikipedia](http://en.wikipedia.org/wiki/Soap#Liquid_soap): I thought solid soap was made from animal fats whereas liquid soap was derived from the lighter vegetable shortening. [Next page](https://boards.straightdope.com/t/can-i-make-liquid-soap/711259.md?page=2)