Many seem to be using the sap given for “soybean, fully hydrogenated” successfully, but when I was first contemplating using GW 415 I found some posts on this forum where makers reported softer or stickier than expected soap. There has also been quite a bit of uncertainty expressed about the fatty acid composition of GW 415. In my quest to determine the “real” FA profile of GW 415, I tracked down the manufacturer’s product sheet and Certificate of Analysis documents on the CandleScience.com website,
here. Key information:
Fatty acid composition (typical values per 100 g):
- Saturated fat 44 g
- trans fat 39.4 g
- Monounsaturated fat 16.6 g
- Polyunsaturated fat 0 g
Iodine value: 45-55
So, what is the
trans fat??? Based on research papers linked in earlier soy wax threads and some I found on my own, it’s highly likely that the
trans fat is mostly elaidic acid, an unsaturated C18:1 fatty acid. If you don’t feel confident making that leap of faith, it’s easy enough to compare the iodine value range of 45-55 for GW 415 given by the manufacturer with the iodine values given for partially and fully hydrogenated soybean oil in the
soap calculators.
First, as given on the Soapy Stuff website,
here:
“The Iodine Number indicates the amount of of unsaturated fatty acids present. Soap made with mostly unsaturated (liquid) fats will tend to have a high Iodine Number and soap made with mostly saturated (solid) fats will have a low Iodine Number.”
The iodine number given in the SoapMakingFriend calculator for “soybean, fully hydrogenated” is
1 and for “soybean, 27.5% hydrogenated” is
78, both quite different from the
45-55 range for GW 415 given in the manufacturer’s COA sheets posted on the CandleScience.com website.
My research, calculations, reasons for settling on an NaOH sap of .144, estimated FA profile, and the results of some of my trial runs using various sap values are given in the thread I linked in post #6, above. I was more or less stumbling along at first, which probably makes it challenging to read the thread, but eventually my estimated numbers aligned well with the information available from the manufacturer.
And now for the easy part. I recently discovered that the SoapMakingFriend calculator allows a user to add a custom oil to the oil list. I used that feature to add “GW 415” with a KOH sap of .202, FA percentages I calculated and an average iodine value of 50 based on the range given by the manufacturer. SMFriend calculates the NaOH from a KOH sap. A KOH sap of .202 returns a NaOH sap of .144. The FA percentages I used are given in the linked thread.