If you are a Melt and Pour Soaper you will probably have seen this happen to your soap at some point.
Hmm, well, apparently men sweat, and ladies perspire - or is it glow?? Anyway, until the last couple of years, this frosted, beaded look that would appear on Melt and Pour Soap, and very occasionally Cold Process Soap was known as "sweat". I see it now referred to as "dew", which of course makes it much more delicate sounding! Either way, quite frankly, it's a bit of a pain, and something we wish would never happen!
Why does it happen? Two things are needed - a humectant (which in soap is glycerine, both in Melt and Pour and Cold Process Soap) and a moist atmosphere (as in rainy weather or humidity). It is not the way of Cold Process Soap to sweat, however this can occur during wet winters, or for instance, if you have set up at a craft fair ventue the night before and it's chilly and damp in the morning, and your Cold Process may look moist. In the Farmer's Market or Craft Fair situation, use an old doona over your tables to help insulate overnight - it works a treat.
Anyway, back to Melt and Pour Soap and sweating - the moisture is being pulled towards thte soap, it's not the soap exuding the moisture. Glycerine, and other humectants draw moisture towards them, which is why we use them in skin care. On your soap, this materialises in beads of slightly greasy feeling beads of 'sweat', 'dew' or whatever you would like to call it!
Prevention - is way better than cure!
- Don't overheat your soap when you are melting it.
- Avoid moisture loss during heating, cover the jug or pop the lid on the crock pot.
- Allow your soap to sit in an air tight, dry environment for the first few days after manufacture.
- Wrap your Melt and Pour Soap - it's best to use shrink film, or bags, or cello, or store at home in an airtight display jar.
- If you forget or your soap does sweat, it is fine to use, just wipe away with paper towel, or blunt knife.
So, it's just a cosmetic effect, your soap is fine to use, and will be moisturising, but it doesn't look appealing, so avoid it if you can!