Phenolphthalein

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Angezzz

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I tested 8 of my soaps today with Phenolphthalein. I put a couple shreds of each soap in warm water in a small plastic cup and mixed them up. I tested each with a pH test strip and they all showed around 8. I added the Phenolphthalein to each cup and instantly they all went pink. After a few minutes three of them stayed pink and the other 5 went purple and one went orange (that soap was orange coloured) I am not sure what is safe and what is not safe. I would think the three that are very pink are lye heavy (those were my castile soaps) I am not sure about the others that still have a pink tinge. The 5 that are pink/purple are about a week out of the mold. The three castile soaps are months old...
 

shunt2011

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PH strips do nothing for testing your soap. Soap is going to have a high PH period. 8-10.5 some higher. You need to zap test your soap. Scroll to the bottom here and you will find more posts on the subject. If your soap doesn't zap your soap is fine and dandy to use. If doing CP wait about 24-48 hours to test. If HP you can test after the cook. :)
 

The Efficacious Gentleman

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I would zap test them. pH tests don't test for unreacted lye and it is possible to have a safe test with a higher pH than one with unreacted lye.

Soaps will always be alkaline and one of the most important things is the recipe for deciding what is good or not for the skin. Not to mention the issues with actually getting an accurate reading. Hence the zap test. Some people say it isn't safe, but this is how I and others here do it, which greatly reduces what minimal risk there is -

1- wer your finger and rub it on the soap. Wait for a tingle

2- if it doesn't tingle, touch the soapy finger to the tip of your tongue gently. If it is okay

3- touch the soap itself to the top of your tongue. If it still doesn't zap, you're okay.

Zap is like putting a 9v battery on your tongue, if you ever did that. I have been zapped many times and sometimes harshly - soaps with KOH really hit hard - and my tongue has not fallen out yet [emoji106]
 
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