Soap "Dust"

[SoapMan]

Hi everyone, first post!! Sorry for the long post in advance just trying to explain myself and would love a solution to my issue. Thanks in advance for taking the time to read!!

I have been making cold process soaps for 3-4 years. Recently past year or so I have been having issues with soap dust. Basically a white thin residue on my finished soaps. In the past this wasn't an issue for me. I moved around the time when I started having soap dust issues, but not positive they are linked. I write my own recipes, and they will vary slightly (which oils I use) but generally are similar ratios of liquid oil, solid oils and lye. I have soap dust on all my recopies these days.

I can post an example of a recipe if needed but guessing this issue has something to do with temperature or my process. So I will describe my process first and see if any one can point out a change I should try. I have tried changing up a few factors but so far nothing has helped. My basic process is below.

I combine my lye solution (NaOH + H20) with my oils around 95F, +/- 4 or 5 degrees. I use wood loaf molds with lids. After I combine and pour into molds, I place the lid in the mold. I place the mold on a wire shelf wrapped in towels on top and bottom. After 16-18 hours I remove the mold from "insulation" (the towels) and remove the lid. Usually 48-52 hours after pouring I will remove the soap from the mold and cut into bars, usually leaving the "rough" look on top from pouring. Then I let the soap cure for 4 weeks.

Couple things have changed over the past year that are suspect to me causing the issue. Obviously the room where I store the soap has changed. Worried that the new soap room might be too drafty. What is an ok range of room temperatures during saponification? I live in Southern California so the room will get chilly but never freezing cold.

Also I had a buddy make me some new soap mold boxes, that I started to use around this time. I have tried going back to my old boxes, but did not notice a difference, but still a little worried this could not help the issue. Without consulting me, my buddy decided to have the bottom of the boxes pine ("because it is a more dense wood" at least his explanation) and the rest of the box is oak (need to double check it's oak but pretty sure). I have always been worried that having the 2 types of wood, would make the soap cool at different rates and could cause something like soap dust. But like I said I tried my old boxes a couple times with the new boxes (using the same batch of soap) and both got soap dust.

The third thing that has changed is my recipes. I am always playing around with my recipes and trying new oils and butters. At the same time the meat and potatoes of my recipes does not change too much.

I searched around on the forum a bit, but could not find many solutions. Any help would be greatly appreciated, this issue has me pulling out my hair. Thanks so much for taking the time!!!

Brent

 

[Relle]

I presume when you say soap dust you are talking about Soda Ash ? Type that into the search engine and a lot of info comes up (pages and pages) from people that have had issues with it before and some solutions to their problem.

 

[SoapMan]

Relle9 -

Thanks so much for the speedy response!! Yes you are correct, guess the correct term is "soap ash." Had seen it both ways and wasn't sure which was "correct." Googling now and some ideas I have read are below and would be curious what others think. I'm just really perplexed by this issue, sense I use to not have it and now can't get rig of it ha.

Suggestions from a google search:

Lye "heavy" - this seem like the extreme situation. Sounds like it looks different then my issue and pretty sure isn't the cause sense my soap is fine to use. My soap ash is just a very thin layer.

Cover with plastic wrap - For some reason I always thought it was bad to use plastic wrap with cold process soaps? The explanation I was told was that CP soap needs to "breathe." But this usually relates to the packaging phase. I generally use a type of wax paper to line my soap boxes. To try this I would still use the wax paper in the box and then just use plastic wrap on top or wrap the outside of my wood loaf with plastic wrap? Has anyone had luck doing this?

Don't un-mold so soon - Well I came up with un-molding after 48-52 hours because generally if I go another day it becomes very hard to get out of my loaf mold. Will give this a shot next batch. How long are others here keeping your soap in a wood loaf mold after pouring?

Add Soy Wax or Bees Wax - Not into using bees wax (no animal byproducts for me) but will try the soy wax. Writing a recipe now to try with this. Actually might help with 2 problems. My soap is usually on the softer side also, this might make it slightly harder.

Use less Lavender - Well that's a bummer that is one of my favorite fragrances ha. Doesn't seem what is affecting me, sense I do batches without lavender and still have the issue.

Use Purified Water - Already use distilled water.

Room Humidity - This idea has me curious. I live in Southern California and it can be dry here, which seems preferred. But maybe for some reason my soap room in my new house is more humid? Have no idea why this would be, but going to get a dehumidifier and try it out.


Honestly just happy to have other things to try besides pour temp. Before when I was looking into this for some reason thats all I could find, probably helps to have the right terminology

So what I am thinking of trying next and someone please correct me if this is silly!! I will still line my mold with wax paper, and place lid. But next time I am thinking about wrapping my mold with plastic wrap, to keep out air. Do my normal insulation for 18 hours, then remove towels and after 48 hours remove plastic wrap. Maybe wait another 24 hours and cut. This seem like a waste or silly? Just seems weird to line my mold in plastic wrap inside, also if I do this I can not remove the plastic wrap until I cut. So thinking wax paper inside to line and then wrap on outside with plastic wrap.

Also I am going to look into the humidity in my room. Anyone know an ideal humidity? Everywhere I looked it would say "low," but not give a level.

Again thanks so much taking the time to read this, sorry so long. Just this issue has been driving me crazy for a long time and I want to solve it if possible!! Also any other solutions or things to try please feel free to toss them out there, thanks!!

 

[Hazel]

Several people have mentioned spritzing the top of the soap with rubbing alcohol before covering it to reduce or eliminate ash. You can spritz again after removing the plastic wrap. FYI - a comment was made rubbing alcohol will dull glitter if you ever decide to put it on soap.

Covering the top of the soap with plastic wrap is to keep air off the top while it is going through saponification. I've read ash is sodium carbonate which is formed from sodium hydroxide interacting with carbon dioxide. Once the batch has saponified, there shouldn't be any "free" sodium from the lye available to combine with the carbon dioxide to produce ash. You don't have to wrap the entire mold. You just have to keep the exposed top covered until saponification is complete - normally a day or two if you gel your soap. It will take longer if you don't gel - several days or longer. I don't know how much humidity affects the formation of ash. I do know high humidity affects the length of curing because it slows water evaporation. I don't think humidity in Southern California would ever get high enough to really be an issue.

I used wax paper once to line a wooden mold. I had a terrible time getting the soap out and the wax stuck to the soap. I had to peel it off and it kept shredding. Freezer paper works much better. You line the mold with the shiny side to be against the soap. It's much easier to remove the soap and pull the paper from the soap.

Room temperature - it depends whether you want your soap to gel or not. Gelling should occur as long as a mold is kept well insulated. Normally, the combination of wood (which holds heat) and the towels should be enough to prevent heat loss even in a cool room. However, you're combining the oils and lye solution at a low temp which might not be enough to ensure full gel even with insulation. You can always warm your mold in the oven before pouring the soap in it to help hold heat and ensure a full gel. That's what I do in the colder months. If I don't want a batch to gel, I'll put the mold in the freezer before pouring the soap and then stick it in the frig (this is during hot months).

I don't know if any of this helps. Sometimes you get ash no matter what you do.

 

[sperry]

Sorry if this is a waste of your time... It's probably totally irrelevant. I was experimenting with felting soaps. I wrapped a bar of store bought soap (cold process, I assume) in wool, felted it, and threw it somewhere and forgot about it. A few weeks later I took the felt off and almost died on the dust. It was beyond horrible. I figured something in the wool "sucked" the moisture out of the soap, and created the powder. SoCal is very dry. Maybe that and a different kind of covering when you cover your loaves? Clutching at straws, I know... but what the heck.

 

[Lindy]

Hello there. I use ethanol to spritz the tops of my soaps with and I rarely get ash. I find rubbing alcohol just isn't quite enough (I also live on the coast). I buy my ethanol from Voyageur Soap & Candle but I expect you should be able to find it from US suppliers as well.

 

[SoapMan]

Hazel -

Thank you so much for your detailed response, appreciate it!!

Thanks for the heads up on spritzing the top with rubbing alcohol. Will keep that in mind but would like to find a better solution, if possible.

Makes sense about heat and just covering the top. Thanks for the explanation. I also found a really good description of reasons for the sodium carbonate forming on a chemistry forum. Will give covering the top of the soap with plastic wrap after pouring next batch. Now that I'm thinking about it my old boxes, the lids "sat" more on the soap, i.e. went deeper into the box and sat directly on the soap. My new boxes the lids are tighter, so the lid doesn't just fall into the soap like the old. This has been probably leaving a gap of air between the lid and the soap. Just a random thought, will watch out for this next time also.

Funny you brought up wax paper. Actually when I started out a few years back I would use wax paper. It was a huge pain like you said, always an issue getting it all off. I ended up buying a large role of paper from a soap ingredient distributor and have been using that the past couple of years. Was using "type of wax paper" in a generic sense, because silly me didn't know what the other was called. So again thanks so much because now I know what it is called next time I need to restock.

Would you recommend me trying a higher pour temperature? How high 110F? I don't use goats milk or anything like that, that would force me to have a low pour. Just for some reason always had it in my head that it was better to pour at lower temps. But really have no reasoning on it, will do some research around the site.

Agree wouldn't think humidity would be an issue for me in southern California. Will put humidity on the back burner of things to look into. Probably an unlikely suspect.

I'm obviously pretty new to this (couple years) and have never met anyone in person that also made soap. So I have been just trying things out by myself. So excited to have found this forum!!

 

[SoapMan]

Sorry if this is a waste of your time... It's probably totally irrelevant. I was experimenting with felting soaps. I wrapped a bar of store bought soap (cold process, I assume) in wool, felted it, and threw it somewhere and forgot about it. A few weeks later I took the felt off and almost died on the dust. It was beyond horrible. I figured something in the wool "sucked" the moisture out of the soap, and created the powder. SoCal is very dry. Maybe that and a different kind of covering when you cover your loaves? Clutching at straws, I know... but what the heck.

Thanks! Actually I read the opposite somewhere. That low humidity was better, i.e. less soap ash. Maybe I misunderstood and they were just referring to soap making in general or was a bad source. Either way your example makes sense and will defiantly look into it. Thanks again!

 

[SoapMan]

Hello there. I use ethanol to spritz the tops of my soaps with and I rarely get ash. I find rubbing alcohol just isn't quite enough (I also live on the coast). I buy my ethanol from Voyageur Soap & Candle but I expect you should be able to find it from US suppliers as well.

Because of my work I have isopropyl alcohol (also used to clean old tape machines) . Will look into if this is the same or can be used. If not will order some.

Have so many things to try, I'm so excited to make soap, but err just noticed I am low on coconut oil. Time to order some. :cry:

Thanks again to everyone that has chimed in!!

 

[Relle]

Brent, glad you found your answers , I couldn't write a long reply as I keep getting logged out of the forum automatically :evil: . The search engine I meant for you to look up is the forum one - at the top of the page right hand side, not google.You might find answers in there if you have some questions in the future, its a great resource.

 

[SoapMan]

Brent, glad you found your answers , I couldn't write a long reply as I keep getting logged out of the forum automatically :evil: . The search engine I meant for you to look up is the forum one - at the top of the page right hand side, not google.You might find answers in there if you have some questions in the future, its a great resource.

No worries at all!! You helped me with the proper term to search, appreciate it!! I see what you meant now and will dig through some of the threads. Honestly I am thrilled I have many things to try now. I was getting a little beat down by this ash issue. Love the forum by the way!! Thanks!

 

[Hazel]

Would you recommend me trying a higher pour temperature? How high 110F? I don't use goats milk or anything like that, that would force me to have a low pour. Just for some reason always had it in my head that it was better to pour at lower temps. But really have no reasoning on it, will do some research around the site.

It depends on whether you prefer gelled soap or non gelled soap. I mix oils and lye solution at a higher temp (somewhere around 110F or slightly higher about 120F) when I'm making a batch I want to gel. I mix at cooler temps (100F or slightly lower) for soaps which I don't want to gel. Unfortunately, sometimes they start to heat up and I get partial gel. I can't say exactly what temps I mix everything at - it's more of a range of temperature. Many soapers pour at lower temps. It comes down to personal preference. Mixing the oils and lye solution at cooler temps slows trace a bit and gives you more time work with the soap if you want to add several colors or have a temperamental FO. However, you can still gel the soap if you mix at a lower temp by using the CPOP method.

It might be better to mix at a higher temp if you have a large percentage of saturated fat in a recipe. If the temp gets too cool, the saturated fats may start to solidify which can fool you into thinking you've got trace. Ask me how I know. :roll:

You might find these discussions of gelling vs non gelling interesting to read. But then again, maybe you won't find them interesting.

http://soapmakingforum.com/viewtopic.php?t=25208
http://soapmakingforum.com/viewtopic.php?t=31429
http://soapmakingforum.com/viewtopic.php?t=24721
http://soapmakingforum.com/viewtopic.php?f=1&t=4472

There was another discussion about gelling in which someone discussed CPOP but I can't find it now. However, you can also search for topics on CPOP.

 

[SoapMan]

Hazel -

Thanks so much. I use to go higher, i.e. 100-110 F range. But for some reason got in my head I should go cooler, think it was when I first started to get soap dust. My batches few years ago would gel (higher pour), but mine now do not. Knew there was a difference but honestly never knew the term or reasoning behind it.

Ha it's like you read my mind, was just about to start looking for Gel vs Non Gel discussions. Think next time I will gel the same recipe I just made, that way I can compare.

When making the soaps the things that are most important to me personally is the moisturizing qualities for skin, like to keep it as natural as possible (minus NaOH obviously), and no animal byproducts. Just personal prefs.

Will do some research and bet I will find opinions on how gelling effects qualities for skin, if it does. My thought process (not that it is correct) was cooler was always better. For reasons like heat breaking up vitamins in your oils left in the soap. But from my understanding most vitamins break up around 120F or higher, so 110 should be safe. But who knows, I am still learning so much about soap, so I could be completely off.

Thanks so much for the info!! Going to start digging through those threads!

 

[Hazel]

My thought process (not that it is correct) was cooler was always better. For reasons like heat breaking up vitamins in your oils left in the soap. But from my understanding most vitamins break up around 120F or higher, so 110 should be safe. But who knows, I am still learning so much about soap, so I could be completely off.

It's not the heat you have to worry about destroying vitamins in the oils. It's the Lye Monster.


You could try hot process if you want to use certain oils for vitamins or specific properties. You can add them after the cook to superfat the soap.

HP - Crockpot and Stove

Ms. Brenda's tutorial HP in a crock pot
Gracefruit's HP tutorial

HP on the stove. I was amused by her writing style and she has lots of pictures showing the steps the soap goes through while it's cooking. However, I'd recommend using a double boiler if you're only doing a small batch.

You're welcome!

 

[SoapMan]

It's not the heat you have to worry about destroying vitamins in the oils. It's the Lye Monster.


You could try hot process if you want to use certain oils for vitamins or specific properties. You can add them after the cook to superfat the soap.

HP - Crockpot and Stove

Ms. Brenda's tutorial HP in a crock pot
Gracefruit's HP tutorial

HP on the stove. I was amused by her writing style and she has lots of pictures showing the steps the soap goes through while it's cooking. However, I'd recommend using a double boiler if you're only doing a small batch.

You're welcome!

Hmm interesting, good to know! For some reason I always thought this was the reason you "super fat" CP soap? As in the lye monster gets the oils that go through saponification, but then leaves the "extra oils." Also thought it was the point of CP soap, in that keeping temperature down, would cause the oils to break up less in the oils that are left after "superfatting?"

But like most things on soap I am still learning so probably way off. Thanks again for the info, appreciate it!!

 

[Lindy]

With CP you have all the oils in there prior to saponification so the lye takes want it takes and leaves what it leaves. Only HP is going to let you determine what you are using for your superfat because you are adding them at the end of the saponification process. With CP saponification takes 24 - 48 hours depending on whether or not you are gelling your soap. I've had ungelled soap zap for up to a week :shock: HP is done when the zap is gone.

Also (I didn't go to the links) add Sodium Lactate to get a nice smooth pour. This is what my HP looks like:

It still has a rough top but the bar itself is smooth. I know a lady in the EU who makes the most amazing HP and you wouldn't be able to tell the difference in appearance from her HP to most peoples CP it's just that nice. This is my Pine Tar Shampoo in case you were interested :wink:

The other thing I find about HP is there is no ash on top either....

 

[Hazel]

For some reason I always thought this was the reason you "super fat" CP soap? As in the lye monster gets the oils that go through saponification, but then leaves the "extra oils." Also thought it was the point of CP soap, in that keeping temperature down, would cause the oils to break up less in the oils that are left after "superfatting?"

Superfatting soap is to ensure that a batch isn't lye heavy. When you add oils, the lye is going to take whatever it wants and saponify those oils. If you use a 5% SF, you have 5% unsaponified oils remaining in a loaf but you won't know which oils are left. Also, it takes a day or two for saponification to be complete so adding an oil at trace doesn't ensure that it remains unsaponified. The gel phase gets very hot. I don't know how hot but since the loaf becomes translucent, I'd guess it's at least 160F and probably hotter. The unsaponified oils are still exposed to heat.

If you want your oils to remain on the cool side, then you can soap at your normal 95F or room temperature and put a batch in the frig to prevent gel. It will take longer to saponify but it will protect all the oils from heat. Most of the batches I've put in the frig usually take 4 days to saponify but I did have one batch that took 6 days. I'm mentioning this so you don't worry if it takes longer than 4 days if you decide to try this method.

In hot process, you've cooked the soap to force gel and all the lye will be gone by the end. Once the lye is gone, you can add the oils you want for your superfatting oils and then put the soap into a mold. HP soap can be very stiff at the end so it might be hard to stir the oils into it. You can add sodium lactate (2%-3% ppo) or add sugar in the batch to help keep the soap more fluid. When I use sugar, I add it at 4% ppo but you can a higher percentage. I was told by an experienced soaper that she uses 5% ppo. This is something you might want to experiment with because you might find less sugar works fine.

eta: I just saw Lindy had already replied to your post.