PH Level

[Dean]

I'm adding an ingredient with a PH of about 8 at %5 to an overall solution that has a PH of about 5. Will the additive significantly increase the PH of the product?

Additive:
5%
PH = 8

Solution:
95%
PH = 5

 

[psfred]

Maybe, maybe not. Depends on the buffering capacity of the two solutions and what they are.

 

[Dean]

Maybe, maybe not. Depends on the buffering capacity of the two solutions and what they are.

Thanks fred. Here's the entire recipe;

Additive: 5% Sodium Lactate (60% sol)

Other:
5% Olivem 1000
5% Willow Bark Extract
85% Orange Blossom Water

 

[DeeAnna]

What Psfred said. There's no way to know for sure even knowing the ingredients. I'd guess the olivem will do some buffering, but it's hard to say. A person could spend quite a bit of time estimating this and when it's all said and done, all you'd have is an estimate.

Honestly, the easiest and best way to find out is to get a pH meter calibrated and test the mixture. I know that's not what you want to hear, and you may not be in a position to measure the pH accurately, but that's the only surefire way to learn the answer.

 

[Clarice]

@DeeAnna do you have experience with pH meters that would lead you to recommend one over another?

Thank yoU!

 

[DeeAnna]

Nope, I don't have a recommendation. I don't own a pH meter because I'm not willing to invest the money required to get a truly good one and I'm also not willing to do the ongoing maintenance required to keep a pH meter in tip-top shape. I don't think a lot of people realize no matter how much or little you use a pH meter, you still have to maintain it regularly to keep the sensor functioning properly. So it's not something I'm going to own unless I have a need to test pH regularly and I want to get accurate numbers.

If I needed to know the approximate pH of stuff I make, I would probably get Machery-Nagel (M-N) pH strips or other very high quality pH strips in as narrow a pH range as will work for what I want to do. In other words, I would never get strips that read from 0 to 14 pH and think I was going to get any kind of accurate reading. If I wanted to know soap pH, I'd get the M-N strips for 7-14 pH and accept that the results are probably not going to be highly accurate even in a properly diluted soap solution. I'm going to look for trends, not accurate numbers. If I wanted to adjust my lotion pH to be somewhat under pH 7.0, I'd probably get the M-N 5.1-7.2 strips.

More on the care and feeding of pH meters:
http://www.just4growers.com/stream/...niques/how-to-take-care-of-your-ph-meter.aspx
https://hannainst.com/ph-electrode-maintenance-calibration-guide
https://www.epa.gov/sites/production/files/2018-01/documents/eq-01-08.pdf
https://blog.nhbs.com/wildlife_equipment/ph-meter-calibration-maintenance/

 

[Clarice]

@DeeAnna, thank you so much.

I am looking for something that would tell me if lotions I am making are within the range with which the preservative works.

Thanks much for your insight on a getting strips with a narrow range - makes 100% sense to me!

This might sound nuts (probably is) but is there a reference that would provide the pH of oils / butters / additives used for lotions? Perhaps it is simple as reading the MDS more carefully? Thank you!

 

[DeeAnna]

You will never find a list of pH for oils or butters. By definition, things that don't have water in them, including oils and butters, do not have a pH. A product must have water in it to have a pH value.

Additives may or may not have listed pH values -- you'll have to look each one up. The pH can vary depending on how the pH is measured, so you'll have to pay attention to the method used for measurement.

For soap or synthetic detergents, the accepted method for measuring pH is to dilute the soap or syndet to a 1% or 10% solution on a pure basis. The numbers may be slightly different whether you use 1% or 10%. And the pH is definitely going to vary a lot if you try to measure the pH of a more concentrated solution of soap due to the way soap interacts with water.

Another thing about pH is that it isn't additive, although I get the impression that many people think it is. You can't mix something with a pH of 4 with another something that has a pH of 8 and absolutely end up with a pH of 6. It might work out that way, but it's even more likely to be something quite different.

 

[Clarice]

Thank you @DeeAnna I learned something new today!

 

[Cellador]

I splurged recently and got the pH meter available through Lotioncrafter. I am starting to make some syndet products that utilize some high pH surfactants that need to be adjusted....I believe the pH for leave-on products is supposed to be around 4.5-5.5. For hair, a little higher (maybe 5.5-6.5).

 

[DeeAnna]

Just to be clear -- I'm not saying a pH meter isn't worth having and using ... just that I personally would not use it enough to make it worthwhile for me to own and maintain a meter. This is very much a "your mileage may vary" kind of thing.

 

[SoaperForLife]

I splurged recently and got the pH meter available through Lotioncrafter. I am starting to make some syndet products that utilize some high pH surfactants that need to be adjusted....I believe the pH for leave-on products is supposed to be around 4.5-5.5. For hair, a little higher (maybe 5.5-6.5)

I have the same meter. I believe that SCM has some good info on pH meters on her blog for people like us.

 

[Clarice]

@SoaperForLife - who is SCM? Thank you!

 

[Cellador]

SCM is Swift Crafty Monkey. Susan Barklay Nichols. She used to have a free blog with tons of info on making B&B products, but now it's by subscription only. You can join for as little as $1 per month.
I have the $10/month subscription and it is so worth it!
Ok, my fan-girling is over....