Will sodium Citrate prevent soap going rancid?

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Jen74

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Hey all.

I know I have made some posts a month ago about my soap that keeps going rancid on me two to three weeks into curing. The only thing I can think of is that I am not adding a preservative of some sort to prevent the oils from going. I know someone on here mentioned adding Sodium CItrate to the lye in order to prevent rancidity. Just wondering if this will prevent soaps from going rancid? Also, how much do you usually add? My recipe is below. I use this one because it is like the only one I can tolerate. I used Soapcalc for the recipe.

Palm kernel oil- 6.40 ounces
Palm oil- 25.60 ounces
water- 9.18 ounces
Lye- 4.52 ounces
 

Jen74

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If you soaps are going rancid, you might need new oil(s). I can't recall if sodium citrate helps with rancidity but I doubt it does.
My oils are okay though. The soap goes rancid two to three weeks into curing. I am not sure, but my only thought is maybe it has to do with humidity in the house? I do not have this issue in the winter when the humidity is very low. I do keep my AC on though so not sure why this is happening. I need to add something to the soap to prevent them from going rancid. Any ideas?
 
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What is your superfat percentage?
If it is 5% I’d try reducing it to 1% and see how you go.

handmade soap with fresh oils won’t need an additive to prevent it going rancid. You need to find the cause.
Are you sitting the soap on metal trays to cure?
Are you using metal implements other than stainless steel?
Do you always use gloves to touch your soap?
Is there a lot of good ventilation in the area you cure your soaps?
Is dust or pet hair getting on your curing soaps?
does sunlight get in your curing soaps?
how hot does the room where your soaps cure get?
Is it very humid? Do the soaps sweat?

sodium citrate is a chelating agent that helps reduce soap scum. If you use it in soap you have to neutralise it (add extra NaOH) Or you will get a higher superfat and soft soap.
 
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DeeAnna

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Yes, sodium citrate will reduce the chance of rancidity in soap. Citrate is a "chelator" which is a type of chemical that traps and "de-activates" metallic contaminants. Metals are a major reason why soap and fat can go rancid.

Citrate (and other chelators) also reduces soap scum, although no chelator will be a surefire 100% cure-all for soap scum. But it helps.

You would also be wise to also add rosemary oleoresin (ROE) as lsg suggests to all of your newly purchased fats if they don't already include an antioxidant. ROE is a very effective antioxidant for fats; it will help prevent rancidity that is caused by reasons other than metallic contamination.

More info: Table of contents | Soapy Stuff
 
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Good advice above, but it does seem unusual that multiple batches have gone off so quickly. Is the soap or batter coming into contact with any metal that isn’t stainless? Some chrome-plated racks that look like stainless aren’t and will cause problems.
 

DeeAnna

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Yeah, I've been wondering too why your soap is going rancid so quickly. It seems to me that there's something odd happening that's not obvious from the information you've shared here.

Antioxidants and chelators are useful and effective, but they're more like a mousetrap. If you have only a few mice to control, they work very well. If you have a horde of mice, even the best mouse traps will get overwhelmed.
 

ResolvableOwl

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@Jen74 Have you followed all the advice in your former thread
and you're still targeted by DOS? You left the glycerol out, and bought new oils? Back then, multiple people already recommended you to use citrate. If you take such advice lightly, you will be annoyed by more soap batches going bad, and helpful people will be annoyed to recommend you the same things over and over again.
 

Jen74

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Yeah, I've been wondering too why your soap is going rancid so quickly. It seems to me that there's something odd happening that's not obvious from the information you've shared here.

Antioxidants and chelators are useful and effective, but they're more like a mousetrap. If you have only a few mice to control, they work very well. If you have a horde of mice, even the best mouse traps will get overwhelmed.


I bought all new oils and molds for this last batch. Only thing I can think of is that maybe it has something to do with the humidity in the house. I cannot think of anything else. I can try adding some ROE or sodium citrate and see if that helps. I'm at a loss...
 
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This has to be so frustrating for you! Are you sure that:

1. You are using distilled water?
2. The batter and bars do not have any contact with any metal (even if you think it is stainless steel)?
3. The soaps are out of direct (or even indirect but bright) sunlight?
 

Jen74

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This has to be so frustrating for you! Are you sure that:

1. You are using distilled water?
2. The batter and bars do not have any contact with any metal (even if you think it is stainless steel)?
3. The soaps are out of direct (or even indirect but bright) sunlight?


Yes use distilles water. No metal contact at all. They are not in direct sunlight, but not exactly in the dark either. The odd thing is all winter long I can make them, no problem. I think it might have something to do with the humidity.
 
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What is your superfat percentage?
If it is 5% I’d try reducing it to 1% and see how you go.

handmade soap with fresh oils won’t need an additive to prevent it going rancid. You need to find the cause.
Are you sitting the soap on metal trays to cure?
Are you using metal implements other than stainless steel?
Do you always use gloves to touch your soap?
Is there a lot of good ventilation in the area you cure your soaps?
Is dust or pet hair getting on your curing soaps?
does sunlight get in your curing soaps?
how hot does the room where your soaps cure get?
Is it very humid? Do the soaps sweat?

sodium citrate is a chelating agent that helps reduce soap scum. If you use it in soap you have to neutralise it (add extra NaOH) Or you will get a higher superfat and soft soap.
What does sunlight do to curing soap??
 

DeeAnna

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UV light from any kind of light source will cause the soap to go rancid. Soapsmith' s DOS Experiment

Adding ROE to soap is fine, but it's even better if you add it to your fats as you receive them. Fats oxidize during storage, so why not add ROE early on so you get better protection?
 
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Kinda glad this topic came up. I actually came on here today exactly for finding out how much citric acid to use in cp soap, so off to @DeeAnna website I go lol.

I also need to rethink my curing spot I guess, cause while the dont receive direct sunlight, the room is very sunny just from the windows.

Hopefully between the two solutions, i will cure my dos problem. Its not a huge problem. It only seems to affect the prettiest bar in the batch 🤣
 
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Yes use distilles water. No metal contact at all. They are not in direct sunlight, but not exactly in the dark either. The odd thing is all winter long I can make them, no problem. I think it might have something to do with the humidity.
Maybe you have more sunlight in the room during this time of year. That is certainly true for some of the rooms in my house.
 

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