What exactly is the difference you experience when you add lard or tallow as opposed to palm oil or palm kernel oil?
In addition to being able to claim the soap is 'all vegetable' to those who care, some soap makers claim animal fats 'have been shown to clog pores.'
I like the idea of using 100% vegetable oils, even making 100% olive oil, in part so I can more easily distinguish my soap from commercial products when people ask; but if tallow or lard makes a better soap, even as a small percentage of the ingredients, then I want to experiment with it. I've used lard, about 20%, and couldn't see a difference, but there were other variables.
So what, specifically, are the benefits of tallow and lard, and what percentage would you add to an olive oil based soap?
I certainly like the idea of using a cheaper fat, but when I go to the trouple of making soap, cost is a secondary consideration. Speaking of cheap, what differences would I see substituting soy or canola oil for olive?