A question about PH

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Moonday

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Hi
I have a receipt and try to better it! PH is 9.5 . When I check it in calculators I must have 6% super fat . But How this is possible? Why when I have super fat , I have 9.5 of PH ? I mean more PH is about Lye and it means I have super lye inside super fat in my soap? If it's true , why this twice supers never contact together?
How I can decrease PH less than 9 ?
Thank you for your respond
 
pH, as far as soaping is concerned, is pretty much a useless number. All lye-based soap will have a pH above 7 - you cannot have a low pH lye-based soap. It is also pretty hard to measure it accurately, so in all it is a distraction for soapers that seems important but has no bearing at all.

Your reading of 9.5 does not mean you have a lye-heavy soap - zap test your soap to find that out. No pH reading will tell you if your soap is safe or not. After all, what IS a safe reading for soap? There just isn't one figure at all, as various recipes can have various pH levels.

Put the pH measuring tools away, zap test your soap and carry on knowing it is all good.
 
It's my opinion that you're taking a few pH measurements far too seriously. First question -- why do you think the pH of soap should be lower than 9? I'm truly curious to know why you think this is true.

Some things to think about:

(1) pH readings of soap will vary quite a bit depending on how you do the measurement. You don't say if you're using a meter or test strips and you do not explain your method.

(2) pH readings within 0.5 units is (9 vs 9.5) are basically the same for the purposes of testing soap by a hobby soapmaker. We are not chemists in in a chemistry lab using standardized procedures that ensure high accuracy and precision.

(3) pH of SAFE soap varies from 9 to 11 and even higher. See the tables below. Dove "soap" in the pink table is NOT soap -- it is a synthetic detergent -- so ignore it in that table.

Dunn K Sci Soapmaking Table 13-1.jpg


Baranda soap irritation vs pH.jpg


Walton Feed soap pH.jpg
 
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My tests have shown 7.5-9.0 soap and all of them are mild. I don't even trust the accuracy of my test strips. I wouldnt worry about it if you are making bars of soap. If you are making shampoo, or pet soap then it's something to consider. I don't think you can lower the Ph of a cp bar of soap by much. You could make liquid soaps and lower the Ph.
 
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"... You could make liquid soaps and lower the Ph...."

Nope, that doesn't work. The normal pH range of potassium (liquid) soaps is roughly the same as for sodium (solid) soaps.

If you try to lower the pH of either type of soap by adding an acid, the soap instead starts to break down into fatty acids. In a bar soap, a lot of this decomposition is hidden because of its solid form. In a liquid soap (LS), you'll see the fatty acids separate out and float on the top of the remaining soap.

If you read the LS forums here and elsewhere, you'll eventually come across posts made by frustrated liquid soapers who are determined to lower the pH of their soap -- usually to the unrealistic "ideal" of 7.0 -- and then they complain that their soaps are doing weird things and separating and they wonder what they should do. The solution -- add alkali to re-saponify the fatty acids, which brings the pH back up to where it should be for the soap to remain soap. :Kitten Love:

It's the syndets (synthetic detergents) that have lower pH.
 
"... You could make liquid soaps and lower the Ph...."

Nope, that doesn't work. The normal pH range of potassium (liquid) soaps is roughly the same as for sodium (solid) soaps.

If you try to lower the pH of either type of soap by adding an acid, the soap instead starts to break down into fatty acids. In a bar soap, a lot of this decomposition is hidden because of its solid form. In a liquid soap (LS), you'll see the fatty acids separate out and float on the top of the remaining soap.

If you read the LS forums here and elsewhere, you'll eventually come across posts made by frustrated liquid soapers who are determined to lower the pH of their soap -- usually to the unrealistic "ideal" of 7.0 -- and then they complain that their soaps are doing weird things and separating and they wonder what they should do. The solution -- add alkali to re-saponify the fatty acids, which brings the pH back up to where it should be for the soap to remain soap. :Kitten Love:

It's the syndets (synthetic detergents) that have lower pH.

Good to know, I remember reading that was possible. I have never tried it.
 
Useful info and all great! Thank you all! I'm looking to start to sell my products and this is just with your great helps! Hope to success to us!
I was really worry about PH and test some Acids such as Citric but all of them decrease quality (Or may be I couldn't find a way to use of them :) ). Your info - my friends - relaxed me!
 
Yep, you shouldn't have said that...here is why...if you are asking questions like this, you are no where ready to sell soap. You need at least a year to develop good reliable recipes and make sure they are not going to develop DOS or any other bad qualities.

Lest you think that I am saying this because I don't want the competition for my business, I don't sell my soap. I only make it for my use, and friends and family use. It really does take about a year to get a good soap that you love, and you are sure it is not going to develop DOS.
 
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I think the original poster is being responsible with their time to find the proper and safest way to make soap before they start selling. With that in mind, it's also efficient use of their time to ask the "what if" questions while they wait years for their soaps to cure so they don't spend a horrendous amount of time, money, and effort just to ask those questions later and find out that running a business isn't for them. No one said they were going to start selling tomorrow. It sounds like many members here assume someone isn't going to wait the full year when they hear the word "sell".
 
I too was under the impression that Lye and Lard soap could be checked for PH to be sure it was fully cured and safe. I think I read it somewhere about making soap, but of course not everything we read is correct.
It was on the Interent so it has to be true, right. :crazy:

I bought some Phenolphthalein to test with which stays clear under PH 8.2 and turns pink to red between 8.2-12, a PH of 13 or greater also is clear but not much concern for error as pure lye is only either a 13 or 14 itself.
It was my understanding that Lye Soap should be under an 8.2 so my testing solution should stay clear.
However in testing Hot Process soap now I find some pink when using the solution.
Does that mean nothing all really? The soap cooked long enough Saphination should have been complete.

If testing for PH is not correct way to test the soap, then what is? Someone mentioned a ZAP test, what is ZAP? I did a search for ZAP TEST and word ZAP was ignored as too short or too common, and just TEST came up with about everything else.

I have 2 batches of Lye/Lard soap I want to test, one is cold process and 3 weeks old, and the other is hot process about 1 week old.

I know both should age awhile yet to make harder dryer bars, but for now I wanted to test for safeness and use some before making the next batches.



Thanks.
 
You are right in that pH testing isn't ideal. One thing that is not quite right is the usual pH of lye-based soap. Our soaps will always be in a range from 8 to 12 give or take a few points here or there. This does not mean that they are bad in any way.

You also were right about saponification being finished. The issue with soaps is what known as "excess alkali" which in essence means that there is unreacted lye in the soap (lye heavy) which is caused by a number of things. To test for this, we zap. This is my personal zap routine, which is similar to how many people do it -

1 - Wet your fingers and rub them on the soap to get a little bit of soapy water on your finger tips. If there is no tingling sensation............
2 - Touch a wet finger to the tip of your tongue. If there is no zap...............
3 - Touch the soap to the top of your tongue. If there is no zap, you are good to go.

Zap is really how it sounds - the tongue will feel like you have put a 9v battery on it and it'll will be a sharp sting. Be aware that some scents can cause a funny taste, of course, but you'll know zap when it happens.

The reason why I do this 3 stage is to help mitigate the concerns of people with sticking their tongue on an unknown soap. But you would have to keep the soap on your tongue for some time to cause a burn, which would be hard to do with it being to zappy.
 
Thank you!

I also just found the sticky (The Acronym and Abbreviation Definition Thread...)
that thread answers allot of my questions also that were not able to be searched for, like what was DOS I've read people having trouble with. Found the answer.

I guess soon as I am done with my coffee I'll go taste my soap! :thumbup:
Thanks for clearing that up about the unreacted lye in the soap I'm looking for, not the PH. I guess I was sort of looking for the right thing but in the wrong way.
 
Please don't laugh me but I started to sell my soaps :grin: I sell two or three Kilograms per week but I sell. I test my soaps at university and all of options was standard!!!
 

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