the common consencious is that the sap value on the most lye calculators is too high.
I'm actually one of those that doesn't buy into the low coconut sap. When I first stared soaping 2 years ago there were quite a few discussions about this topic on a couple of the soaping forums that I frequent, and being a new soaper at the time, I was quite confused about the whole 'coconut sap controversy', and so I started my own thread on one of the forums and asked about it because I wanted to get to the bottom of it . In the end of those discussions on that forum, the majority consensus was just the opposite- that the 'low sap' theory was a wash (no pun intended :wink: ).
What decided the issue for me was a chemist on that particular board who gave her input. According to her chemistry reference books, .136 sap for coconut is awfully low especially when compared to the Merk Index she had on hand (a standard lab reference book), which gives the sap range for coconut oil to be between .180 - .188. From what I understand, there is not a singular sap number that's
the sap number for a particular oil. In the chemical books, SAP numbers are always listed as a range because of the different methods the oil was extracted and the quality of the oil, etc.... , but .136 is drastically below the accepted range. I personally use the SoapCalc's .183, which is on the low end the the Merk Index's range. It's a good, approximate, 'within the range' SAP.
I figured out that if I used a .136 sap for coconut instead of .183 for my 20% superfatted coconut bars, they would in reality be superfatted at 40%. I've always wondered if that is why some of the people making the 20% superfatted coconut oil bars kept complaining of getting oil slicks on top of their soaps. At .183 I've never had an oil slick with my 20% superfatted coconut oil soap.
A lot of people get confused about the whole 'coconut sap' thing because coconut oil in lotions is quite moisturizing, yet drying in soap, so they conclude that the SAP must somehow be wrong. But what I've gleaned in my soaping journey is that the very cleansing, high lauric acid content saponified coconut oil is a much different animal than the very moisturizing, unsaponified kind.
Things totally change when saponified with lye. Coconut oil really does need a lot of lye to
completely saponify it because of it's particular fatty acid profile. When one lowers the sap, all one is really doing is superfatting it. That's why it feels better on one's skin. It's not that the sap is too high, it's just that the normally moisturizing quality of unsaponified lauric acid chemically transforms into a very efficient cleansing machine when mixed with lye and not many skins can handle their body oils being stripped away.
when you think about it that is why everyone seems to luv the salt bars so much, not drying and ubber lather . the higher superfat used for these is essentially the same thing as lowering the sap value.
Exatcly!
