Preserving Liquid soap

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penelopejane

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I have just made my first liquid soap thanks to Irish Lass and Susie. Phew! It worked out exactly as you said. Thank you both very much.

Now I’d like to preserve it as naturally as I can - without PS80 if possible. It looks like ROE and Vitamin E not do as preservatives.

One natural soap company uses potassium citrate. Is that a preservative?

One site I read (Preservatives in Liquid Soap) says to use Phenonip or Germall. Does anyone have any experience with either of these?
Phenonip contains: Phenoxyethanol, Methylparaben, Ethylparaben, Butylparaben, Propylparaben
Germall contains: Propylene Glycol (and) Diazolidinyl Urea (and) Iodopropynyl Butylcarbamate.

Naticide pH 4-9 seems to be another possible solution? Has anyone experience with it as a preservative for liquid soap?

Optiphen natural has phenoxyethanol and caprylyl glycol (which to me sounds like ps80)

Dr Bronners only used Vitamin E and citric acid if that is considered a preservative.
 
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I'm not an expert on it by any means, but this is what I recall from my own research of the subject.

There is not a consensus as to whether preservatives are needed for liquid soap - higher risk factors include diluting with a large amount of liquid, and diluting with things other than water.

Storing the soap as paste and diluting it as needed for use is a great way to minimise the risk.

The high pH of the liquid soap (whether in paste form or not) makes it relatively inhospitable for organisms to grow in. Conversely, many/most preservatives are only effective in a pH range which is not compatible with soap, and trying to make it get there is likely to cause the soap to split.
 
I've been making liquid soap since 2004 and never used a preservative. It makes no sense to me, but that's just me (and a large group of LS-ers from the Yahoo Liquid Soapmakers Group.) To quote Catherine Failor, author of the "Bible" of liquid soapmaking, "Fully saponified soap requires no preservative."

Logic tells me, if it did require preservative, there would be one suited for it and there isn't. Preservatives are specific to pH of the product and finding one that works for an alkaline product like soap is unlikely. My liquid soaps tend to be pH 9.5 to 11. Even
my highly diluted foamer soap has a pH around 10 (scroll down). The paste is diluted at a rate of 40% soap to 60% water, then further diluted for the foamer at a rate of 1 part LS to 3 parts water.

That being said, using a preservative is a matter of personal choice. Here's an article that explains when it might be prudent to add it and recommendations for a preservative:


pH and Preservatives in Liquid Soap
 
Thanks LSG and Zany. I've read that info but I think I'd prefer a preservative. Suprapein (plantserv s) and Naticide sound great but are just stupidly $$$ .
I think I'll go with germall which is tested for pH8 but works up to pH 10. My LS isn't for sale.
 
I have just made my first liquid soap thanks to Irish Lass and Susie.
If you did @IrishLass 's recipe, I remember her mentioning somewhere in that thread that she doesn't use preservative but would do if she were to sell. My advice, for your own peace of mind, would be to make 2 4-oz. samples, one with preservative; one without and set aside for a year to see if it makes a difference. I'm guessing the one with preservative will have an odor, i.e., some LS morphs over time with preservative added, or so I've read but didn't save the info. ☹
 
Thank you. Yes I was intending to do that. I am going to give it to friends atm so I don't want to give them unpreserved soap regardless of whether it is indicated or not. Being friends I can also tell them if it smells off throw it away and I'll give them more.

There are also natural EOs that have been proven (??) as preservatives (that are not $$$$$) that I can try, too, when they are available (covid seems to have effected all FO and EO supplies!). They don't get rendered useless in high pH environments.
 
There are also natural EOs that have been proven (??) as preservatives (that are not $$$$$)
I have read that but I have not tested that theory.

I've also read that ROSIN has preservative qualities and I believe that to be true. I once found a 4 oz. bottle of my Flaxseed, Coconut & Rosin Shampoo that was 4 years old. When I opened it, it smelled as fresh as when it was first made and performed like new!

I also add (antioxidants) ROE & Vitamin E to the oils in every batch of soap I make, hard bars and LS, to avoid rancidity.
 
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I am just researching recipes for lotions and liquid soaps in order to develop products to sell, so I don't have a lot of experience yet. In my research I have found that natural preservatives don't do as well in preventing gram positive, gram negative or fungus but they do provide some protection. IMHO, if you are making liquid soap for your own personal use, you can use a natural preservative. I have some diluted liquid soap that I made several years ago without any preservative and still looks fine - no signs of mold. I would hate to see what a microbiological test would show though! If you are selling, just to be on the safe side, IMHO you should use a broad spectrum preservative that does well with gram positive, gram negative and fungus. You may want to look at ECOCERT approved preservatives. ECOCERT is a European organic certification organization. There are many preservatives approved - Leucidal and NeoDefend are two.
 
IMHO, if you are making liquid soap for your own personal use, you can use a natural preservative.
With all due respect @Becky1024, you make some good points. Have you tried using Leucidal and NeoDefend in lye-based soap? Before making my own LS, years ago I tried a few "All Natural" OTC products with "natural preservatives". Without fail, they all smelled "funky" after 6 months or so. JMHO and experience, I have tried to find something "natural" that works without success.

I would also like to point out that both Dr. Bronners and Vermont Country Store and other similar lye-based liquid soap manufacturers list no preservative in their ingredients. On the other hand, Syndet liquid soaps tend to have preservative -- I imagine it is because the pH of those products are pH7 or below which makes for a friendly compatibility in liquid soap. Not sure. :smallshrug:
 
With all due respect @Becky1024, you make some good points. Have you tried using Leucidal and NeoDefend in lye-based soap? Before making my own LS, years ago I tried a few "All Natural" OTC products with "natural preservatives". Without fail, they all smelled "funky" after 6 months or so. JMHO and experience, I have tried to find something "natural" that works without success.

I would also like to point out that both Dr. Bronners and Vermont Country Store and other similar lye-based liquid soap manufacturers list no preservative in their ingredients. On the other hand, Syndet liquid soaps tend to have preservative -- I imagine it is because the pH of those products are pH7 or below which makes for a friendly compatibility in liquid soap. Not sure. :smallshrug:
I have not tried Leucidal or NeoDefend yet.

It's interesting that the lye soap manufacturers list no preservatives. There is a debate going round whether the pH is high enough to keep the bad stuff away. I don't know the answer.
 
I don't know the answer.
There is plenty of anecdotal evidence plus my 17 years of experience of making and selling "Preservative Free" LS to 2 wholesale customers for me to say, I do know the answer... for me. I'm not "sciencey" at all so I can't speak for those who understand the science of soapmaking. So the quandary remains. Sad, to my mind at least. It shouldn't be a problem. :(
 
I have read that but I have not tested that theory.

I've also read that ROSIN has preservative qualities and I believe that to be true. I once found a 4 oz. bottle of my Flaxseed, Coconut & Rosin Shampoo that was 4 years old. When I opened it, it smelled as fresh as when it was first made and performed like new!

I also add (antioxidants) ROE & Vitamin E to the oils in every batch of soap I make, hard bars and LS, to avoid rancidity.
I use ROE but not Vit E. Was thinking of adding that to the LS thanks.
Look up the Suprapein info - all about natural plant preservatives. Costs an arm and a leg. :(
 
I don't use preservatives. Never have, never will. I make enough paste to last about six months. I dilute enough for only about 3 months. I have kept diluted soap right at two years without seeing anything growing under the microscope. I still am only going to dilute enough for three months. I also don't use ROE because I don't use any short shelf life oils for either bar or liquid soap.

ETA: I give diluted liquid soap to all of my immediate family and closest friends. I even ship it to other states if they are willing to accept the paste and dilute it as shipping is expensive.
 
I am pretty sure that here in the UK and in Europe the cosmetic safety assessors say that a preservative is not required, and they are the qualified ones putting their heads on the line to pass our products for big, small and home producers as is required by law over here. Hope that helps.
 
Susie and gloopygloop
It’s good to hear your experiences. I might leave the preservative out for a while and see how it goes. I’ll warn my family and friends to use it up and not just keep it on display!

Susie since starting to use ROE In liquid oils haven’t had any DOS on bar soap (touch wood). I’ve found some brand new oils from suppliers have been the culprits in the past - one was jojoba oil - well within the labelled date. It’s a cheap easy solution for me.
 
I tried using jojoba oil and a lot of other more expensive base oils, and my family preferred the higher lard soaps 100% of the time. And those were blind tests. All the same color, all the same shape, all the same scent. Just different recipes and labelled R13, P84, etc, so no clues in the naming. So, I stopped using expensive oils and short shelf life oils. That stopped my DOS. I am currently using 3 year old soap that is just fine.
 
my family preferred the higher lard soaps 100% of the time.
Ditto that! My family & friends favorite is my Hogwash Hair & Body Shampoo.
50/50 PKO/LARD. ;) After the first time he tried it, my (now 17 year old) grandson asked, "Can I have some more of that piggy soap?" 😂
 
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