pH of LS

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bodhi

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Wondering what are your usual pH levels for LS? I have read everywhere that 9-10 is generally what you end up with. Im having a hard time understanding this as the mine always end up in the 7 range. Anyone else getting in this range?
 
How are you testing? My guess is that the strips you are using are inaccurate or the device needs calibration. If your ls legitimately had a ph of 7 it would not be soap. I believe the lowest ph possible is 8.5 and lower that that you have fatty acids and water. Can I ask why you are testing at all?
 
Soap is an alkaline product and will not have a neutral pH. Lower your pH too much and it starts to break apart as Meganmischke has said. The lower the pH, the less cleansing ability too. If your testing device is telling you your Liquid soap has a pH of 7, it is most likely not very accurate as true liquid soap (not enhanced with a chemical detergent) will not have a pH that low.
 
Im testing with a meter that is calibrated and they are indeed soaps that are not separated and contain no chemical detergents. I was surprised by the readings too so i changed the batteries and re calibrated. same readings. I was testing because i sell and i think its a good practice.
 
How exactly are you using the meter to test your soap? And has the meter been stored and maintained properly? I don't own a meter myself, but I've read that if they are not stored and maintained properly that they can give you false readings. Also, they can become contaminated by fats and proteins, and interference from other charged ions can mess with the pH readings. I've also read that the probes on a meter need to replaced every 1 or 2 years at minimum. Based on how sensitive they are to all of those things, and based on what I know about lye-based soap (liquid or solid), I have a good hunch that the pH meter is giving you false readings.

IrishLass :)
 
I am going to have to echo the others. If your reading is 7 in unseparated liquid soap, then something somewhere is wrong. It is either the meter or the process.
 
Thanks for the input everyone. The meter is accurate and the soap is soap. Im not sure what could be 'wrong' with the process. IrishLass, Im immersing the tip in the soap and it has been stored and maintained properly. Just to clarify again, the readings are not 7. They are in the 7 range.

I appreciate all your input, but I'm still wondering if anyone can share the pH levels your getting in your LS?
 
My soaps' pH typically range between 8.8 - 9.8 depending on the formulation. I do not add any neutralizing additives either as I don't formulate with a lye excess and feel I get the best stability this way. Higher coconut oil soaps tend to come out with a slightly lower pH, higher olive oils soaps tend have a bit higher pH. Whenever my soaps go below 8.5 by use of citric acid, they slowly start to cloud then separate and develop a thick layer of fatty acids at the surface.
 
I just measured the pH on all my liquid soaps that I currently have on hand. They range from 100% CO dish soap to 100% lard soaps, shampoo, and shower gel. The pH ranges from 8.9-10.7. All of them were made using no lye excess and neutralization.

I then added a citric acid solution to bring the pH of the 8.9 and the 10.7(separately)down to 8.0. In both jars, I have clear liquid on the bottom with a thick white layer on the top.

I just maybe lack the science education to understand how you could have liquid soap "in the 7 range" without something else added that I am completely unfamiliar with. Would you be so kind as to share your recipe/process so maybe I can learn from you? I would really appreciate it!
 
I was testing because i sell and i think its a good practice.

Why?

I'm not being sarcastic, I just don't understand the need to try to test pH in soaps. It is notoriously difficult to get an accurate reading, and even if you do get one, what difference does it make? A soap with a pH of 9 can feel too harsh and a soap with a pH of 10.5 can be very gentle and mild. So what does pH actually tell you? As near as I can tell it won't even tell you if it's lye heavy.

:confused:
 
Thank you FGOriold and Susie. Im going to look through my notes and see if there is something i did that i dont recall. Ill post back with updates....
 
Why?

I'm not being sarcastic, I just don't understand the need to try to test pH in soaps. It is notoriously difficult to get an accurate reading, and even if you do get one, what difference does it make?

:confused:

I test because I find it rather easy to do so. I would rather take a couple seconds to check than be notified after the fact that someone has used it and there was a problem with it.

The difference is that if i find a reading that is unexpected, I can figure out why... before a customer has a bad experience.
 
Why?

I'm not being sarcastic, I just don't understand the need to try to test pH in soaps. It is notoriously difficult to get an accurate reading, and even if you do get one, what difference does it make? A soap with a pH of 9 can feel too harsh and a soap with a pH of 10.5 can be very gentle and mild. So what does pH actually tell you? As near as I can tell it won't even tell you if it's lye heavy.

:confused:

Knowing the pH of your liquid soap is important for troubleshooting problems one may be having with it - especially if pH adjusters or buffers are added to account for a lye excess in a formula. Many people formulate with a lye excess that is then neutralized after dilution - this neutralization can and will alter the soaps pH and if problems arise, knowing the pH is an important tool.
 
Why?

I'm not being sarcastic, I just don't understand the need to try to test pH in soaps. It is notoriously difficult to get an accurate reading, and even if you do get one, what difference does it make? A soap with a pH of 9 can feel too harsh and a soap with a pH of 10.5 can be very gentle and mild. So what does pH actually tell you? As near as I can tell it won't even tell you if it's lye heavy.

:confused:

Well, in this case, it was a good thing that she did check her pH. I, personally, would not trust a liquid soap with a pH of 7 not to do funky things later. So, no selling or giving away until I was sure it was not going to separate or spoil.
 

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