Additives during dilution?

[Lyma]

Hi there,

I keep on reading that it's really important not to adding any food additives during dilution due to bacteria growth.
1. I'm just wondering what's the real difference for adding e.g. strawberry juice at the beginning of the process than adding it during dilution? The fruit juice will be there in the final soap, one way or another. It's not that it reacts with the lye, just like oils, so it would transform into something else. It will still remain as a juice in the final product.

2. Also, adding water infusion with herbs or flowers during dilution, is less prone for bacteria than adding fruit juices or milks?

Thank you in advance

 

[DeeAnna]

1. I'm just wondering what's the real difference for adding e.g. strawberry juice at the beginning of the process than adding it during dilution? The fruit juice will be there in the final soap, one way or another. It's not that it reacts with the lye, just like oils, so it would transform into something else. It will still remain as a juice in the final product...

Nope, it's not just juice anymore because the lye definitely does react with components of the juice. Think about it. The color of the juice often changes -- that's caused by a chemical reaction with lye. The soap heats up more with fruit juice than without -- that's the simple sugars reacting with the lye. Test it -- mix some juice with NaOH solution and see what happens. Check for a temperature rise and color change.

"...2. Also, adding water infusion with herbs or flowers during dilution, is less prone for bacteria than adding fruit juices or milks?..."

I'm not sure I agree with that. Infusions and hydrosols can and do support microbial growth. Just leave a cup of an infusion or hydrosol and a cup of plain water on your desk for a few days and see which one grows interesting stuff.

 

[IrishLass]

Ditto what DeeAnna said^^^.


IrishLass

 

[Lyma]

Nope, it's not just juice anymore because the lye definitely does react with components of the juice. Think about it. The color of the juice often changes -- that's caused by a chemical reaction with lye. The soap heats up more with fruit juice than without -- that's the simple sugars reacting with the lye. Test it -- mix some juice with NaOH solution and see what happens. Check for a temperature rise and color change.

"...2. Also, adding water infusion with herbs or flowers during dilution, is less prone for bacteria than adding fruit juices or milks?..."

I'm not sure I agree with that. Infusions and hydrosols can and do support microbial growth. Just leave a cup of an infusion or hydrosol and a cup of plain water on your desk for a few days and see which one grows interesting stuff.

Yes you have a good point on both.
Just trying always finding ways to protect better natural ingredients during the process, but sometimes you get the opposite result, such as a moldy or oxidized soap.
Thank you very much