It really depends on your preference. Some people like colloidal oatmeal, which is very very fine. I like a bit of scrub to mine. For a fine grind, you can use a spice mill or coffee mill if you have one.
Periodically I like to clean out the coffee grinder by grinding something like rice to absorb the oils from the coffee beans. So using the coffee grinder for oatmeal seems to just follow pretty well.
But I also have a spice mill and it makes for a finer grind than the coffee bean grinder, so that's what I have used more recently when I wanted 'colloidal' oatmeal to add to soap.
Baby oatmeal sounds like a really good idea, but no babies here.
"Colloidal" oatmeal is precooked to extract the beta glucans and gelate the starches so they burst. Then it's dried and ground super-fine. The beta glucans in low doses like a bath give the silky feel, progress up to "slimy" as concentration increases, and end at "glue-y" like a cold porridge. A fine grind without the precook, will still begin releasing the glucans when poured into hot water, but precooking makes it instant. The old-fashioned or instant oatmeals that most of us tend to have in the cupboard were also steamed and rolled, so they're sort of half way there even if you don't explicitly cook them.
If I wanted to use colloidal oats in a soap, I'd do something similar to what brewers call a "decoction." Grind them up really fine, then cook them in some reserved quality of your soaping water, let the whole mess cool then add it wet.
I use Bob's Old Red Mill Oat Flour at a rate of 1 tsp to 1 Tbls PPO for a nice creamy texture. Not only do you not have to grind it up, but it also has the advantage of washing cleanly down the drain, leaving no particles behind to clean up.
I don't have babies in the house anymore, but I use baby oatmeal because I hate scratchies in my soap (was never able to grind my rolled oats fine enough to my liking). Using oat flour like Zany recommended, though, sounds like a great idea. I may have to try that in my next oatmeal soap.
StephanieLeong said:
May I ask if you just add oatmeal to your recipe or do you need to adjust the ingredients?