Inspired by a thread started by @Orla here, I've recently been comparing 2 soaps that have very similar recipes and fatty acid profiles, with the big exception that one is made with cocoa butter and the other with shea butter.
The main difference between cocoa en shea butter is that the first has more palmitic acid, while the latter contains more stearic acid. My cocoa butter soap had 15% palmitic and 11% stearic acid, while my shea butter equivalent contained 8% palmitic and 18% stearic acid. Cocoa butter also has a bit less oleic acid than shea butter, so the cocoa butter soap had some extra (refined) olive oil added to the recipe to make up for that difference (the % of oleic acid was the same in both recipes). There was a slight difference in linoleic+linolenic acids, with the cocoa butter soap having a pinch more of those (10% total vs 8% in the shea butter soap). Lauric+myristic was kept the same in both recipes.
What I notice is that the cocoa butter soap lathers a bit easier and produces a slightly creamier/silkier lather. The enourmous amount of tiny bubbles between my hands make it feel like my hands aren't really touching when I rub them together (which they do slightly with the shea butter soap). The shea butter soap on the other hand, seems to produce fewer, but (slightly) bigger bubbles. The difference is pretty small, yet clearly noticable. The first time I noticed a difference, I was using a bar made with unrefined cocoa butter and I thought the unsaponifiables might play a role, but when I switched to another bar that was made with refined cocoa butter , the difference was still there. I very much prefer the scent I used in the shea butter soap, but I keep grabbing the cocoa butter soap for its luxurious feel.
There are a few other differences between the soaps that might play a role, so I want to point those out.
First of all, the cocoa butter soap is shaped differently, it's a flat rectangular ("regular soap") shape, while the shea butter soap is a more square-ish box shape - this means the rubbing surface of the cocoa butter soap is bigger and might therefore contribute to easier lathering. This is only true for the refined cocoa butter soap though, the initial unrefined cocoa butter soap was also more box shaped.
Second, the cocoa butter soaps were both made in October 2019, while the shea butter soaps were made in February 2021, they're 18 months and 14 months old respectively. I think with a decent cure those 4 months shouldn't make a big difference, but it might still play a small role.
Lastly, I think there might be a chance the 2% difference in linoleic+linolenic acids might play a role in lather. I've heard it can sometimes increase lather, though I don't feel I have enough experience with differences in linoleic+linolenic acid in soap to be able to distinguish a higher from a lower L+L soap. The 2% difference is smaller than the 7% difference in palmitic vs stearic acids, so I assume are that the palmitic vs stearic content of the soap played a bigger role that the L+L content.
I'm not sure if there's something inherently amazing about cocoa butter or if the balance between palmitic and stearic acids is just better, but I seem to clearly favor my cocoa butter soap over the shea butter version that is very similar in many aspects.
The main difference between cocoa en shea butter is that the first has more palmitic acid, while the latter contains more stearic acid. My cocoa butter soap had 15% palmitic and 11% stearic acid, while my shea butter equivalent contained 8% palmitic and 18% stearic acid. Cocoa butter also has a bit less oleic acid than shea butter, so the cocoa butter soap had some extra (refined) olive oil added to the recipe to make up for that difference (the % of oleic acid was the same in both recipes). There was a slight difference in linoleic+linolenic acids, with the cocoa butter soap having a pinch more of those (10% total vs 8% in the shea butter soap). Lauric+myristic was kept the same in both recipes.
What I notice is that the cocoa butter soap lathers a bit easier and produces a slightly creamier/silkier lather. The enourmous amount of tiny bubbles between my hands make it feel like my hands aren't really touching when I rub them together (which they do slightly with the shea butter soap). The shea butter soap on the other hand, seems to produce fewer, but (slightly) bigger bubbles. The difference is pretty small, yet clearly noticable. The first time I noticed a difference, I was using a bar made with unrefined cocoa butter and I thought the unsaponifiables might play a role, but when I switched to another bar that was made with refined cocoa butter , the difference was still there. I very much prefer the scent I used in the shea butter soap, but I keep grabbing the cocoa butter soap for its luxurious feel.
There are a few other differences between the soaps that might play a role, so I want to point those out.
First of all, the cocoa butter soap is shaped differently, it's a flat rectangular ("regular soap") shape, while the shea butter soap is a more square-ish box shape - this means the rubbing surface of the cocoa butter soap is bigger and might therefore contribute to easier lathering. This is only true for the refined cocoa butter soap though, the initial unrefined cocoa butter soap was also more box shaped.
Second, the cocoa butter soaps were both made in October 2019, while the shea butter soaps were made in February 2021, they're 18 months and 14 months old respectively. I think with a decent cure those 4 months shouldn't make a big difference, but it might still play a small role.
Lastly, I think there might be a chance the 2% difference in linoleic+linolenic acids might play a role in lather. I've heard it can sometimes increase lather, though I don't feel I have enough experience with differences in linoleic+linolenic acid in soap to be able to distinguish a higher from a lower L+L soap. The 2% difference is smaller than the 7% difference in palmitic vs stearic acids, so I assume are that the palmitic vs stearic content of the soap played a bigger role that the L+L content.
I'm not sure if there's something inherently amazing about cocoa butter or if the balance between palmitic and stearic acids is just better, but I seem to clearly favor my cocoa butter soap over the shea butter version that is very similar in many aspects.