I manufacture a soft shaving soap from 100% KOH and is super fatted <10%
It has been toxicologist tested for the EU market and was given a 12 month shelve life.
Recently I had a customer who reported that his soap had separated just within the 12 month period. At first I thought it may of been bad storage conditions, heat damage.
But after asking him lots of questions I know believe that the soap became contaminated.
The soap intended use is to remove some of the soap product from it's container and with a wet brush, lather the soap in a separate shaving mug/bowl.
My customer was lathering straight from the products container. He then had a period of not using it and stored it in a cupboard with the lid on. After a couple of months he opens the tub to discover the separation. He also reported no bad smell. But this got me thinking, is it possible to contaminate the soap.
The soap formula has no preservative because it's expected PH level is 9.5-10.5 which inhibits growth. But am I right in thinking that adding tap water would reduce the PH level, introduce minerals for bacteria to thrive and if the brush is not clean introduce bacteria?
I have discontinued the shaving soap until I feel happy that the product is safe to use.
If contamination is the case then I need to make some obvious changes to this product.
Any help with this would be greatly received.