Ph Testing Cosmetics Products - A Few Tips

Every time I try a new formula, tweak an existing formula, or replace even a single ingredient with something from a different supplier, I will whip out my PH test strips and do a quick test of the product.

I go through quite a few of these, and will sometimes use 2 different ones – partly to see if they bring the same result, and partly to try the occasional different brand. Although pH strips are not as accurate as a pH meter, they will give an initial indication.

Pictured above: a batch of multi-vitamin cream is being tested. This cream has a generous dose of carrot extract, giving it a rich yellow color. The thickness of the product combined with its color makes it a bit tricky to get an accurate reading.

Drip – Don't Dip!

Testing a liquid product is as easy as dripping a few drops of the product onto a strip and waiting for the color to change. This can take anywhere from a nanosecond to 30 seconds, depending on what you are testing.

I cannot recommend dipping a test strip into your freshly-made product. An inferior strip (they happen) or tape will bleed color into the product. I have on more than one occasion had to start all over due to an inferior PH testing product.

Gently Gently

Testing the PH of cream or lotion is a little different. The strip needs to have product applied to it, then sit for a bit (sometimes up to 5 minutes) before it registers. To read the strip, blot the strip very carefully until the product is removed. I've done everything from completely stripping off the little squares to smearing color all over because I wasn't gentle enough when removing the cream/lotion.


Trying Something New

Here is a new PH strip I am trying out at the moment. This one is a bit more annoying to use than my 'old faves' because the squares don't line up with the printed guideline. Also, the guideline is not an accurate enough rendition of the actual colors, so it's hard to match up. On the positive side, these strips do have a large range, going all the way up to PH 14 (more than I'll ever need).


The Old Faves

These are my favorite test strips and I have used them for years. As you can see, they are both accurate and easy to read. One could ask why the heck I try other brands if I am happy with these. Truth: they're pretty pricey, and I will fall for special offers as easily as the next person – even on lab equipment and PH test strips!

PS: A couple of requests about PH test strips prompted this post. I hope this has been helpful to you who asked, and not too nerdy for you who didn't.

Comments

Rikke said…
Not to nerdy to me. Thansk for sharing :-)

Kh Rikke
Lise M Andersen said…
Thanks Rikke,
I go through all kinds of trial and error with so many things (ingredients, equipment, production methods) - it's just a never ending learning process. It's really a joy to be able to share my experiences with people who are interested!
Katie said…
Could you tell me what brand you're using that's more accurate? And where can I find one? Thanks!
Lise M Andersen said…
Hi Katie - It's a German brand called Macherey Nagel that make my favorites. I order them from a lab equipment supplier here in Denmark. Are you in DK?
Katie said…
Hi, Lise. I'm in the US. I was able to find something similar here after searching around for a long time. Thanks!!
Lise M Andersen said…
I hope it works out for you Katie!
Anonymous said…
Hey- what is the U.S. brand that you found? Thanks :)
Katie said…
I got it here: http://www.lotioncrafter.com/ph-fix-indicator-strips.html
Lise M Andersen said…
Thanks for sharing the info Katie!
Anonymous said…
Thanks..Everyone!!!
Anonymous said…
Great post! What is the name of your "old fav" pH strips?
Lise M Andersen said…
Hey there Anon - These are made by a company called Macherey-Nagel. Find them here http://www.mn-net.com/