Hardening Soap

[pacmarrin]

I am new to this great hobby and am wondering if there is a preference between stearic acid and sodium lactate to make soap a bit harder? Thanks!

 

[Obsidian]

Sodium lactate or 1 tsp salt PPO is the most common hardening agents.

 

[seven]

i prefer sodium lactate. 1 tsp ppo. i've read that some used it up to 2% from the total oils, but i personally think it's too much.
stearic can be a bit tricky to work with, i rarely used it except for making mp base or facial soap. it is known to accelerate trace.

 

[DeeAnna]

Stearic acid, since it is a fatty acid, not a fat, will react instantly with lye and thicken the soap batter within seconds.

Like beeswax, stearic melts at a much higher temperature than regular soaping fats, so there is also the issue of getting it melted and mixed into the batter properly.

If you want a higher stearic content in a specialty soap, such as a shave soap, then added stearic may be necessary. But I'm with Seven -- I would avoid it for regular soaps.

That said, I prefer to formulate my soap recipes so they are hard enough to unmold easily without the use of additives.

 

[pacmarrin]

Thank you!

Thanks, all, for the helpful replies. Much appreciated and an early Happy New Year to each of you!

 

[Candybee]

I'm with DeeAnna on this. I prefer to tweak on my recipe to make my soap harder. Soapcalc can help you with this a lot.

Some of the oils I use to harden soap; cocoa butter, tallow, coconut oil, palm kernal oil. A little can go a long way.

 

[Relle]

I use SL at 2%, recommended from someone here and it works fine for me, been using it for a year now.