Friday, October 10, 2014

Friday Wonderings: Can we substitute one water soluble ester for another in a deodorant? Why do I have less volume than I expected?

In this post on making deodorants, Alaska asks:  I looked up Herbarie and was wondering if the AquaEm or Cromollient SCE would work in place of the water soluble esters? Thanks! 

In the original recipe, I'm suggesting cyclomethicone - an oil soluble silicone - or Crodomol PMP - a water soluble ester. So yes, we can substitute one water soluble ester for another.

First, check the INCI name of the ingredient you've found at the Herbarie. I don't think it's proper name is AquaEm. If we look, its INCI is PEG-6 Caprylic/Capric Glycerides (and) Polyglyceryl 6 Dioleate, an ester with a proper name of Caprol Micro Express. (Okay, it's mostly Caprol Micro Express or CME. Close enough for our purposes!)

Can you use Cromollient SCE or Caprol Micro Express as a water soluble emollient in this recipe? Yes, you can. Is it a good idea? Yes, because both bring a lovely emolliency to the product. CME isn't a sticky feeling ingredient, so that's a great addition to a deodorant. And Cromollient SCE is a mildness enhancer, which is a great addition as well.

So the final answer to your question is yes, you could substitute either of those water soluble esters for the original water soluble ester.

In this post, How do I modify a recipe when I add or substract something? madux asks: I have trouble getting specific amount in my shampoo recipe, i wanted to get 250 ml but ended with about 220 ml of shampoo. I wonder if that is because of the powdered ingredients... Could you explain to me why that happened and how to fix it?

This is due to the density of your ingredients. Density is measured by is the idea that 1 gram of water is 1 ml. This makes it easy to figure out how much water you have when you have 1 gram or how much 1 ml of water will weigh. Here's the thing, though. Not everything is 1 ml = 1 gram. For instance, glycerin is heavier than water, while oils and essential oils are lighter.

If we have 100 grams of water, it will measure 100 ml. If we have 90 grams of oil, it might measure 100 ml. If we have 80 to 90 grams of essential oils, they might measure 100 ml. If we have 100 grams of glycerin, it'll be less than 100 ml. Every ingredient has a different weight to volume ratio. So it's easy to see that volume and weight don't measure up together.

This is, as I've mentioned many times before, we don't use volume measurements because using 5 ml of something like glycerin isn't the same as using 5 grams of glycerin. If we do everything by weighted measurements, we know we're actually getting 5% of something and 10% of something else. The original commenter didn't do this, 

In your recipe, you have glycerin and cocamidopropyl betaine and a lot of other ingredients that are quite thick, meaning that 1 gram of that ingredient isn't going to measure out to 1 ml. Because of this, you'll have a lower volume than you expected.

*Thanks, p, for the catch! I always get this backwards!!!

Related posts:
How do I figure out the volume of a recipe?
Weight vs. volume

9 comments:

p said...

Hi Swift! I think you have it backwards: 90 g of oil might measure 100 ml, and 80 g of essential oil might measure 100 ml.

Susan Barclay-Nichols said...

Argh! I get that wrong every time! And I think you correct me every time! Thanks!

I'll correct it when I'm at my computer in the morning!

Susie Flores said...

I'm still shopping around for sodium stearate. Does anyone have a supplier for this? thanks!

Susie Flores said...

Finally found the stearic acid at www.ingredientstodiefor.com I missed it the first time!

Susan Barclay-Nichols said...

Hi Susie. Stearic acid isn't the same as sodium stearate.

Sânziene şi Mătrăgună said...

regarding the volume / weight expected vs actual:

1. take into account the product remaining on our beaker's sides and on tools / spatulas
2. take into account that heat and hold DOES mean that water will evaporate. Weigh your containers before heating and compensate for the water. OR add 10% extra water before the heat and hold phase.

Susie Flores said...

Shoot! I knew that and I still mixed them up. Thanks, so much. I probably wouldn't have realized it was too late!!

lynn said...

If we have 100 grams of water, it will measure 100 ml. If we have 90 grams of oil, it might measure 100 ml. If we have 80 to 90 grams of essential oils, they might measure 100 ml. If we have 100 grams of glycerin, it'll be less than 100 ml. Every ingredient has a different weight to volume ratio. So it's easy to see that volume and weight don't measure up together.

If glycerin weighs more than water, wouldn't 100 grams of glycerin weigh more than 100ml, since 100 grams of water = 100 ml and glycerin is heavier? or am I confused?

Susan Barclay-Nichols said...

Hi Lynn. 100 grams of glycerin will weigh 100 grams, but it will have a volume of less than 100 ml because it's heavier than water.

100 ml of water weighs 100 grams. 100 ml of glycerin should weigh 125.9 grams.

Yes, 100 ml of glycerin would weigh more than 100 ml of water. But 100 grams of glycerin is the same weight as 100 grams of water.