PH Testing/results question

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Cylistarr

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I made my first soap just over 6 week ago. I have Mackerey-Nagel PH test strips I purchased off Amazon that I have been using to test PH. I was of the understanding that the PH must be between 7 and 10. My soap consistently has shown at first 11, then 10.5 (test trip color not quite 11, and not quite 10).

Is the soap safe to use? How can it be so high still when it's sat and cured for over 6 weeks and I used a proven recipe to make it? Can it be the PH in the oils driving it up or could the lye have been a strong batch or something?

I had scale troubles (enough that I had to measure multiple times) but I did not relent until I achieved the correct weight of lye so I don't think that is it as both batches of soap I made are identical in their readings, and they are completely different in their ingredients.

I have tested some soap I have, made by the person I learned soapmaking from; that soap is a solid 10. (It is the exact same recipe I used for my first batch although the brands of oils were different.)

I'm about to just give up as this was a very expensive waste of money if I have to throw it all away. Very disappointed in the results because I was completely in love with making the soap.

Any help would be appreciated.

Thank you.
 
How did you test the pH? Did you just stick the strip onto a wet bar, or did you make a 1% solution of soap in distilled water and check that?

Mostly we do not worry about what pH our soaps are here. Some of the more chemically minded are doing some tests about using fatty acids to affect pH, you can search for those topics on the forum.

Your soap is probably fine. I would stop using test strips and/or phenolthaline. those things don't do anything to tell you if you have a lye excess anyway. Zap test it, and if it does not zap you, scrub up!
 
A pH between about 9 and about 11 is typical if the test is done correctly. The final pH will vary depending on the fatty acid content in the soap. Lye-based soap will not have a pH between 7-8.
 
Thank you for your replies and information. I have never heard of "zap testing" so I will go look that up. I don't know how to make "1% solution", so I will look that up also. To test it, I scraped a small amount of the soap off the bar and rubbed it around in the palm of my glove to make bubbles, then placed the PH strip in the bubbles and held it for a few seconds to make sure it was coated in the soapy water.

Edit: (A few minutes later.) OK, when I woke up this morning it never occurred to me that I would be sticking my tongue on a bar of soap... I'm chicken, so it may not have worked. I barely touched the tip of my tongue to the edge of the soap..I did not ..lick.. it. Is that..enough? I didn't feel anything but my tongue touching something.
 
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Also, pH strips are notoriously inaccurate when measuring the pH of salts. Soap is a salt created from the mixture of the alkali (NaOH), and the fatty acids (oils).

Zap testing is super easy, rub a wet finger on the soap, then touch that finger to your tongue. If you do not get the zapping sensation akin to sticking a charged 9 V battery to your tongue, then touch the tip of your tongue to it. If no ZAP, it's safe. Zap testing tests for free lye, not pH. pH does not matter in bar soap, unsafe soap does.
 
Susie is right -- testing the pH doesn't necessarily tell you whether the soap has excess lye or not. The problems with relying on pH are measuring it accurately and interpreting the result. A soap with pH 11 using one blend of fats might have no excess lye (aka no zap), but another soap with the same pH of 11 using another blend of fats might be lye heavy (aka "zappy"). So you have two soaps with pH 11, but one zaps and one doesn't. Which test is going to tell you more accurately whether the soap is safe enough to wash with -- the pH test or the zap test? For example, soaps high in oleic acid (olive oil) will have a "natural" pH about one unit higher than soaps high in lauric acid (coconut oil).

It's true that few soaps will have a pH higher than 12, but pH that high should be an unusual result, not a routine finding. If a soaper often makes soaps that are that alkaline, I'd look for something the soaper needs to fix with her recipe design or method of making soap. That said, even if a fresh soap has a bit of excess alkalinity, the soap isn't a failure (although I certainly wouldn't wash with it right away!). The excess lye (and thus the level of zappy-ness and the pH) will drop during cure, and the soap is likely to be just fine at the end of the cure time.
 
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Once again thank you so much for all the information, I did -very gingerly- touch the absolute tip of my tongue to the edge of my soap and felt nothing but just touching something. I have now done what Susie suggested and rubbed a wet finger on the soap and placed it on my tongue. It tasted terrible, but no "zap".

So this means I'm not a complete failure at making soap and I can actually make more. I was going to give up and just forget the whole thing. Thank you again for your help.
 
You're doing fine! And you are asking thoughtful questions that show you are going to do even better. Keep up the good work.

Oh ... and post pictures. It didn't really happen until you post pics! :)
 
Of course, I'm a little embarrassed since it's my first tries but I will post pictures just as soon as I figure out how. :)
 
Alright I posted pictures in the "Photos" section under "Cold Process Soap". I do hope that was the correct placement for those; if not, I apologize.

Please be kind..>.<;
 
I will try posting the URL from the image.. I simply clicked on the "Photos" tab; the one just to the right of the "Forum" tab. I posted the photos in the "Cold Process Soap" category. They're the two most recent submissions.



Thank you for your kind words, I can't take credit for the name, that was the name of the recipe I was given by the kind gentleman whose soapmaking class I attended. In an hour he told us so much, and even made soap right in front of our eyes, I was hooked.
 
You are doing it very well, please don't give up! Your soap sure looks better than my first. Congratulations!

All your questions are completely normal and we all started right where you are, you are in the perfect place to learn and can't wait to see your next batch.
 
That is some gorgeous soap there! You would not believe the homely mess I had for a first soap! And I had to rebatch it with additional oils because it was lye heavy. Yours looks like you've been doing this for a really long time!

Questions are actually a truly wonderful thing around here! For every person that asks the question, at least 5 other lurkers are reading it and getting good info. You keep those questions coming!
 
Thank y'all for your kind words. :) I really can't take credit though, as the kind older gentleman who taught the class I sat in made the soap right in front of us and gave me the first recipe. He was also incredibly generous and gave me one of his own hand-made wooden molds to get me started.

I do have a couple more questions since a few of you have mentioned asking them...hehe. (Warning, long and silly story ahead.)

So, this is probably a pretty ridiculous story, but here goes.. I'd watched tons of videos on youtube and after I made the first batch, I stubbornly decided I wanted to make soap that was round for my second batch. Couldn't afford a mold so I'd seen videos where they talked about a "Pretzel can" so I figured a Pringles can would work... I dragged my husband to the grocery store and made him pick out a kind he'd eat, and the next morning he proudly presented me with the empty can (gotta love that man). Well I figured I could make more soap so since I'd already done the Honey Amber one I decided to go to SoapCalc.net like the gentleman told us about and make a recipe using it so it'd be different. Famous last words..>.>

I apologize if this is getting long, but I am going somewhere with it. I lined the can with freezer paper like he'd taught us for the regular mold and Scotch taped it together. Naturally it didn't occur to me actually make a smaller batch, so I made the same size I did the first time, but it was too much to fit in the Pringles can. Not wanting to waste anything I used a cardboard toilet paper roll insert because I saw someone use something like that in a video, taped down to a piece of cardboard on the bottom and lined with freezer paper. Well, that, too, wasn't enough, so in desperation I grabbed the paper towel roll insert I'd just emptied and Scotch taped it to the toilet paper roll, lined it with more freezer paper and finished pouring the almost mashed potatoes consistency soap into it. (Just wait, it gets better.)

So 24 hours later I went to unmold this fantastic round soap and found that the soap had seeped through the freezer paper and had a reaction with the (possibly aluminum) silver spray coating on the inside of the Pringles can. Where it touched the can the soap looked like it had gotten super-heated, and had a strange shape, all wide wrinkles. I threw away what had seeped out and was touching the can itself, but what stayed inside the freezer paper I saved, even though it has an odd odd shape.

My question, now that I've explained my crazy story, is this: is the soap safe to use? Also (side note: I used some really expensive Wintergreen oil that I had laying around but it did NOT smell good with the soap in my opinion, it also turned it much whiter than it was, is this normal?)

(My apologies for the long post, I'll try to keep it shorter next time.)
 
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