I'm as curious as a cat. This weekend I made a very small loaf of a mostly palmitic soap, another with equal palm and stearic, and then one of mostly stearic. (Surely somebody has already done this?) A pinch of different color mica was mixed into each loaf so I wouldn't get them mixed up. In a few weeks there should be some clue as to the differences. I am already sure there will be differences because they behaved differently when making them. We know stearic is less soluble than palm, but does it matter much? Is it worth sacrificing longevity for a really bubbly bar? What is a happy medium? What is the bell curve like? Is there a lot of latitude? I love bubbles but need more longevity.I don't know whether a 50:50 mix of palmitic and stearic acids is significantly different in soap ...
P=palmitic, S= stearic
The pink soap on the left is P 25%, S 5% = 30%
The blue in the middle is P 15%, S 15% = 30%
The green on the right is P 6%, S 24% =30%
All the other fatty acids in the three soaps were almost identical. I can put the recipes in if anyone wants to see them. I know the pink and green soaps are extremes, but it is just for this test.
(Wish I hadn't bothered with the dried rose bud on the pink soap.) I don't use palm so I bought 8oz of palm oil at Hobby Lobby just for this experiment. Compared to my usual soap it was nice to deal with and traced slower than I am used to, which I appreciated. The equal parts soap was also nice but traced a bit faster. The mostly stearic was a pain to deal with. I narrowly avoided soap on a stick! It was stop and plop. No stick blending needed.
Fortunately, I knew that was coming and was ready for it thanks to previous wisdom from @ResolvableOwl. I had to use some free stearic acid to get the numbers up and that instantly saponifies. But I had to do that for the sake of the experiment. This morning it doesn't want to come out of the milk carton. I will try to release it tomorrow. By the way, the blue and the green soaps are vegan and palm free.
Another question: I didn't make a swirled soap, so am I not mixing well or is the mica sinking down? I think the swirls are pretty but not what I expected. I know there is ash on top.