What keeps out soap with addatives from rotting?

[boyago]

What keeps our soap with addatives from rotting?

Anybody got an explanation for what keeps our rot prone additives from rotting out our soaps? I don't really get nervous for the more innocuous additives that I could see rotting like oatmeal or the oils themselves. But I always a little astounded when my yogurt or buttermilk soaps don't go south. Then I see people throwing in fruit like bananas or avocado and I just can't not think they will rot. I figured it had something to do with the PH crash of the lye sterilizing the batter but allot of this stuff we seem to HP or throw in at trace to try avoid the lye reacting with the stuff we're putting in. Seems like a dash of Vit E or ROE shouldn't fight off all that action.

 

[savonierre]

I use fresh avocado, carrots and cucumber. I do not know why they don't rot, but know they last for years. I gel my soap so maybe the high temperature helps?

 

[Neve]

I would assume it's due to a lack of oxygen within the soap... maybe the PH is a factor too. The additives are surrounded by fatty acids. Just nothing in there that can react with the fresh stuff is my guess.

I believe there is a chemist or two on this forum? They might know.

 

[new12soap]

It's the high pH. Anything really well blended and in small amounts is pretty safe, anything with chunks will get moldy and disgusting really fast.