After several weeks of waiting to see how the melt & pours soaps would react to various vanillin percentages, the final results are in. Quite honestly, the soaps look pretty much the same as they did 11 days ago when I did my first testing review. As you can see in the above picture, the non-darkening vanilla had poor results. (L) is the non-darkening vanilla fragrance in clear soap base. It was was originally colored in our Neon Bright Blue liquid gel color. At this point the color has become completely "opaque" and darkened to an almost navy color. (R) soap was a white base that was scented and colored the same. It, too, has darkened and the color has changed substantially.
The picture below really tells the story of how much the color has changed. Soap on the (R) is the original color. As you can see, there is a major color difference several weeks later. At this point, I am fairly certain that we will be discontinuing the Non-Darkening Vanilla fragrance oil. You will understand this decision even more when you see how the Vanilla fragrance oil compares in the test results. Also, the longer the Non-Darkening Vanilla soaps sat on the shelf, I began to note a slight"off" smell to the scent.
Pictured below are the test results of the vanilla fragrance oil in both white and clear soap base. It scored well in my opinion. There were no brown spots and only a slight change from the original blue color (the clear base seemed to darken slightly more). The fragrance held well.
The soaps with vanilla fragrance and mixed with vanilla stabilizer were uncolored (below). As you can see the white soap base has turned a light eggshell color. The clear soap base has remained fairly transparent. I gave this a thumbs up and believe the vanilla stabilizer does help prevent brown spots and color change is minimal.
The biggest surprise for me was how well our Peppermint Fragrance tested. It has a 10% vanillin content and the soaps and the blue colors never changed. Peppermint scent remained stable as well. The Butt Naked (with a 5/8% vanillin content) did have a very slight color change. I found that odd since it had a lower vanillin content than the peppermint fragrance.
Bottom line is you need to test your soap base with your fragrance selection every time. Keep a soaping diary on what works and what doesn't. Taking pictures of your test results is also helpful. Once our new GPE soap bases are in stock (should be very soon!), I will be testing them as well to see how they fair with many of our fragrance oils and especially those with higher vanillin content. The raw ingredients in soap bases can also affect how well certain fragrance oils perform. Again, this is why you will want to keep accurate records and test in small batches.