CA, Table Salt and SF

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penelopejane

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I have used Citric Acid, Table Salt and low SF together and separately in the same recipe and I just can't work out what they bring to the soap and would be really pleased if some of you could help me out as I am so confused about these additives.

CA is supposed to stop soap scum but it can make a soap soft.
Does anyone find CA effective? What am I looking for if I use it?

Table salt is supposed to make a bar harder. I think this works. But I think TOMH said that it might just be a temporary measure while the soap cures - is that right?

So if I use both CA and salt will I have a hard bar with no soap scum?
Or will they cancel one another out and I end up with a soft soap with soap scum?

Low or zero SF can also reduce soap scum - is that right?
Does it make a soap drying to the skin?
 
Low or zero SF can also reduce soap scum - is that right?

No, soap scum is the reaction of the soap to the minerals in the water that make the water "hard". It has little or nothing to do with superfat.

Does it make a soap drying to the skin?

Yes.

(I have soft water, so I can't answer anything but these. Sorry.)
 
No, soap scum is the reaction of the soap to the minerals in the water that make the water "hard". It has little or nothing to do with superfat.



Yes.

(I have soft water, so I can't answer anything but these. Sorry.)

Thanks for the help, Susie.
I'm not sure if we have soft or hard water.
 
If you were in the US, I would tell you to contact your local water board or city utilities for a water report. They are mandated to test and publish the information yearly. The information of what is in our water is on there. Also, you can Google water hardness for US areas. Let me see if I can find that for Australia.

ETA: I can't locate that information, but I see several water boards reporting their water quality online, so I am sure you would have more luck. If nothing else, you can find what aquifer your water comes from, then find a local water board that draws from the same aquifer.
 
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I do not find low superfat 0-3% in the least drying depending on your total soap profile. Depending on how much CO and Pko I am using, makes the difference on the superfat I use. I do know for a fact higher superfats affect poor plumbing, all I had to do was check my plumbers receipts. I am using a year + old soap that is a minus superfat because I managed to leave out an oil, although not my favorite soap it does not dry my skin and it is one I am not selling.
 
I don't have hard water so I can't answer for it. I can say that a low superfat soap does have other advantages, especially if you're making a milk soap and don't want to have to really calculate the amount of fat in that milk or cream to be used. As for the said soap being more drying, that is totally dependent on your recipe.

About the salt thing, I've only used salt a handful of times and that was in my solseife attempts. 100% CO or high CO soaps are not my thing. Every soap I've used high CO in has taken more than 24 hours to unmold and they were STILL soft, even with salt. Even my castile bars unmolded with more ease than that.
 
If you were in the US, I would tell you to contact your local water board or city utilities for a water report. They are mandated to test and publish the information yearly. The information of what is in our water is on there. Also, you can Google water hardness for US areas. Let me see if I can find that for Australia.

ETA: I can't locate that information, but I see several water boards reporting their water quality online, so I am sure you would have more luck. If nothing else, you can find what aquifer your water comes from, then find a local water board that draws from the same aquifer.

Thanks I will try this on monday. I did this and apparently we do not have hard water.

About the salt thing, I've only used salt a handful of times and that was in my solseife attempts. 100% CO or high CO soaps are not my thing. Every soap I've used high CO in has taken more than 24 hours to unmold and they were STILL soft, even with salt. Even my castile bars unmolded with more ease than that.

Hi Arimara,
I was only talking about 1/2-1 tsp of table salt ppo.
A tiny amount really but my DH thinks it makes a difference to the hardness.
I'm not sure.
 
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I do not find low superfat 0-3% in the least drying depending on your total soap profile. Depending on how much CO and Pko I am using, makes the difference on the superfat I use. I do know for a fact higher superfats affect poor plumbing, all I had to do was check my plumbers receipts. I am using a year + old soap that is a minus superfat because I managed to leave out an oil, although not my favorite soap it does not dry my skin and it is one I am not selling.

So you changed the SF and used CA (but now EDTA) and your soap scum has been reduced. I imagine the higher SF would have left soap scum in the pipes or is it something else?
 
The higher superfat is fat, not soap scum -- fat can't turn into soap scum because it's not soap to begin with. Perhaps the excess fat and the scum interact and stick to the pipes as the soapy water washes down the drain? Soap scum is a type of soap after all (not soap as we know it, true, but still a soap), and soaps do like to bond with fats.
 
The higher superfat is fat, not soap scum -- fat can't turn into soap scum because it's not soap to begin with. Perhaps the excess fat and the scum interact and stick to the pipes as the soapy water washes down the drain? Soap scum is a type of soap after all (not soap as we know it, true, but still a soap), and soaps do like to bond with fats.

Fat & grease are a notorious plumbing problem. One would think 'It's greasy, wouldn't it just slide through pipes?' But no, that's not what happens. It gets cold once inside the pipes, solidifies and gets stuck on the inside of the pipes and along with other stuff that gets flushed down the drain, the lumen is occluded by various gunk causing hideous looking clogs. (Have you ever used a Zip-It? I do periodically and the result is that I pull out clogs that look like drowned rats.)

In the kitchen, grease, fat, food particles (especially rice or anything that expands when wet), plus soap scum. In the shower and sinks, hair, dead skin particles, hair (yes, I shed a lot of hair), beard shavings (a pet peeve of mine because I have to clean the sink after my husband shaves before I can wash my face), small pieces of soap that fall into the drain (those tiny little bits when the soap is almost used up), dirt, sand, excess fat, etc.


NB, because my hair is so long and because I shed so much of it, I do my best NOT to let it go down the drain. I try to catch all loose strands and put them in the trash can after my shower and hair washing. Same is true for when I clean the floors, as my hair sheds onto the floors, too. Even vacuuming my hair causes problems with my vacuum cleaner (gets stuck on the beater bar brush and that leads to breaking the rubber belt and potentially burning out the motor.) So I use a pet hair broom on the carpet to get my hairs before I ever use the vacuum.
 
Fats clog the drains not the soap scum. According to my plummer any soap will contribute to clogs over time. Since my house is below street level and my lines do not any fall to them, again according to our plumber, all the junk will lay in the pipes until it can get flushed up to the main sewer. The solidified fats get caught in roots and exacerbate plumbing problems.
 
I have used Citric Acid, Table Salt and low SF together and separately in the same recipe and I just can't work out what they bring to the soap and would be really pleased if some of you could help me out as I am so confused about these additives.

CA is supposed to stop soap scum but it can make a soap soft.
Does anyone find CA effective? What am I looking for if I use it?

Table salt is supposed to make a bar harder. I think this works. But I think TOMH said that it might just be a temporary measure while the soap cures - is that right?

So if I use both CA and salt will I have a hard bar with no soap scum?
Or will they cancel one another out and I end up with a soft soap with soap scum?

Low or zero SF can also reduce soap scum - is that right?
Does it make a soap drying to the skin?

CA can help with soap scum. The reason it is useful due to the reaction with lye to get converted into Sodium/Potassium Citrate. This post may help provide greater detail:

http://www.soapmakingforum.com/showthread.php?t=56643

I find it easier to just use Sodium Citrate to achieve the same effect without having to recalculate anything. I've used it successfully at 3% of my total oil weight (i.e. 500g of oil = 15g Sodium Citrate used) and I do notice the difference. I dissolve the Sodium Citrate in water (or whatever liquid being used) before adding the NaOH/KOH to create the lye solution. It does not seem to significantly soften my soap.

How can I tell the Sodium Citrate helps? I have pretty hard water and when I rinse with normal soaps I can feel the residue on my body and hands. If you don't have hard water, you may not notice any difference.

I prefer to use Sodium Lactate over salt to harden a bar and this is mostly to help with unmolding the soap earlier. Salt can also achieve the same effect but I understand too much may potentially inhibit lather (unless otherwise compensated for). Curing time is more important for long term results with respect to hardness and longevity.

Hope that helps!
 
So you changed the SF and used CA (but now EDTA) and your soap scum has been reduced. I imagine the higher SF would have left soap scum in the pipes or is it something else?
I lowered my superfat several years ago. For one I use low coconut oil in most soaps and it was just to hard to rinse off with the higher superfats. Always felt like I was washing with oil and not soap
 
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