Not so! You've done a great job science-ing on this one!
Homemade Vanilla Stabilizer?
- Thread starter AliOop
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Don't apologize for your abilities as a scientist -- you're doing far better than most, Todd. Very few people have the patience to do the methodical testing and evaluation you're doing.
It's also normal procedure to have others review one's calculations. I have to confess when I was in grad school, my major professor corrected my math a few times -- as you can see, I don't always get it right. So you don't need to apologize for that either.
It's also normal procedure to have others review one's calculations. I have to confess when I was in grad school, my major professor corrected my math a few times -- as you can see, I don't always get it right. So you don't need to apologize for that either.
I did a little web hopping this morning with the goal of learning more about the use of sodium thiosulphate and sodium metabisulfite in cosmetics, especially in terms of safe usage rates. Apologies in advance if information here duplicates anything posted above.
First off, an Aussie soap making supplier has posted results after 5 months for MP soap made with homemade vanilla stabilizer (thiosulphate), here:
https://www.baysidesoap.com.au/2020/02/06/diy-vanilla-colour-stabiliser/
I found a brief discussion of use of thiosulphate and sodium metabisulfite for lotion at this link: sodium thiosulphate....looking to reduce browning (oxidation) with Vanillin — Cosmetic Science Talk
where a poster, Ozgirl, contributed this on why sodium thiosulfate can be listed as fragrance:
“The loophole is probably to do with the IFRA Transparency List.
IFRA Transparency List
IFRA describes two types of ingredients used in fragrances - Fragrance ingredients and Functional ingredients.
Functional ingredients are substances that are not used to provide odor or malodor coverage, but which are essential for the functionality or durability of a fragrance compound – such as an antioxidant, preservative, diluent, solvent or color.
Sodium thiosulfate is listed as being used in fragrances as a functional ingredient so if it is added to your fragrance to stop oxidation you can probably get away with listing the combination (fragrance + sodium thiosulfate) as "fragrance".”
That led me to the IFRA website where I found an August 2019 document from the Cosmetic Ingredient Review Expert Panel (CIR) titled “Safety Assessment of Sulfites as Used in Cosmetics.” I skipped to the end of the long document and on page 52, the conclusion stated is:“The CIR concluded that Sodium Sulfite, Potassium Sulfite, Ammonium Sulfite, Sodium Bisulfite, Ammonium Bisulfite, Sodium Metabisulfite, and Potassium Metabisulfite are safe as used in cosmetic formulations.”
I haven’t been able to find a similar document that specifically discusses sodium thiosulfate/thiosulphate, but found this 2014 CIR document:
https://www.cir-safety.org/sites/default/files/inorganic sulfates.pdf
which on page 92, states “... the CIR expert panel concludes Sodium Sulphate to be safe as used in rinse-off formulations, and safe up to 1% in leave-on formulation.”
also, this:
https://www.ewg.org/skindeep/ingredients/706203-SODIUM_THIOSULFATE-SODIUM_THIOSULFATE/
As for getting to a standardized formula, the pentahydrate version of thiosulfate, which I’ve read is more shelf stable, has 5 attached water molecules compared with the anhydrous form. I think that means more of it is required to get equivalent concentrations of thiosulfate in a solution compared with using the anhydrous form.
First off, an Aussie soap making supplier has posted results after 5 months for MP soap made with homemade vanilla stabilizer (thiosulphate), here:
https://www.baysidesoap.com.au/2020/02/06/diy-vanilla-colour-stabiliser/
I found a brief discussion of use of thiosulphate and sodium metabisulfite for lotion at this link: sodium thiosulphate....looking to reduce browning (oxidation) with Vanillin — Cosmetic Science Talk
where a poster, Ozgirl, contributed this on why sodium thiosulfate can be listed as fragrance:
“The loophole is probably to do with the IFRA Transparency List.
IFRA Transparency List
IFRA describes two types of ingredients used in fragrances - Fragrance ingredients and Functional ingredients.
Functional ingredients are substances that are not used to provide odor or malodor coverage, but which are essential for the functionality or durability of a fragrance compound – such as an antioxidant, preservative, diluent, solvent or color.
Sodium thiosulfate is listed as being used in fragrances as a functional ingredient so if it is added to your fragrance to stop oxidation you can probably get away with listing the combination (fragrance + sodium thiosulfate) as "fragrance".”
That led me to the IFRA website where I found an August 2019 document from the Cosmetic Ingredient Review Expert Panel (CIR) titled “Safety Assessment of Sulfites as Used in Cosmetics.” I skipped to the end of the long document and on page 52, the conclusion stated is:“The CIR concluded that Sodium Sulfite, Potassium Sulfite, Ammonium Sulfite, Sodium Bisulfite, Ammonium Bisulfite, Sodium Metabisulfite, and Potassium Metabisulfite are safe as used in cosmetic formulations.”
I haven’t been able to find a similar document that specifically discusses sodium thiosulfate/thiosulphate, but found this 2014 CIR document:
https://www.cir-safety.org/sites/default/files/inorganic sulfates.pdf
which on page 92, states “... the CIR expert panel concludes Sodium Sulphate to be safe as used in rinse-off formulations, and safe up to 1% in leave-on formulation.”
also, this:
https://www.ewg.org/skindeep/ingredients/706203-SODIUM_THIOSULFATE-SODIUM_THIOSULFATE/
As for getting to a standardized formula, the pentahydrate version of thiosulfate, which I’ve read is more shelf stable, has 5 attached water molecules compared with the anhydrous form. I think that means more of it is required to get equivalent concentrations of thiosulfate in a solution compared with using the anhydrous form.
Todd Ziegler
Circle Z soaps
Thanks for the hard work. You can also find usage safety from the FDA for metabisulfate and thiosulfate because they are both used in the food and medical industry. I know that metabisulfate is approved for internal consumption but in no way am I recommending that. It is used as a preservative for wine.
Zany_in_CO
Saponifier
This relates to using anhydrous sodium thiosulphate vs, the less expensive sodium thiosulphate pentahydrate form.
From the web:
Molecular weight of sodium thiosulfate is 158.11
Molecular weight of sodium thiosulfate pentahydrate is 248.19
Molecular weight of 5 water molecules is 5x18 = 90 (which nicely accounts for the weight difference between the two forms)
The less expensive, pentahydrate form of thiosulfate is 63.7% sodium thiosulfate by weight and the rest is water. I think that means 1.57x by weight of the pentahydrate form would be required to get the same concentration in solution for a given weight of the anhydrous form (sodium thiosulfate).
From the web:
Molecular weight of sodium thiosulfate is 158.11
Molecular weight of sodium thiosulfate pentahydrate is 248.19
Molecular weight of 5 water molecules is 5x18 = 90 (which nicely accounts for the weight difference between the two forms)
The less expensive, pentahydrate form of thiosulfate is 63.7% sodium thiosulfate by weight and the rest is water. I think that means 1.57x by weight of the pentahydrate form would be required to get the same concentration in solution for a given weight of the anhydrous form (sodium thiosulfate).
Todd Ziegler
Circle Z soaps
I think I understand what you mean. You are comparing the two forms of thiosulfate and how much to use for the same effecisy rate. Am I close?
I will need to go back to find your numbers. I was looking at a 5lb bag of the pentahydrate form on Amazon for 16.99 including shipping. By the calculations I did above, it would yield to 3.2 lbs of sodium thiosulfate, which then works out to $5.30/lb. The cheapest anhydrous form I’m finding is about $19.00/lb with shipping.
Todd Ziegler
Circle Z soaps
I bought mine from ebay and it was $11 for a pound.
And I also saw where someone had earlier posted 3 pounds of anhydrous on Amazon for around $15 with free shipping. Looks like the cost could be as low as $5-$5.50/lb if the pentahydrate form works works as well as the anhydrous form, or that low priced anhydrous is legit. I imagine that making chemicals anhydrous and ensuring purity adds cost.
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For CP soap, I don't think I'd start with just the thiosulfate. The results from the original article in post #1, as well as @glendam's experiment/video (also posted way back in this thread) were done with thiosulfate. While they did lessen the discoloration, they did not eliminate it.
In contrast, Todd's experiments with the mix of the two resulted in complete elimination of the browning (to date), even with high vanillin fragrances. And he has stated his belief that it's probably the metabisulfite that's doing the work for CP soap, whereas the thiosulfate is probably for M&P soap. His instincts and research have been great so far.
If I were going to start with just one of the two, my money would be on the metabisulfite. Ebay lists it as low as $6.25/lb with free shipping. Amazon has it as low as $4.42/lb with free shipping for Prime members. But the reality is that Todd will probably finish his experiments and report his results, long before I finish up the bottles that I bought right as this thread started.
Todd, we should all be chipping in to send you a Christmas ______ (honey-baked ham, case of beer, bottle of fine wine, box of Neuhaus chocolates, fill-in-your-choice-of-treats-here).
In contrast, Todd's experiments with the mix of the two resulted in complete elimination of the browning (to date), even with high vanillin fragrances. And he has stated his belief that it's probably the metabisulfite that's doing the work for CP soap, whereas the thiosulfate is probably for M&P soap. His instincts and research have been great so far.
If I were going to start with just one of the two, my money would be on the metabisulfite. Ebay lists it as low as $6.25/lb with free shipping. Amazon has it as low as $4.42/lb with free shipping for Prime members. But the reality is that Todd will probably finish his experiments and report his results, long before I finish up the bottles that I bought right as this thread started.
Todd, we should all be chipping in to send you a Christmas ______ (honey-baked ham, case of beer, bottle of fine wine, box of Neuhaus chocolates, fill-in-your-choice-of-treats-here).
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Oh, good distinction on the MP versus CP soap factor. I only read through the entire thread once and I’m sure I missed a lot of important details. Do the manufacturers make the mix of thiosulphate and metabisulfite so they have all bases covered for MP, CP, lotions, etc?
WSP has three different VCS products, one for M&P, one for CP and one for lotions. I took a quick look and didn’t see anything listed about the ingredients, so it would take someone more knowledgeable than me to uncover what might be in them. I also have read that their version doesn’t work very well, but I can’t remember where. Seems to me I’ve read it several times though.
I've also read that WSP's version doesn't work well. Back when I was on FB, many soapers were saying how the stabilizer only worked for a certain amount of time, and then the browning was inevitable at some point during the cure.
My guess is that the VCS works differently in different soap recipes. With endless combinations of oils, micas, fragrances, and other additives, it's not a simple task to come up with something that will work for everyone.
My guess is that the VCS works differently in different soap recipes. With endless combinations of oils, micas, fragrances, and other additives, it's not a simple task to come up with something that will work for everyone.
Thank you for sharing so generously.Very interesting will chk
Todd Ziegler
Circle Z soaps
The patent that I read included a lot of testing of different combinations of metabisulfate and thiosulfate in differing amounts. It even included different chemicals in conjunction with metabisulfate but the final winner in the tests was the recipe that I shared.For CP soap, I don't think I'd start with just the thiosulfate. The results from the original article in post #1, as well as @glendam's experiment/video (also posted way back in this thread) were done with thiosulfate. While they did lessen the discoloration, they did not eliminate it.
In contrast, Todd's experiments with the mix of the two resulted in complete elimination of the browning (to date), even with high vanillin fragrances. And he has stated his belief that it's probably the metabisulfite that's doing the work for CP soap, whereas the thiosulfate is probably for M&P soap. His instincts and research have been great so far.
If I were going to start with just one of the two, my money would be on the metabisulfite. Ebay lists it as low as $6.25/lb with free shipping. Amazon has it as low as $4.42/lb with free shipping for Prime members. But the reality is that Todd will probably finish his experiments and report his results, long before I finish up the bottles that I bought right as this thread started.
Todd, we should all be chipping in to send you a Christmas ______ (honey-baked ham, case of beer, bottle of fine wine, box of Neuhaus chocolates, fill-in-your-choice-of-treats-here).
My tests are mirroring the same results that were achieved in the very thorough patent testing process.
I do wish someone who is using the VCS from WSP would chime in because I would like to know what there's smells like but if I am not mistaken, someone did find the percentages used in the crafters choice VCS.
I don't need a gift, just send me pictures of your soap with the ZCS results.
I didn’t realize that vanillin would discolor lotions! I thought it was the lye or the saponification process that causing the browning reaction (the Maillard reaction of the soaping world, lol). This is good to know, thank you!
I gave lotion making a try - it’s not for me. But I have bought and scented a premade base for years and it will discolor. Maybe not as readily or as dark as CP, but that might be due to a lower usage rate. M&P will discolor as well and in that case the lye and oils have already saponified.
@TheGecko this is the soap I experimented with, in which it seems the ROE is helping, which I added to the oils before adding the lye solution. The fragrance is chocolate mint from Nurture soap (discontinued).
I put thiosulfate in a 1:1 rate to half of the soap and poured it in the mold. The other half I did not add thiosulfate and expected it to get dark brown. I attempted a drop swirl with it, without realizing that in a tall and skinny mold it was likely to look like deformed buttocks.
it has been 3 weeks and the top half has yet to discolor the way it did the first time I used the fragrance, which is linked below.
How this fragrance did last year, after 2 weeks:
Chocolate mint
I put thiosulfate in a 1:1 rate to half of the soap and poured it in the mold. The other half I did not add thiosulfate and expected it to get dark brown. I attempted a drop swirl with it, without realizing that in a tall and skinny mold it was likely to look like deformed buttocks.
it has been 3 weeks and the top half has yet to discolor the way it did the first time I used the fragrance, which is linked below.
How this fragrance did last year, after 2 weeks:
Chocolate mint
Todd Ziegler
Circle Z soaps
I really don't need a gift and I appreciate the thought. If you really want to get something, then give me the gift of calling it ZCS, I really think that it deserves a spot in the abbreviations permathread and we can all take credit for it.For CP soap, I don't think I'd start with just the thiosulfate. The results from the original article in post #1, as well as @glendam's experiment/video (also posted way back in this thread) were done with thiosulfate. While they did lessen the discoloration, they did not eliminate it.
In contrast, Todd's experiments with the mix of the two resulted in complete elimination of the browning (to date), even with high vanillin fragrances. And he has stated his belief that it's probably the metabisulfite that's doing the work for CP soap, whereas the thiosulfate is probably for M&P soap. His instincts and research have been great so far.
If I were going to start with just one of the two, my money would be on the metabisulfite. Ebay lists it as low as $6.25/lb with free shipping. Amazon has it as low as $4.42/lb with free shipping for Prime members. But the reality is that Todd will probably finish his experiments and report his results, long before I finish up the bottles that I bought right as this thread started.
Todd, we should all be chipping in to send you a Christmas ______ (honey-baked ham, case of beer, bottle of fine wine, box of Neuhaus chocolates, fill-in-your-choice-of-treats-here).
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