Lauric acid is considered to be non-toxic and safe to handle. Lauric acid vs. Lauric acid combined with glycerol will probably vary in their pH, but not so much so that Lauric acid can be viewed as corrosive and harmful. The glycerol probably buffers it a bit. Any pure form of an acid is going to be more acidic/corrosive than any buffered form. In the end, it may just be more of a marketing point. Undecenoic acid is buffered a bit by extra virgin olive oil, and more so in the calcium undecylenate form. It is the undecenoic acid form, however which tends to be more effective. in the pH mania world, acid is always worse, but that's not functionally so.