I am wondering how the cocoate ion (in natural soaps, in the form of sodium or potassium cocoate and from the saponification of coconut oil) differs structurally from the olivate ion (from the saponification of olive oil)?
My family is attempting to implement the methods in solveeczema.org and believe that our children have detergent-reactive eczema and our baby is most sensitive. In moving away from detergents and to natural soaps, we have started using soaps that result from the saponification of vegetable oils - mostly coconut oil, palm kernel oil, and olive oil. We discovered that our other child (a toddler) seems to react to these soaps in a similar way that he would react to a cleaner containing much stronger/harsher surfactants (such as sodium lauryl sulfate).
Our toddler seems to get bad eczema flares using soaps that contain cocoate, but he has no reaction to soaps that contain 100% olivate. I have no idea why this would be, since I would assume that both cocoate and olivate have the R-COO- structure. Is cocoate much more hydrophilic than olivate? Is the functional group different? Is the cocoate ion a longer molecule that looks much more like a harsh detergent than a salt resulting from saponification of olive oil or tallow?
Please note that this question is related to two questions already asked: